Re: [Repeater-Builder] A DB224E antenna...
Our club bought a new DB-224E a couple of years ago for around $650 and it has been a great performer. We oriented the top and bottom dipoles to the north where we needed the most gain and the two center dipoles to the south where our primary coverage is required. Our site is on a ridge overlooking the village to the south where most of our users are located. We replaced an ancient DB-224 which had been modified with 2 inch extensions on the top and bottom of each dipole to move it down into the ham band. The harness was in sad shape on the old one and was probably the reason we saw the remarkable improvement in coverage on the new antenna. Also the original antenna had one dipole on the north side and three on the south side of the pole. Our antenna extends above the top of a 30 ft wood pole barely above the trees. Our primary route into the area is in a canyon where this antenna performs with a lot of multipath and this problem was solved with a linked repeater with a figure 8 directional antenna sited alongside and oriented to cover the canyon. A home brew colinear array with 4 half wave elements was used for this antenna (a lazy H stood up on end). http://sbarcnm.org/gallery_code/Camelot-Rptr018.html 73 - Jim W5ZIT --- On Thu, 9/2/10, Ray Brown kb0...@sbcglobal.net wrote: From: Ray Brown kb0...@sbcglobal.net Subject: [Repeater-Builder] A DB224E antenna... To: Repeater-Builder@yahoogroups.com Date: Thursday, September 2, 2010, 8:26 PM Greetings. I'm the trustee of our local club's 2m repeater. It's NE of the big town of Joplin, MO. (147.210) What I want to find out, I'm going to ask our club to buy a new 224e antenna (assuming that this is the correct version needed for T147.210 R147.810), and arrange the elements on the north edge of the tower we're on so that 3 elements point to the SW, to favor our town so that HTs can work it, and one element to the ENE to point some energy to Springfield for working severe weather. Altho I'm thinking about trying to link the repeater with either EchoLink or some other repeater to Springfield and just point all 4 elements to the SW. :-) But it's on the north leg (that leg points to the north), so if pointing them to the SW gets the highest gain, that sounds great to me. :-) The point is that there's a DB224 there now, not sure if it's an E version or not, but I think it has some issues right now, so I'd rather just get a new one up and bring the old one down and go thru it at our leisure, plus reorienting it so that we can actually USE it. :-) Anyways, I wanted to know if anyone had one here that was in either new- in-box or barely used condition, how much $$ they go for nowadays, and how hard is it to reorient the elements if it was originally designed / set for omni (3, 6, 9, 12 o'clock). Thanks! Ray, KB0STN Trustee, W0IN
Re: [Repeater-Builder] Which Antenna Analyzer?
The MFJ analyzers have very limited use around an RF active site. Any RF picked up by the antenna being checked will interfere with the readings on the analyzer. I even had problems recently trying to check the SWR on a horizontal loop antenna for HF, when a high power AM broadcasting station about 5 miles away was on the air. RF picked up by the loop prevented the analyzer from reading the SWR. The only reliable way I know is a Bird 43 and a transmitter to check the SWR. Even then you have to avoid using the low power slugs as the RF picked up by the antenna from nearby transmitters will cause an error in checking the performance of the antenna under test. 73 - Jim W5ZIT --- On Sun, 1/31/10, John Transue jtran...@cox.net wrote: From: John Transue jtran...@cox.net Subject: [Repeater-Builder] Which Antenna Analyzer? To: Repeater-Builder@yahoogroups.com Date: Sunday, January 31, 2010, 10:26 AM I would like to have an antenna analyzer. The most common with hams seems to be the MFJ analyzers, but I am not a fan of MFJ. So, what do you all use? I'd like the analyzer to cover HF through ham UHF. It would be nice to have it tell me the sign of the reactance, but I guess this can be easily inferred by varying the frequency around the resonance. Thanks in advance for your views and experience. John
Re: [Repeater-Builder] Duplexer vs Split Level Antennas
Allan, my mobile radio was a GE Progress line - either 30 or 60 Watts. I had both and don't remember which I used most of the time. The antenna at 1000 ft was connected to some kind of commercial solid state converter (which I don't recall) and 1000 ft of RG-58 (at 10 meters) carried the signal down the tower. The repeater was an elaborate system with the 146.34/94 as the main machine. There was at least one other open repeater on 146.16/76 which was for use in the Ft Worth area only. The transmitting antenna was on the west side of the tower and it was pretty much shielded from the east toward Dallas. Unfortunately, the receive antenna at 1000 ft prevented coordination of another 16/76 repeater for 150 miles to the east. At 90 miles we asked for 16/76 but were assigned the 'odd' frequency of 19/79. I think there were other 'private' repeaters as part of the system using CTCSS access. The trustee was Harold Reisor W5SXK and he had the hub for the system at his QTH. I never got to see any of the gear, but heard about it in bits and pieces over several years. As I understood it, each receiver connected to the 10 meter down converter was connected to a 420 transmitter linking to Harold's house. There he cross connected to a 420 link back to the transmitter site for each of the transmit frequencies. Interestingly enough, he also had a 94 receiver linked to his house, and one evening when we had some extended propagation, he linked the 94 receiver to the 94 transmitter. The Little Rock Arkansas 34/94 repeater was loud and clear on the 94 receiver in Ft Worth and although there was a honk each time a local station on the Ft Worth 94 repeater let up, as soon as another station keyed down on 34 he was repeated on 94 with no problem. This just illustrates how much isolation the 34/94 system in Ft Worth gained with the 500 ft separation on the receive and transmit antennas. The signal on 94 from Little Rock was that much stronger than the local transmitter on 94. As I understood it, the 34/94 repeater in Little Rock also had the capability (by the control op) of listening on 94 and retransmitting on 94 and several QSOs were had between stations in the coverage of the Ft Worth repeater with stations on the Little Rock repeater, with the two repeaters linked on 94. This is a recollection from back in the early '70s' in the last century so hope I have remembered it right. It was the most robust repeater we had in the area till they put up the big towers at Cedar Hill and a few repeaters gained access to antennas at 1500 ft. 73 - Jim W5ZIT --- On Fri, 1/29/10, allan crites wa9...@arrl.net wrote: From: allan crites wa9...@arrl.net Subject: Re: [Repeater-Builder] Duplexer vs Split Level Antennas To: Repeater-Builder@yahoogroups.com Date: Friday, January 29, 2010, 5:13 AM Jim That's a very interesting posting of the repeater(s) you were aware of and worked reliably from some 90 miles away in Texas. Perhaps you could provide us some of the parameters of the installation, like the receive antenna used at the 1000' level, the type converter used to convert the received signals to 10 M , the transmit antenna (any one will do) at 500', the coax used to connect it to the transmitter, and the PO of the transmitter. I'm not sure I understood you correctly about the coax downlead you indicated was connected to the receive antenna, was it RG-58 from the top of the tower to the receivers below or some other type coax? Also what was the PO of the GE mobile you were using? Thanks Allan Crites WA9ZZU
Re: [Repeater-Builder] Alinco DR-135 and RLC-4
I have used a pair of DR radios in a cross band repeater and all the signals you will need are present on the DB9 connector. Use the 1200 Baud packet connections and you will be all set. Realize that the COS output is an open collector that keys to ground, so you will have to use a pull up resistor to interface the RLC-4. The radios are configured so that if you wanted, you can directly connect the COS to the PTT of the other radio and connect the audio out to the audio in of the other radio and they will repeat. 73 - Jim W5ZIT --- On Sat, 1/30/10, ve6cpu satk...@inetdesign.org wrote: From: ve6cpu satk...@inetdesign.org Subject: [Repeater-Builder] Alinco DR-135 and RLC-4 To: Repeater-Builder@yahoogroups.com Date: Saturday, January 30, 2010, 12:10 AM Just a warning up front. I'm really new to the RLC-4. I've done 1200bps packet on a bunch of different radios. I've got my hands on a RLC-4 that I'm thinking of hooking up to a pair of dr-135 radios. Looking at the docs on the both the controller and the radio it seems I could use the 9 pin din on the back of the alinco to run audio and COS to and from the controller. Just wondering if anyone out there has tried this before? Is this something that can be done easily or do I have to get in to the radio and pull the audio and COS from somewhere else? I don't want to hurt either piece of equipment just trying things out. Thanks for any help you can provide. Stephen VE6CPU
Re: [Repeater-Builder] Duplexer vs Split Level Antennas
One of the best working repeaters I have run across was located on the outskirts of Ft Worth Texas on a 1000 ft tower. It used a single receive antenna at 1000 ft into a down converter that output on 10 meters. Several 10 meter receivers were connected to the RG-58 downlead in the radio room at the bottom of the tower. Each transmitter used a separate antenna at 500 ft and it was one of the best coverage repeaters for the flatlands that I have seen. I could reliably work it from 90 miles away with my mobile GE Prog. Vertical split antennas can work very well indeed. 73 - Jim W5ZIT --- On Thu, 1/28/10, wb0goa aero...@gmail.com wrote: From: wb0goa aero...@gmail.com Subject: [Repeater-Builder] Duplexer vs Split Level Antennas To: Repeater-Builder@yahoogroups.com Date: Thursday, January 28, 2010, 1:49 PM Have chance to install a DB 224 at 450' and another one anywhere below it. Using LDF6 on both runs. RF solid state 110 watts out. Wanting to know the pros or cons of running both antenna close together for more height with duplexer or spacing antennas for isolation without duplexer?
Re: [Repeater-Builder] Celwave/Sinclair, etc. antenna conversion to 2-Meters?
I have converted quite a few DB-224 antennas that were originally used in the 155 mHz range down to the 146 mHz range by adding a folded aluminum tubing stub to the top and bottom of each element. Using the folded tubing from a defunct TV antenna I flatten about 3 inches on one end and then wrap it around the top and bottom loops of the antenna. A hole drilled through the flattened metal allows a screw and nut to be used to clamp the stub to the element. There is no dissimulator metal problem with this aluminum to aluminum connection. After installation I cut the length of the stub to 2 inches. This has brought every antenna I have modified down to the 146 center frequency without having to modify the harness. SWR is not perfect without the harness mod, but is sure a lot less trouble. These antennas are perfectly usable with no modification at all in the ham band, but an improvement in the SWR can be had with this simple mod. This mod has been discussed on this forum several times. 73 - Jim W5ZIT --- On Fri, 1/15/10, larryjspamme...@teleport.com lar...@teleport.com wrote: From: larryjspamme...@teleport.com lar...@teleport.com Subject: [Repeater-Builder] Celwave/Sinclair, etc. antenna conversion to 2-Meters? To: Repeater-Builder@yahoogroups.com Date: Friday, January 15, 2010, 9:40 PM Several years ago, I found an article on the internet about converting the typical 150-174 MHz folded-dipole VHF antennas to 2-Meters. The article had each folded dipole element electrically lengthened by drilling a hole at the bottom and the top of each aluminum tubing element, and mounting a small bolt and nut - thus lengthening the overall electrical length of the element and lowering the resonant frequency. Possibly the coax harness was also rebuilt. The article I'm thinking of had nice color pictures and was a very well done web page article. I haven't been able to find this article, using Google and using the terms that I thought would be a good match. Does anyone remember this article and know what the url might be? These antennas often pop up surplus for cheap (often free), and they're very stout. I see in the catalogs that some versions are rated at 120 MPH wind velocity, and have a 6-year warranty! I've just been given one, too, and it appears to be almost brand-new. It would be a shame to just send it to the metal recyclers when I know there have been good conversion articles. Thanks and 73, Larry
RE: [Repeater-Builder] FS: *NEW* UHF Motorola Micor repeater on Ham band
Nah - we used GE. 73 - Jim W5ZIT --- On Sat, 1/9/10, Jeff DePolo j...@broadsci.com wrote: From: Jeff DePolo j...@broadsci.com Subject: RE: [Repeater-Builder] FS: *NEW* UHF Motorola Micor repeater on Ham band To: Repeater-Builder@yahoogroups.com Date: Saturday, January 9, 2010, 8:07 AM Maybe there's a whole stash of ham-band Micors sitting in a government warehouse somewhere. Maybe Area 51? --- Jeff WN3A _,___
Re: [Repeater-Builder] Was Repeater Battery Question
We use two 6 Volt Golf Cart batteries in series bought from Sams Wholesale to power a GE Mastr II repeater and GE Mastr II mobile link radio with the amp disconnected. The audio amp has been disabled on both radios. The angle on the solar panels was optimized for the winter months. Our panels deliver a total of 6 amps in bright sumertime sun. 73 - Jim W5ZIT --- On Fri, 1/8/10, rrath rr...@charter.net wrote: From: rrath rr...@charter.net Subject: [Repeater-Builder] Was Repeater Battery Question To: Repeater-Builder@yahoogroups.com Date: Friday, January 8, 2010, 11:02 PM Well, I did not receive any replies to my question. So I will ask this question: For those of you that have solar operated repeater sites, what type of battery are you using? Are you satisfied with them? Thank you. Rod kc7vqr
Re: [Repeater-Builder] Mastr II mods and parts
I leave my IDA controller intact, just put the repeat switch in the inhibit position. All necessary connections can be made to the repeater for an external controller on the two Molex connectors on the upper left side of the rear of the chassis. I use the unused frequency select pins to bring out the rest of the connections needed to the system board. Jumpers from the freq select pins where they extend through the system board connect to the audio and COS pins on the receiver board that extend through the system board. I use the old style sockets from miniature tube sockets to push over the pins extending through the system board. Mic and PTT terminals already exist on the Molex connectors. If the external controller fails, just unplug it from the Molex connectors and move the repeat switch on the IDA controller back into the repeat position for emergency operation. 73 - Jim W5ZIT --- On Tue, 1/5/10, Joe k1ike_m...@snet.net wrote: From: Joe k1ike_m...@snet.net Subject: Re: [Repeater-Builder] Mastr II mods and parts To: Repeater-Builder@yahoogroups.com Date: Tuesday, January 5, 2010, 8:22 AM You can make the IDA controller MASTRII work for you, but you aren't going to find a drop-in controller. Look at: http://www.qsl. net/w4xe/ rpttech/rpttech2 1.htm for some good information about how to do it. I have a UHF MASTRII with an IDA controller here that has been an ongoing project for many years. It keeps getting pushed to the back of the pile, mainly because the Maggiore repeater that the MASTRII is suppose to replace never failed. The IDA controller came in several versions, I have the repeater version in mine. You must leave the IDA controller in place because it supplies the 10 Volts DC that is required to run the MASTRII. I would leave the IDA controller functional, except for cutting the PTT lead to the transmitter. That way you can use the speaker in the IDA controller for a monitor. I plan to leave my IDA functional and have it as a back-up controller that I can switch online. 73, Joe, K1ike Michael Cox wrote: Ralph (and others) So is there a IDA equipped version the controller? If not, what does it mean that I have the IDA equiped version?
Re: [Repeater-Builder] Re: Can we tuning duplexer with this equipment?
Actually I have had excellent luck with just making sure there is no leakage from the signal generator or cable to the duplexer when using a talkie as the receiver for tuning a duplexer. After carefully tuning the pass adjustments, leave them alone when you have minimum loss and best SWR. The talkie receiver usually has enough sensitivity to dig the signal out of the noise for adjusting the notch. Tune for maximum noise while bringing the signal level up each time you make an adjustment to keep it noisy. My service monitor has too much signal leakage from the front panel and case to accurately tune the notch. I use an old analog Motorola signal generator which has a minimum of signal leakage as the signal source. Accuracy is preserved since I tune the generator to the talkie frequency. Just remember that any signal that leaks from the signal source will probably be picked up by the unshielded talkie and will add to the signal through the duplexer, and will yield the wrong settings for the notch. So carefully shielding the signal source and using good double shielded cable from the generator to the duplexer lets you get away with using a talkie with no shielding. I do use a 6 dB pad connected to the duplexer input and output with a 50 Ohm load on the unused port. If you can put a 50 Ohm load on the output of your signal source and not pick it up with the antenna on your talkie while the generator is set to maximum output, you have a good signal source for tuning a duplexer. 73 - Jim W5ZIT --- On Thu, 12/24/09, n...@no6b.com n...@no6b.com wrote: From: n...@no6b.com n...@no6b.com Subject: Re: [Repeater-Builder] Re: Can we tuning duplexer with this equipment? To: Repeater-Builder@yahoogroups.com Date: Thursday, December 24, 2009, 11:15 AM At 12/24/2009 07:42, you wrote: RG214 is good for this and you can still find short pieces on e-bay. It is double shielded silver plated braid. Bill N4XIR. Yes, but if the receiver/transmitte r used isn't well shielded, the double-shielded coax does no good. This is a big problem with using HTs for tuning duplexers, as most are poorly shielded. Bob NO6B
RE: [Repeater-Builder] Zetron 38A not sending reverse burst
I use several Z-38A controllers in ham applications. I get around the squelch crash problem by setting the Z-38A to stop sending a PL tone as soon as a user unkeys. The short tail is still there from the repeater, but the lack of a tone to a receiver lets the audio shut off while carrier is still present, and does not generate a squelch crash. I believe Nate calls this a 'chicken burst' though I have never heard that term before - A second benefit of shutting off the tone after a user unkeys is that it allows in-band links with no ping-pong effects due to the tails talking to each other. 73 - Jim W5ZIT --- On Wed, 11/18/09, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: RE: [Repeater-Builder] Zetron 38A not sending reverse burst To: Repeater-Builder@yahoogroups.com Date: Wednesday, November 18, 2009, 1:09 PM You have discovered one of many dirty little secrets that apply to aftermarket tone panels. When designing the 38A tone panel, and many other products, Zetron overlooked the fact that reverse burst is essential in the repeated audio. From a close examination of the 38A manual and schematics, it appears that it will decode CTCSS reverse burst and CDCSS turnoff code, and MAY generate CDCSS turnoff code, but I see no evidence that it can generate reverse burst. That alone is a major shortcoming! Zetron is not the only manufacturer that ignored reverse burst encoding when designing a community repeater controller. Instrument Associates, which produced the i20R On-site Repeater Controller for the Motorola GR1225 desktop repeater, did likewise. I did not realize this until I found that squelch crashes were immediately heard as soon as I put the i20R in service. Although some fans of the old Highway Patrol shows starring Broderick Crawford may enjoy the sound of a squelch crash, I do not, nor do any of my radio users. That i20R was pulled from service immediately, and put on the shelf! There are two different formats for CTCSS reverse burst STE (Squelch Tail Elimination) that are defined in TIA-603-C, the international standard for land-mobile radio performance and design. One format, used principally by Motorola, uses a 120-degree phase shift, while the other format, used by Kenwood and many others, uses a 180-degree phase shift. Since modern radios often use digital signal processing to encode and decode low-speed data (CTCSS and CDCSS), it is all too easy to design a circuit that responds perfectly to 180-degree phase shift but ignores 120-degree phase shift, and vice-versa. Zetron and others couldn't be bothered to create a CTCSS encoder that could be switched between the two reverse-burst formats, so they just ignored the problem. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of wspx472 Sent: Wednesday, November 18, 2009 10:15 AM To: Repeater-Builder@ yahoogroups. com Subject: [Repeater-Builder] Zetron 38A not sending reverse burst I am trying to get a repeater going using a 38A and find that it doesn't send reverse burst. I thought I saw that it did in the manual but upon looking again, all I see is where it responds to reverse burst. Does anyone know for sure if it is supposed to send reverse burst? If so, how do I get it to do it?
[Repeater-Builder] OT ACSSB - how does it work and is it possible for the hobbyist to scratch build
This problem (generating the 90 degree phase shift audio) is all that is keeping me from an experiment to generate a SSB signal using a little known technique I ran across in an old QST. It seems that a phase modulated FM signal can be combined with amplitude modulation with the audio 90 degree phase shifted and generate a SSB signal. The experiments referenced wound up with a SSB signal with full carrier. My first foray into sideband operation back in the late '50s was with a command transmitter with the grids modified to push pull and applying push pull audio to the screens. This generated a double sideband suppressed carrier signal. I suspect that I could modify a GE Prog transmitter by rewiring the grids of a 60 Watt final to push pull and applying push pull audio to the screens and applying 90 degree phase shifted audio to the normal phase modulation input would generate a SSB suppressed carrier signal. I suspect the pre-emphasis in the phase modulation circuit would have to be defeated, or does a phase modulation scheme automatically generate the pre-emphasis? 73 - Jim W5ZIT --- On Wed, 11/11/09, DCFluX dcf...@gmail.com wrote: From: DCFluX dcf...@gmail.com Subject: Re: [Repeater-Builder] acssb - how does it work and is it possible for the hobbyist to scratch build To: Repeater-Builder@yahoogroups.com Date: Wednesday, November 11, 2009, 9:02 PM I was playing with the ideas of making adapters, but it is supprisingly difficult to throw audio exactly 90 degrees out of phase over a broad frequency range.
Re: [Repeater-Builder] Re: repeater problems solved
This may have been addressed earlier, and if so I apologize. A GE Mobile Mastr II will generate an oscillation in the audio output stage if it is not loaded at all times. I don't remember the beginning of this thread, but if you are using a GE Mobile radio, this will wind up transmitting a tone on the repeated signal. I go one step further than putting a load on the speaker leads (10 Ohms) - I place a small teflon sleeve over the pin to the mother board that supplies B+ to the audio output stage after desense tests are completed. This removes B+ from the audio amp, and the sleeve can be removed if the audio output needs to be activated for later tests. 73 - Jim W5ZIT --- On Tue, 11/10/09, W3ML w...@arrl.net wrote: From: W3ML w...@arrl.net Subject: [Repeater-Builder] Re: repeater problems solved To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 10, 2009, 4:19 PM Thanks, I will check that. It is funny that out of the guys that hear it most are using mobile rigs. But, then the other night they said hey it is gone. Then ten minutes later it is back. All I know is with the fixes I was given by a great bunch of hams on here and the GE site and the with the new antenna and coax the repeater works like it is suppose to and sounds great to me. Of course, I am losing my hearing so I don't hear the tone. Thanks and 73 John --- In Repeater-Builder@ yahoogroups. com, wd8chl wd8...@... wrote: W3ML wrote: If it is not the grounded negative terminal I will just put in high pass filter on the PL cable. That should help reduce it or remove it. Thanks all. 73 John I wouldn't do that. FIRST-unplug the encoder audio out lead and see if it's still there (maybe the voltage in lead too, then ground). Then check levels. It should be between 500 and 800 Hz deviation. Then look for a good clean sine wave. Com-Spec SS-32's and TS-32's are known to have a less than perfect sine wave and can sound a bit raspy sometimes. If all that is OK, the problem is on the receiving end.
Re: [Repeater-Builder] Re: Linking Repeaters Remotely
The old Alinco DR-590 generated a reverse burst. I could always tell when a station was using one as the squelch noise went away immediately on a PL controlled repeater. 73 - Jim W5ZIT --- On Tue, 11/10/09, JOHN MACKEY jmac...@usa.net wrote: From: JOHN MACKEY jmac...@usa.net Subject: Re: [Repeater-Builder] Re: Linking Repeaters Remotely To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 10, 2009, 5:15 PM It's been since the late 1950's that reverse burst has been around for PL tones. So for over 50 years the ham manufacturers haven't gotten on board yet. -- Original Message -- Sure wish ham manufacturers would get on the ball on this feature and get it in the ham rigs. It's only been a decade or so now... all of our repeaters do it... the rigs don't know how to decode it, and I refuse to mess with chicken burst. I just use real radios, and it all sounds great!
Re: [Repeater-Builder] Wacom WP-639 coax lengths
Don't forget that the length of the coupling loops inside the cans contributes to the overall length of the coax. Ideally you would have a quarter wave from the Tee coupling the two sides of the duplexer together back to each can, including coupling loops. The idea is to have the pass side look into an open circuit (the quarter wave line going to the other side of the duplexer) at the Tee. 73 - Jim W5ZIT --- On Tue, 11/10/09, Kris Kirby k...@catonic.us wrote: From: Kris Kirby k...@catonic.us Subject: [Repeater-Builder] Wacom WP-639 coax lengths To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 10, 2009, 6:26 PM I'm working on re-fitting a Wacom WP-639 for re-use. There are two remaining jumpers on this four cavity filter set, located between the cavities on each respective side; there is no coax between the High side of the Low side, only coax between each of the two low side cans and the two high side cans. Due to the age of the jumpers, and with parts available on hand, I am replacing the jumpers with RG-142. My questions are these: Are the side pieces frequency specific or middle of the road. (i.e.: 146.01 and 146.61 MHz for each side or 146.31MHz for both)? How much length does a connector add to the length of the cable when making a frequency-specific or critical jumper? Is the distance between the high-side and the low-side of the duplexer 1/2 wavelength? I believe that from the tee in the middle of the set, there should be 1/4 wavelength to the first high-side can, and 1/4 wavelength to the first low-side can. Is this correct? I know that I have to factor for velocity factor, but I am at a loss as to what to add or subtract for crimp N-type or PL-259 connectors. Thoughts, comments, information are greatly appreciated. -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Re: Linking Repeaters Remotely
I used an in-band link to couple two VHF repeaters together, and have a Zetron Z38A controller that allows me to terminate the repeaters transmitted tone as soon as a user drops the input. That is all it took to keep the two repeaters happy. I never did have much luck with two users talking at the same time, so that has not been a problem. With the link we have, a user would have to be right on top of the repeater to overcome the link, so still just hear one user with a hetrodyne if another user is trying to talk, the same as if they were both trying to talk on the same repeater and one was stronger than the other. 73 - Jim W5ZIT --- On Tue, 11/10/09, larynl2 lar...@hotmail.com wrote: From: larynl2 lar...@hotmail.com Subject: [Repeater-Builder] Re: Linking Repeaters Remotely To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 10, 2009, 7:38 PM In-band RF linking on the user input frequencies is a kludge at best. It can double with users, and has other timing problems... Nate Duehr, WY0X n...@... Nate, just a comment on the above. We've used in-band on-channel (IBOC??) linking to a nearby repeater for weather nets for many moons now. It has worked absolutely great for us. Sure, it's not elegant; a dedicated link is probably the better way. And, users are going to double anyway. Can't get away from that. We've not found any timing problems you refer to... Laryn K8TVZ
RE: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band
Mike, I think the next step would be to try to get the paging operator to install an isolator on the output of his VHF pager for a temporary check. If he has one already, he could try putting two in tandem to increase the rejection of any RF coming back down the feedline from his antenna. What you may be hearing is a mix in his VHF transmitter with something else in his vicinity with an unstable frequency that is sweeping the mix through the VHF band. Years ago we had a problem in the Dallas area with a welder that produced an unstable carrier that would sweep through the 2 meter input frequencies of the repeaters in the area. The welder was located on the upper floors of the building in progress, and had a nice site for radiating the interfering signal. A foxhunt tracked that one down but it did not go away till the building was completed. Good luck with your QRM. 73 - Jim W5ZIT --- On Wed, 10/28/09, Mike Besemer (WM4B) mwbese...@cox.net wrote: From: Mike Besemer (WM4B) mwbese...@cox.net Subject: RE: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band To: Repeater-Builder@yahoogroups.com Date: Wednesday, October 28, 2009, 7:03 PM Strangely enough, I happen to be an O-O (as is the another club member, who sponsors the 145.110 repeater… which is also being interfered with) and have been in touch with our coordinator. He’s been very helpful in urging us along and providing us guidance (or reassurance) that we’re going about this the right way. He’s also indicated that he’s willing to go to ARRL HQ with it if we need to and then let them go lateral to the FCC. We had a great experience with Laura Smith about a year ago when we needed help convincing a banned user to stay off our systems. It took one letter to her (complete with recordings) and one phone call to get our banned user a nice letter from Laura reminding him that he really couldn’t afford to pay what she was prepared to charge him for using our repeater! So… I think that, armed with enough ammunition, we can go that route. However, I REALLY don’t want to. The fellow who owns the paging company has tried to work with us, and although it’s not going as fast as we’d like, I understand that he’s got a different motivation than we do. Aside from that, he helped us out with a professional climbing crew a couple of years ago, got us a good deal on a DB-224, and cut us a break on some hardline and connectors. The bottom line is, it’s not a relationship we want to end through a Federal intervention! That being said, I HAVE reminded him that he’s admitted that we’re carrying his data on our repeater, and whether or not it’s his equipment at fault or somebody else’s, HE’S going to be the first person they come looking for and it’ll be a terrible pain in his butt… and wallet. He acknowledges that fact. So… while I’d like for him to do some things differently… I get where he’s coming from and I appreciate that he’s helped as much as he has. On the other hand, if it turns out to be equipment that belongs to another company… I’ll drop a dime in a heartbeat if I don’t get satisfaction from them! 73, Mike WM4B From: Repeater-Builder@ yahoogroups. com [mailto:Repeater- buil...@yahoogro ups.com] On Behalf Of Paul Plack Sent: Wednesday, October 28, 2009 7:48 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band Mike, the interference is clearly not caused by your own rusty roof, and is both eggregious and easily documented. I know we hate to go there unless it's a last resort, but I'll bet the FCC is almost as tired of non-compliant pager systems as we are. Perhaps that technique would prove motivating. - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@ yahoogroups. com Sent: Wednesday, October 28, 2009 5:34 PM Subject: RE: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band I’m with ya on your third paragraph. We’ve worked well together so far, but we have very different techniques and motivations. .. .
Re: [Repeater-Builder] Repeaters vs RC
I operated an RC Aircraft on 53.5 for quite a few years, and the receiver in the model was wide open. The transmitter used on/off keyed pulses, with the carrier on the air most of the time and short interruptions (200 milliseconds) of the carrier being the control method. A reverse pulse position modulation scheme. I can tell you that operating the model within 50 miles of a channel 2 TV station would paralyze the receiver in the model as soon as it was airborne above a few hundred feet. I usually had time to recover the control when the model descended under the big signal from the TV transmitter, but it was a real pain to try to use it that way. The receiver IF was at 455 kHz and was only 5 kHz or so wide, but the transmitter used no bandwidth reduction and was probably at least 100 kHz wide. The low power and ground level antenna of the transmitter probably prevented interfering with other operations on six meters, but the potential was there. If the complainant is trying to control a model, there are lots of options now that do not include a six meter frequency, with the new 2.5 gig systems very cheap. No more frequency interference between models, since they can all operate at the same time with the spread spectrum control system. 73 - Jim W5ZIT --- On Sat, 10/10/09, MCH m...@nb.net wrote: From: MCH m...@nb.net Subject: [Repeater-Builder] Repeaters vs RC To: Repeater-builder@yahoogroups.com Date: Saturday, October 10, 2009, 11:58 PM Does anyone have any experience with repeater operation vs RC operation (Remote Control)? I have an RC operator who is 'raising a stink' about a repeater that is 30 kHz away from one of his RC channels. BTW, he also wants to 'compromise' by offering to relocate the repeater off the 52-54 MHz segment so they will not impact his RC operations. Some compromise, huh? I think he has the impression that RC channels are 100 kHz wide (they are standard AM) because the 6M RC channels are spaced at 100 kHz (53.100, 53.200, 53.3500, 53.400, Etc). I've told him they cannot be more than 10 kHz wide, if that, and that the FC repeater would be only 16 kHz wide, and at 30 kHz away the two can coexist without interference. Oh, the repeater in question is at least 20 miles away from his flying site. Any input out there? Exactly how wide is his AM signal? Thanks, Joe M.
Re: [Repeater-Builder] Passive fer wifi
I have a buddy who has a son living about a quarter mile away, and he mounted a router in a weatherproof fiberglass box on top of his 50 ft tower, and his son gets a good signal. Getting the router antennas up in the clear was the answer for that system. 73 - Jim W5ZIT --- On Tue, 9/8/09, numberone5call n...@bellsouth.net wrote: From: numberone5call n...@bellsouth.net Subject: [Repeater-Builder] Passive fer wifi To: Repeater-Builder@yahoogroups.com Date: Tuesday, September 8, 2009, 6:07 PM Curious; Has anyone tried a passive repeater to extend the distance of internet service. I have a daughter living in a house about 150 yards away. She has little to no service from my n-router. There is nothing to block the signal between us. What about connecting two yagis back to back and putting them on a pole halfway between us. Never tried it on vhf or uhf. Just wondering if anyone has tried it fer a wifi extension. Dennis no5c
Re: [Repeater-Builder] RC110 repeater controller
Good luck on getting any support at all on the RC110. It appears that Ken has abandoned the folks who bought one of those and you might as well chunk it in the trash. That is my take on it anyway. 73 - Jim W5ZIT --- On Tue, 9/8/09, wb7bts wb7...@yahoo.com wrote: From: wb7bts wb7...@yahoo.com Subject: [Repeater-Builder] RC110 repeater controller To: Repeater-Builder@yahoogroups.com Date: Tuesday, September 8, 2009, 9:27 AM Anybody heard from Ken AH6LE? I've sent him 2 e-mails in the last 2 weeks (ar...@arcomcontroll ers.com and ah...@arcom. com) and no reply so far.I need to send our controller in for firmware upgrade and voice chip programming. Thanks Phil
Re: [Repeater-Builder] Antenna SWR = Desense?
One of the local repeater operators used an antenna at the top of a 100 ft tower that got bent over during last winter storms. He put up a temporary antenna at the tower base and is experiencing some really bad desense with the low antenna. He is using a GE Mastr II base station repeater and had reasonable operation with little desense on the antenna 100 ft above the equipment. The antenna only 15 ft or so above the equipment now and has the bad desense problem. It would appear that the antenna is flooding the equipment with more RF than the shielding can handle. BTW, take a look at some of the previous posts on modifying a DB-224 by adding a 2 inch extension to each end of each dipole to bring it down into the ham band. The SWR does not go completely to 1:1, but does hit a minimum in the middle of the 2 meter ham band. No change to the harness was required to move the antenna frequency. 73 - Jim W5ZIT --- On Tue, 9/1/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] Antenna SWR = Desense? To: Repeater-Builder@yahoogroups.com Date: Tuesday, September 1, 2009, 2:03 PM Hi folks, Just a bit of an update... got the 6 cavity Telewave duplexer tweaked up - looks like it pretty much hit the specs in the data sheet. With a dummy load at the 'antenna' port, I used an iso-tee to inject a signal at both the receiver input, and between the antenna port the dummy load. With a weak signal, both places showed me that there was no desense. Very weak signal would hold in the repeater. However, putting the system on the antenna (a 150-160 mhz DB-224 100' horizontally 10' vertically separated) through a metal building fed with 7/8 heliax, there seems to be no end to the desense! The wattmeter shows 30 watts forward 3 watts reflected at the antenna port, if my math serves, it's less than 2:1. Can the less than 1:1 match be the culprit? Thanks, Tim W5FN __
Re: [Repeater-Builder] adjacent repeaters linked
Skipp, I have two VHF repeaters linked in-band. 146.92 with a remote base radio on the other repeater frequency at 145.45. I use GE Mastr II radios in both repeaters, and used a modified GE Mastr II mobile radio for the link. I removed the final amp from the link radio and use the 250 mW exciter through a low pass filter/antenna relay to a three element beam. The beam is about 15 feet below the DB-224 repeater antenna and causes no de-sense to the repeater. I am sure the repeater de-senses the link radio, but the result is not audible. The two repeaters are about 10 miles apart and are line-of-sight. The 145.45 repeater uses a directional antenna to cover a major highway in a canyon that is masked from the 146.92 repeater in several places. 73 - Jim W5ZIT --- On Mon, 8/31/09, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] adjacent repeaters linked To: Repeater-Builder@yahoogroups.com Date: Monday, August 31, 2009, 3:17 PM I pulled off linking two adjacent 224MHz Repeaters. The repeaters are on different 30 mile distant mountain top sites. One repeater has an on-band linking radio (Alinco DR-235) set up on the adjacent frequency. As an example... 224.960 and 224.940MHz. With enough physical isolation, filtering and setup... much to my surprise it works pretty well. The owner wants to now park IRLP on it and waste everyone's time. But they are his repeaters... On toward part 2. s.
Re: [Repeater-Builder] DB-224 Matching
I have modified several of the 155 mHz center frequency DB-224 antennas to the ham band. I found that it takes a 2 inch extension to each end of each dipole to move them down. My mod was done empirically by taking a single dipole and hooking it to an analyzer and finding the original center frequency to be ~ 155 mHz. With the 2 inch extension added to each end, the center frequency moved down to 146 mHz. I did not have to modify the harness. I make the extension out of a scrapped TV antenna with rolled tubing elements. I flatten the tubing so that it can be wrapped around the dipole at the center point of each end and put a single screw through the wrapped flat portion of the TV tubing to clamp it to the dipole. When all assembled, I measure the distance to the end of the tubing from the 224 dipole and cut the extension to 2 inches. This moves the center frequency of the completed DB-224 mod down to 146 mHz from 155 mHz. 73 - Jim W5ZIT --- On Wed, 8/19/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB-224 Matching To: Repeater-Builder@yahoogroups.com Date: Wednesday, August 19, 2009, 8:40 AM In my quest to get rid of desense with the Quantar, someone mentioned that having the 'wrong' antenna could make the desense worse. I've got a DB-224 - not the 'ham' version, but the 150-160 MHz version, and there is a bit of a mismatch. Has anyone ever had any desense that they could attribute to less than perfect matching? (I'm not talking about a gross problem, like one of the elements broken, etc) Has anyone built a 'tuner' for that version of the 224, so that the transmitter/ duplexer pair would see a better SWR? If this thing ever gets up, it's gonna be perfect! :-) Thanks, Tim W5FN
Re: [Repeater-Builder] Re: DB-224 Matching
The oxidation problem was what I was trying to avoid with my wrap and clamp scheme. I just use galvanized hardware to clamp the extension since it is an aluminum to aluminum connection (no dissimilar metal) to the 224 element. Oxidation of the screw and nut are not in the contact path so it does not matter. Also, the clamp connection is at the highest impedance point on the dipoles, so again, it is not a high current point, so the clamp scheme does not carry much current through the clamp. Not drilling holes in the existing antenna was also a goal, as I have modified several antennas on site with a tower climber doing the install. Keeps it simple! 73 - Jim W5ZIT --- On Thu, 8/20/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] Re: DB-224 Matching To: Repeater-Builder@yahoogroups.com Date: Thursday, August 20, 2009, 10:16 AM Hi Jim, That's what I was looking for! Do you have any oxidation/connectio n issues where the tubing is wrapped around screwed together? Perhaps drilling a hole through the original element for connection might be better. Just wondering. Thanks for the tip!! Tim W5FN --- In Repeater-Builder@ yahoogroups. com, Jim Brown w5...@... wrote: I have modified several of the 155 mHz center frequency DB-224 antennas to the ham band. I found that it takes a 2 inch extension to each end of each dipole to move them down. My mod was done empirically by taking a single dipole and hooking it to an analyzer and finding the original center frequency to be ~ 155 mHz. With the 2 inch extension added to each end, the center frequency moved down to 146 mHz. I did not have to modify the harness. I make the extension out of a scrapped TV antenna with rolled tubing elements. I flatten the tubing so that it can be wrapped around the dipole at the center point of each end and put a single screw through the wrapped flat portion of the TV tubing to clamp it to the dipole. When all assembled, I measure the distance to the end of the tubing from the 224 dipole and cut the extension to 2 inches. This moves the center frequency of the completed DB-224 mod down to 146 mHz from 155 mHz. 73 - Jim W5ZIT
Re: [Repeater-Builder] Repeaters and Water Towers
We put a repeater in the equipment room right under the water tank about 150 ft above the ground back in the 70's. It is a great environment since the water in the tank is a great heat sink. It assumes the average temp of the outside air (integrates the temp over months at a time) and keeps the air temp in the equipment room very cool in the summer and warm in the winter. The repeater is still operating on this tank. The only problem we had was when the city decided to sand blast the tank and did not let us know. The dust was over an inch thick on every horizontal part of the repeater, and was inside our shield boxes (tiny holes, but the crap sifted through). They bought us some new circuit board assemblies for the transmitter and receiver and we installed them in the old shielded boxes. We did manage to clean up the duplexer without having to tune it again. Be sure to keep up with any maintenance on the tank to make sure this does not happen to you - 73 - Jim W5ZIT --- On Thu, 8/20/09, kc8fwd kc8...@hotmail.com wrote: From: kc8fwd kc8...@hotmail.com Subject: [Repeater-Builder] Repeaters and Water Towers To: Repeater-Builder@yahoogroups.com Date: Thursday, August 20, 2009, 4:03 PM Hello, Has anyone had experience with repeaters at water tower sites now that homeland security is involved? I would like to hear your experience. Thanks Mike KC8FWD
Re: [Repeater-Builder] Re: An advocate for a little audio compression
Our engineering prototype parts guy had a sign behind his desk that said: Failure to plan ahead on your part does not constitute an emergency on my part 73 - Jim W5ZIT --- On Sun, 8/16/09, Paul Plack pl...@xmission.com wrote: From: Paul Plack pl...@xmission.com Subject: Re: [Repeater-Builder] Re: An advocate for a little audio compression To: Repeater-Builder@yahoogroups.com Date: Sunday, August 16, 2009, 9:19 AM No, John, I was never been a CE, but a PD several times. This same guy was the first to have on his door a sign I've since seen several other places: Procrastination on Your Part Does Not Constitute An Emergency on My Part 73, Paul, AE4KR __
Re: [Repeater-Builder] Re: Com Spec TS-64 DS
Skip, here is a link to my most recent experience with the TS-64: http://sbarcnm.org/forum/index.php?action=dlattach;topic=108.0;attach=154 This was the version sold for the GE Mastr II. I had to OR two receivers for the transmit CTCSS (repeater receiver and link receiver). I used the filtered audio supplied by the TS-64 to supply the audio input to the controller so I would not have problems with the input/output CTCSS beat frequency problem. I routed audio and control signals out the unused frequency select pins directly adjacent to the TS-64 board for access on the rear of the unused GE Mastr II Molex connectors with no alteration or soldering to the Mastr II repeater. The repeater has been in service for a year now with this configuration and the CTCSS decode and control works all OK. I found the TS-64 ideally configured to work in the repeater environment, and did not have to add any wires to the standard GE harness to complete the repeater install with a link radio. 73 - Jim W5ZIT --- On Fri, 8/14/09, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] Re: Com Spec TS-64 DS To: Repeater-Builder@yahoogroups.com Date: Friday, August 14, 2009, 11:06 AM Any of you worked with a Com Spec TS-64 or TS-64 DS lately? I have two topics to mention in this post. The first is the dip switch daughter board under the TS-64 making the same unit the TS-64 DS. Anyone have any additional information regarding the daughter board? Anyone used the Daughter Board for applications other than the dip switch? The second bit of fun (topic) is related to the Voice Audio CTCSS Filter being tied to the Discriminator Input. The old TS-32 boards has a separate input for the Voice Audio Filter and the Discriminator Input. Seems kind of a shoot yourself in the foot limitation when you permanently connect the two different inputs together. Anyone run into the above issues and what did you do about it? cheers, skipp
Re: [Repeater-Builder] Re: An advocate for a little audio compression
One way might be to set the transmitter deviation to 5 kHz for a 2.5 kHz deviation input signal. Set the VOX threshold to trip at about 3 kHz input deviation and use it to switch in a 6 dBV pad to cut the deviation back down. A fast attack VOX with a slow release would keep the audio from pumping up and down. 73 - Jim W5ZIT --- On Wed, 8/12/09, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] Re: An advocate for a little audio compression To: Repeater-Builder@yahoogroups.com Date: Wednesday, August 12, 2009, 10:54 AM n...@... wrote: Yes, but increasing the user's deviation to the proper level would help a lot more. A lot of people have voices, which are not considered Radio or Broadcast Quality in both pitch and volume. Add a little mic shyness and you're often stuck with lower average deviation. Trying to inform and fix users about close talking the mic at higher volume levels does a good job of scaring some folks off. A simple VOX ANDed with the COS would take care of that. Bob NO6B I would be interested in a description of the above... cheers, s. At 8/11/2009 08:28, you wrote: Hi Paul, One has to deal with reality... while you might consider a soft talking person not properly trained, more than a fair number of users don't have a booming voice. In a larger number of cases a little bit of added audio compression/ limiting helps resolve the low (higher/soft pitch) perceived volume level difference. The brain is pretty good about picking a voice from background audio so just being able to hear the receive audio better is going to help.
Re: [Repeater-Builder] Re: 2M Vertical Dipoles
There is a definite dielectric effect for slipping an antenna inside a PVC pipe. Here are a couple of antennas that I build to insert inside PVC and both have to be final tuned while inserted inside the support pipe. http://sbarcnm.org/forum/index.php?topic=83.0 http://sbarcnm.org/forum/index.php?topic=58.0 I built one version of the first one listed to slip inside a fiberglass radome from a defunct commercial antenna using RG-213 and one half inch copper tubing for the sleeves. I had to use a shorted matching stub to get a decent SWR from this setup. 73 - Jim W5ZIT --- On Wed, 8/12/09, AJ aj.grant...@gmail.com wrote: From: AJ aj.grant...@gmail.com Subject: Re: [Repeater-Builder] Re: 2M Vertical Dipoles To: Repeater-Builder@yahoogroups.com Date: Wednesday, August 12, 2009, 10:05 AM Does really PVC absorb or RF or just act as a dielectric? The reason I ask is I'm looking at encasing an antenna project for the sake of weatherproofing and PVC would fit the bill rather easily. 73, AJ, K6LOR On Mon, Aug 10, 2009 at 9:49 AM, AA8K73 GMail aa8...@gmail. com wrote: AJ, if you replace the steel mast with a fiberglass one, won't you still have the metallic feed line there? Doesn't PVC absorb RF? 73, Mike AJ wrote: On this same topic of the mast-less Antennex/Laird dipole arrays, has anyone attempted to top mount these from a fiberglass mast to minimize interaction with the normal steel pole? I have quite a few surplus fiberglass poles left that would likely work, even for side mounting on 1/2 wave spacing from the tower... On that same note, does anyone have construction plans for a dipole array (not necessarily folded dipoles)? I remember seeing a set of plans somewhere quite a while ago - we're thinking of constructing one but encasing the dipoles in fiberglass or PVC to try to protect from the weather and debris at our site (top of a large farm field)... 73, AJ, K6LOR
Re: [Repeater-Builder] Re: 2M Vertical Dipoles
I see that YAHOO added spaces to the links in my last post. Remove the spaces to make the links work. 73 - Jim W5ZIT --- On Wed, 8/12/09, Jim Brown w5...@yahoo.com wrote: From: Jim Brown w5...@yahoo.com Subject: Re: [Repeater-Builder] Re: 2M Vertical Dipoles To: Repeater-Builder@yahoogroups.com Date: Wednesday, August 12, 2009, 10:43 AM There is a definite dielectric effect for slipping an antenna inside a PVC pipe. Here are a couple of antennas that I build to insert inside PVC and both have to be final tuned while inserted inside the support pipe. http://sbarcnm. org/forum/index.php?topic=83.0 http://sbarcnm. org/forum/index.php?topic=58.0 I built one version of the first one listed to slip inside a fiberglass radome from a defunct commercial antenna using RG-213 and one half inch copper tubing for the sleeves. I had to use a shorted matching stub to get a decent SWR from this setup. 73 - Jim W5ZIT ,___
Re: [Repeater-Builder] 2M Vertical Dipoles
I posted a note on this a while back, but will recap here. I mounted four dipoles from a DB-224 on one leg of two sections of Rhon 25 and mounted the tower on an antenna range turntable. The pattern was a perfect circle, using DB Power readings around the 360 degrees. I thought I remembered the offset being 3 dB, but I must have been mistaken since it was pointed out that could not be the gain off the back of the antenna mounted this way. All four dipoles were stacked vertically on one leg of the tower and oriented directly away from the tower. The gain was measured as 9 dBd in the favored direction, coming down to 6 dBd at 90/270 degrees, and I thought I remembered the gain as 3 dBd off the back side of the tower, but it must have been a lower number. In any case, looking at the plot it appeared to be a perfect circle with an offset center. The center offset must not have been 3 dB. I was surprised that the tower did not cause a null off the backside, just caused a reduction in gain in that direction. This plot was submitted to the FCC to get repeater license WR5ADU and WR5ADV back in the '70s when antenna patterns for a repeater had to be submitted. 73 - Jim W5ZIT --- On Sun, 8/9/09, MCH m...@nb.net wrote: From: MCH m...@nb.net Subject: Re: [Repeater-Builder] 2M Vertical Dipoles To: Repeater-Builder@yahoogroups.com Date: Sunday, August 9, 2009, 6:33 PM Lots of comments on the unidirectional pattern which I suggested might not work well. Any comments on having the elements on one side of the tower right on the leg? Joe M. n...@no6b.com wrote: At 8/9/2009 05:47, you wrote: As frequency decreases, so does the importance of keeping the dipoles exactly above one another. This is why you can get away with mounting the bays of a LB array around a smaller tower (like Rohn 25) and still have very good omni-directional performance. Positioning the bays around a central supporting mast of a UHF array creates considerable pattern distortion and gain is lost. I once modeled this arrangement in NEC-Win: the resulting pattern looked like a warped pancake. On-horizon gain was all over the place. Bob NO6B - - -- Yahoo! Groups Links
Re: [Repeater-Builder] Too stupid to run Google??
A method of taking the COR I have used on a radio that I did not have the internal schematic is to locate the wires going to the BUSY LED on the front panel and insert the diode of an Opto Isolator in series with the busy LED and take the COR from the transistor of the Opto Isolator. You can get either a positive going COR by connecting the collector to a positive supply and taking the signal from the emitter, or a negative going COR by connecting the emitter to ground and putting a pull up resistor to the collector with the signal taken from the collector. 73 - Jim W5ZIT --- On Tue, 7/28/09, Scott Zimmerman n3...@repeater-builder.com wrote: From: Scott Zimmerman n3...@repeater-builder.com Subject: [Repeater-Builder] Too stupid to run Google?? To: Repeater-Builder@yahoogroups.com Date: Tuesday, July 28, 2009, 3:38 PM I *know* this is out there somewhere, but apparently I am WAYYY to stupid to run google right now. I have a TM-331 I am making in to a single frequency remote base. Where can I find a COR in this radio? I see TONS of references to using an RBI-1, but I am only using ONE channel. Apparently I have been out in the sun too long or something. Maybe Google is having trouble reading my mind... Yea, That's it!! Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531
Re: [Repeater-Builder] DB Products VHF UHF on same mast?
I operate an antenna with a full size DB-224 and an 8 dipole 440 antenna on the same mast and found that the 2 meter transmitter does not bother the 440 receiver, but I do get some desense with the 440 transmitter into the 2 meter radio. An extra bandpass cavity on the 2 meter receiver cleared that up. GE Mastr II on both bands. I think that the 2 meter dipoles can absorb more power from the 440 antennas than the other way around, since the third harmonic is resonant on the 2 meter dipoles. I have also operated a DB-224 on 440 with some success. I tried a diplexer to combine the two antennas to one feedline without much success. I wound up using a separate feedline for each antenna and it worked much better. 73 - Jim W5ZIT --- On Mon, 7/20/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB Products VHF UHF on same mast? To: Repeater-Builder@yahoogroups.com Date: Monday, July 20, 2009, 10:11 PM I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN
Re: [Repeater-Builder] Re: DB Products VHF UHF on same mast?
Someone on this list published an analysis of a DB-224 used on 440 and it showed some interesting results. The antenna exhibits a bunch of narrow lobes in the vertical plain, and has a very narrow vertical angle right on the horizon. For your purpose, I think you will find that it will work just fine with the diplexer at the repeater end splitting the antenna to the repeater and a 440 receiver. We operated a 2 meter and a 440 repeater through a diplexer to a Comet dual band antenna and as long as the two frequencies were not harmonically related, the two repeaters seemed to get along just fine on the one antenna. 73 - Jim W5ZIT --- On Wed, 7/22/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] Re: DB Products VHF UHF on same mast? To: Repeater-Builder@yahoogroups.com Date: Wednesday, July 22, 2009, 10:17 AM Hi Jim, Thanks for the info. I will probably not put the 440 antenna up - I don't plan on having a 440 repeater out here, just need to receive a control signal. So I'll probably put the diplexer at the bottom just use the db-224 for 440 receive. Tim W5FN --- In Repeater-Builder@ yahoogroups. com, Jim Brown w5...@... wrote: I operate an antenna with a full size DB-224 and an 8 dipole 440 antenna on the same mast and found that the 2 meter transmitter does not bother the 440 receiver, but I do get some desense with the 440 transmitter into the 2 meter radio. An extra bandpass cavity on the 2 meter receiver cleared that up. GE Mastr II on both bands. I think that the 2 meter dipoles can absorb more power from the 440 antennas than the other way around, since the third harmonic is resonant on the 2 meter dipoles. I have also operated a DB-224 on 440 with some success. I tried a diplexer to combine the two antennas to one feedline without much success. I wound up using a separate feedline for each antenna and it worked much better. 73 - Jim W5ZIT --- On Mon, 7/20/09, tahrens301 tahr...@... wrote: From: tahrens301 tahr...@... Subject: [Repeater-Builder] DB Products VHF UHF on same mast? To: Repeater-Builder@ yahoogroups. com Date: Monday, July 20, 2009, 10:11 PM I've got a DB-224 that is going up the tower in a while when I get the hardline, but control issues have changed from land line to 440mhz control. So I need 2 antennas. Today I saw a hybrid DB antenna, effectively a 224, plus a 16 element DB, all on the same mast. Is this something that can be done without having each antenna interact with the other? Sounds like a good idea to me. Just curious, Thanks, Tim W5FN
Re: [Repeater-Builder] Convert 406-420mhz Mastr II to ham band
Dave, I have moved about 5 stations that were in Forrest Service use around 417 mHz, and have a few suggestions. Buy a mobile 88 split receiver and don't attempt to change the 77 receiver front end. I modified three of them by removing one quarter turn from each of the helical resonators, and it is just not worth the effort. The mobile 88 split receiver will interchange with your 77 split receiver. The exciter tuned right up, with no changes to any component values on each of the 5 that I moved. If you buy a mobile for the receiver, the exciter will also exchange with your 77 exciter. The 77 split amp works just fine up in the ham band except for the low pass filter on the board with the T/R relay on the output of the amp, if you have one without the T/R relay. Remove the filter cover and parallel a #18 buss wire with the existing wire that connects from the input cap to the output cap across the three shunt caps. This lowers the inductance slightly and will allow you to pass full power to the output. If the amp has a matching circuit - a simple PI Network on the output, be sure to tune it up when you are through with the LPF modification. Don't tune for max power - tune for a null on the reflected power test point provided on the matching board. Not all amps have the matching board, but pay attention if yours has one. None of the other components in the station change with the 77 to 88 split change. In fact, the audio squelch board from a VHF mobile or station will interchange with the 77 you are moving to an 88 split. By all means - buy or trade for an 88 split receiver and don't attempt the quarter turn coil removal in the helicals. It just is not worth the effort to heat the cavity for the heilcals enough to remove the coils and then get them resoldered in the right place. The osc-multiplier board will not go to high side injection like I prefer on a UHF M2. You would have to stay with low side injection, and beware the pitfall in the receive frequencyarea described in a note on the repeater builder site. I had a low side injection repeater operating on 443.9 that had the problem until I changed to high side injection. Good luck on your conversion. 73 - Jim W5ZIT --- On Sun, 7/19/09, Dave Cochran d...@n0trq.com wrote: From: Dave Cochran d...@n0trq.com Subject: [Repeater-Builder] Convert 406-420mhz Mastr II to ham band To: Repeater-Builder@yahoogroups.com Date: Sunday, July 19, 2009, 10:05 AM Okay guys, I might be biting off more than I know here, but I've been tasked out to try to get this accomplished for a new fledgling group of hams here. How much effort is really involved in converting a 406-420Mhz Mastr II machine (combination ending in 77) up to the ham band? Need to start learning more somewhere and this seems like a good avenue to take. I'm sure someone must have written up a step by step guide for re-tuning, I just have not found it yet. A point in the right direction would be helpful. Thanks, Dave - N0TRQ
Re: [Repeater-Builder] Sinclair Hybrid Ring Duplexer
I helped a buddy check a set of Sinclair VHF Hybrid Ring duplexers a couple of years ago, and was really impressed by the performance of that 4 cavity duplexer. We had +20 dB available at the output of the signal generator and could not see the bottom of the notches on a 80 dB spectrum analyzer. We wound up modulating the signal generator with a 50 kHz wide FM signal to see the sides of the notch, and could tweak the adjustable line to an equal signal either side of the notch with the FM on the signal generator. I estimate the isolation of each half of that duplexer was close to 120 dB and had less than 2 dB insertion loss. Stay after that duplexer, it is a winner, but they are sure a b to tune. Any leakage in the cables to your test equipment will totally ruin the results. 73 - Jim W5ZIT --- On Sun, 7/19/09, de W5DK w...@gvtc.com wrote: From: de W5DK w...@gvtc.com Subject: [Repeater-Builder] Sinclair Hybrid Ring Duplexer To: Repeater-Builder@yahoogroups.com Date: Sunday, July 19, 2009, 11:58 AM Yesterday, with a buddy, I attempted to tune my first set of hybrid ring duplexers. I have successfully tuned many sets of duplexers and didn’t expect to have any trouble with a minor freq move. I have read and understand the theory behind the design. http://www.repeater -builder. com/antenna/ hybridring. html In practice I saw some unexpected results. My buddy has a new to him HP 8935 (SA/tracking) so we started off using it. I have a HP8921A that we also used. We used good shielded cables, 3db pads x3 and good dummy loads, etc. We started off with a working good on 145.23/144.63 set of duplexers. They were taken off the air and brought to me to be moved up to 146.76/16. I am sure these were many megs up originally and were modified to get down to 145.23. It appears only the termination stub coax lengths were changed and they are longer than the 144-146 instructions suggested as starting points. So I understand the rings/stubs and antenna port for each side may not be *perfect* but they were performing and we are only moving them up a meg or so (towards the original harness freq).. First thing off the bat we looked at the current high pass side and it looked like it only had 45 db separation, the low pass looked better at 65, other wised shaped pretty good. How could they be working good all these years like that? Reading the HP correctly? Yes. H. We used the Sinclair instructions to retune them substituting our tracking gen/SA test gear for the instructions sig gen/receiver. We followed the laborious instructions carefully (course tune/fine tune) and ended up with similar separation numbers on the new freqs. Hmmm, must be something quirky with the 8935, fired up the 8921 and it showed we had even less separation. Half what the 8935 showed. When placed into station service into a dummy load, they didn’t work, I’ll spare you the numbers. Time for a beer. We fiddled with it some more using both service monitors, a talkie and a bird and didn’t move anything much, everything was still peaking/nulling. It has been my experience that with 3db pads on the 3 ports, patch cable lengths to test gear are not critical, I’m beginning to think this style ring system is finicky. After sleeping on it I am thinking we are really close. I’m guessing we are unable to see the ring cancelation/ null/pass with the gear we are using even though we are able to see the pass and reject peaks during our steps? I’m looking for suggestions on what I’m missing and why we can’t we use our expensive test gear to fine tune these freaks? 73 Don W5DK
Re: [Repeater-Builder] Need circuit -- COS Sense AF Amplify [1 Attachment]
Here are a couple of simple circuits to do what you want. Use a well filtered source of +V for the audio amplifier to keep from developing some hum on the output. Any voltage source from +5 to +12 should work. Adjust the variable resistor to set the gain of the audio amplifier. 73 - Jim W5ZIT --- On Mon, 7/13/09, John Transue jtran...@cox.net wrote: From: John Transue jtran...@cox.net Subject: [Repeater-Builder] Need circuit -- COS Sense AF Amplify [1 Attachment] To: Repeater-Builder@yahoogroups.com Date: Monday, July 13, 2009, 8:42 AM [Attachment(s) from John Transue included below] I need to interface a link receiver (Icom F221S) with an ACC RC-850. This presents two problems. First, the Icom receiver uses active low COS, and the RC-850 doesn't seem to have a means to select the sense of a link receiver. The repeater receiver (Midland BaseTech II) uses active high COS. Second, the discriminator audio output from the Icom is about 0.6 Vp-p, but the RC-850 hardware manual says the audio input should be between 1 and 5 Vp-p. I have posted the first problem to the ACC group but have received no reply. Yes, the ACC manual says to insert a 47K resistor in a specified place to increase sensitivity. I can do this but it requires I take the repeater out of operation for a day or so. It occurs to me that a circuit to reverse the sense of the COS might be available from this group. Also, a simple amplifier circuit could solve the AF level problem. I know this is all elementary, but I am not competent to design these simple circuits. I will gladly build them. I would appreciate any help you can provide on the design. Thanks. John Transue AF4PD
Re: [Repeater-Builder] DB-224 patterns on side of tower.
Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT --- On Tue, 6/30/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Tuesday, June 30, 2009, 2:35 PM Hi Folks, We are putting up the DB-224 on the side of the tower, which is one of those large 3 legged towers. (like you see at microwave telephone sites). I have the DB-products data sheet on the 224, and it has some plots for side mounting on the tower. The plot in question is the 224E (all in line, pointed away from the tower). According to DBprod, it would give the appropriate pattern for our desired area. However, one of the old salts here (who has final say-so) says that you really have to put some left and right angulation on the elements to get that pattern. I guess the real question is how positioning on the side of the large tower affects the pattern - if the elements are directly perpendicular to the tower leg, versus having some rotation on the leg. I'm thinking that we will probably just have to experiment with what we get per old-salt's method see how it works. Anybody have any other ideas? Thanks, Tim W5FN
Re: [Repeater-Builder] DB-224 patterns on side of tower.
We used a Scientific Atlanta turntable on top of a 5 story building with the signal source ground mounted about 500 ft away. The turntable was tilted to be at right angles to the signal source. The E-Systems range was available at the time. WR5ADU and WR5ADV were issued with that antenna pattern submitted. Many folks just drew a circle and submitted that along with the application, but we throught they were serious about an actual antenna pattern. 73 - Jim W5ZIT --- On Wed, 7/1/09, Chuck Kelsey wb2...@roadrunner.com wrote: From: Chuck Kelsey wb2...@roadrunner.com Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Wednesday, July 1, 2009, 5:59 PM Did you do any others? I'm guessing that this was done on the Decibel antenna range, maybe? Chuck WB2EDV - Original Message - From: Jim Brown To: Repeater-Builder@ yahoogroups. com Sent: Wednesday, July 01, 2009 6:46 PM Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT
RE: [Repeater-Builder] DB-224 patterns on side of tower.
I won't try to argue with you Jeff, but those patterns might still be on file at the FCC somewhere. This test was done on a professional antenna range by the same folks who verified all the antennas that we mounted on the airborne reconnaissance aircraft for the military. We have mounted complete fuselage sections on this test range and done both horizontal and vertical patterns. We only did the horizontal pattern for the DB-224 elements mounted directly to the Rhon 25 sections. The gain figures I quoted are dBd reference the dipole mounted in place of the DB-224 before the test. The Scientific Atlanta turntable was connected to a circular strip chart and the amplitude measurements were recorded directly to the strip chart which was submitted. The turntable was mounted on top of a five story building with the signal source about 500 feet away mounted near the ground. The tilt angle between the source and antenna to be measured is to prevent ground reflections from entering into the results. I did not attempt to do any measurements to make sure it was a circle, but it sure looked like a circle to me - with the 3 dB offset from the center toward the direction the dipoles were pointed. Again, the results were perfectly smooth with a 9 dB gain in the direction the dipoles were pointed, varying very smoothly with no nulls or dips to 3 dB gain in the direction through the tower oposite the dipoles. I don't see your point on where the energy comes from to make the extra 3 dB gain, as it obviously comes from the 3 dB reduction in gain on the back side of the tower compared to an omni antenna. 73 - Jim W5ZIT --- On Wed, 7/1/09, Jeff DePolo j...@broadsci.com wrote: From: Jeff DePolo j...@broadsci.com Subject: RE: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Wednesday, July 1, 2009, 7:11 PM Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. I'm not trying to pick a fight here, but this seems to defy the laws of physics. There would have to be nulls that were quite deep elsewhere in the pattern aside from the four azimuths you cited if those values were indeed valid. Think about this, a grossy simplified example that would be difficult to achive in the practical world, but valid in theory nonetheless. Say you have an omnidirectional antenna that has some gain due to elevation pattern compression (for example, a stacked dipole array like we're talking about). Or it could even be an inefficient antenna (rubber duck) that has negative gain relative to a dipole. The omni gain isn't really important, it just serves as reference, but for sake of argument say it's a 4-bay dipole array that has 6 dBd gain omni. So, 6 dBd would be 0 dBr (r=reference) . Now we do something to alter the azimuth pattern which results in there being a 90 degree arc that has 9 dBd (+3 dBr) gain uniformly over that arc, two 90 degree arcs that have 6 dBd (+0 dBr) gain uniformly over those arcs, leaving a fourth 90 degree arc. What's the gain over that remaining 90 degree arc assuming it, too, is unform across its 90 degrees? If you answered 3 dBd (-3 dBr), you're wrong. If you answered 0 dB (-6 dBr), you're wrong. In fact, you'd be infinitely wrong if you answered anything other than negative infinity dB's (i.e. ZERO radiation). Using your examples/numbers above, and assuming a perfectly round pattern offset from the center by 3 dB plotted as a typical logarithmic polar plot, you're saying that over an arc of 180 degrees (the forward direction) the gain was a minimum of 6 dBd (0 dBr), and a maximum of 9 dBd (+3 dBr), correct? That would be impossible as you couldn't take enough power out of that remaining 180 degree arc on the backside to ever balance out the forward gain you claim to have achieved! There would have to be other deep nulls elsewhere in the pattern for there to ever being a chance of those gain values being being possible. If it helps to understand this better, think of a two-way power divider. A perfect two-way power divider would yield -3dB at each of its output ports relative to the input signal. Let's say the input power is 0 dBm, so at each port we have -3 dBm. Now say we modify the power divider so that one port is 3 dB hotter than what it was originally, resulting in 0 dBm coming out this hot port. What's left
Re: [Repeater-Builder] Exec II input problem
What are you using for a signal generator? Some generators leak a lot of signal and might have more than .35 uV of signal radiated on the outside of the coax. When you break the shield path, this higher signal level might get to the radio. Another post mentioned that the RCA connector uses a short pin. I use a BNC to RCA connector with the center pin cut back to match the radio internal connectors to avoid problems in this area. 734 - Jim W5ZIT --- On Thu, 5/28/09, wb8art wb8...@netzero.net wrote: From: wb8art wb8...@netzero.net Subject: [Repeater-Builder] Exec II input problem To: Repeater-Builder@yahoogroups.com Date: Thursday, May 28, 2009, 4:02 PM Wonder if anyone has had this problem and know what the problem is. I am working on a GE Exec II repeater (converted mobile) which has no Comb no. I any case the issue is that if I move around the cable feeding it with a generator I was seeing a change in the recieve. I went directly to the RCA jack, and then found that just making connection with the center pin, I have about 10 to 20db stronger recieved signal than when I push it all the way in making the ground connection. This is a mobile and the RF deck is no. is 19D417075G14 rev A covered by LBI30032E. This shows a option of either non floating ground or floating ground input. This one is a non floating ground one. Might have been changed but I have know knowledge of its history. The RCA jack center pin connects directly with a wire thru a hole to the first helical and I have looked and can see no connection issues and measures a short with an ohm meter. I even reheated the solder joints and no change. Anythoughts would be appreciated. Randy
Re: [Repeater-Builder] OT - recommendation needed - battery charger
Wall-Mart sells a pretty good charger for this purpose. It is rated at 2, 4, or 6 amps (set by push buttons) and falls back to a float charge (13.5 V) after bringing the battery up to about 14.8 Volts. I have one on the backup battery for a Mastr II repeater that has a backup circuit built into the power supply, but does not have a charger in the power supply. We read the Zetron for a report to the village quarterly (they supply the repeater site) and the procedure is to put the charger in the 6 amp position (stir the electrolyte) every time we open the cabinet doors. It also gives an indication that a power outage has occurred, since the charger will be showing a 2 amp charge (default value) instead of the 6 amp setting it was left in. If the battery has completely run down, a 2 Amp charger usually will not completely charge the battery. The 6 Amp rate however, will bring the battery up to full charge before falling back to the float voltage. The charger is built by Slumberger (SP) and should keep his car battery in good shape. 73 - Jim W5ZIT --- On Fri, 5/22/09, Mike Morris WA6ILQ wa6...@gmail.com wrote: From: Mike Morris WA6ILQ wa6...@gmail.com Subject: [Repeater-Builder] OT - recommendation needed - battery charger To: Repeater-Builder@yahoogroups.com Date: Friday, May 22, 2009, 3:31 PM Got a friend who is laid up with back problems. His car has been sitting for several months between uses. He has already lost one battery from sitting idle. He wants to purchase something packaged like a trickle charger that can be connected to the battery and left there (maybe even semi-permanently with a cord hanging out the grille). Does anyone have a suggestion for such a product ? Maybe one of the desulfator devices ? Mike WA6ILQ
Re: [Repeater-Builder] Re: Two questions
The connector you are looking for is on the IF-Audio-Squelch board. The connector is numbered with pin 1 below the notch and pin 5 opposite the notch. The signal you want is present on pin 1. It is also present on the interface connector for the module on pin 4. This is the signal level at the output of the second crystal filter and is very low until the signal is very strong. The documentation for an IF-Audio-Squelch board is available on the Repeater-Builder.com site. Look for LBI 19D417707. --- On Wed, 5/13/09, w4sef w4...@localnet.com wrote: From: w4sef w4...@localnet.com Subject: [Repeater-Builder] Re: Two questions To: Repeater-Builder@yahoogroups.com Date: Wednesday, May 13, 2009, 3:15 PM OK Jim, THANK YOU for that info! Which pin on the black socket? 73s Steve W4SEF --- In Repeater-Builder@ yahoogroups. com, Jim Brown w5...@... wrote: The first limiter is available on a GE Mastr II on the test socket, and can be used for signal strength after a signal is well above the noise. Lots of signals can be copied full quieting before the first limiter starts to show a reading. On the P S controller, you have to hook up to the CTCSS input on the GE exciter board to get the signal from the controller into the system. Look closely at the instructions from P S to see what connections have to be added. Just plugging the controller in does not get the CTCSS signal to the exciter. 73 - Jim W5ZIT --- On Sat, 5/9/09, w4sef w4...@... wrote: From: w4sef w4...@... Subject: [Repeater-Builder] Two questions To: Repeater-Builder@ yahoogroups. com Date: Saturday, May 9, 2009, 11:40 AM Hi all, I am new at the GE Mastr II gameIs there a point on the receiver board where I can tap off to get an S meter reading? I would like to be able to monitor the signal incoming. Also, be able to see if there is any rise in meter reading with no signal coming in to check for desense with the transmit on and off. I had a Micor and knew where to tap the second limiter for a meter reading on signals but can not find the right place on the Mastr II. Also, I am using the Pion Controller board. I love the controller but I can NOT get it to transmit the CTCSS tone. I have tried every setting I can think of using the computer to program it but no luck. It will DECODE fine but will NOT send the tone! Any ideas? Thanks Steve W4SEF
Re: [Repeater-Builder] Two questions
The first limiter is available on a GE Mastr II on the test socket, and can be used for signal strength after a signal is well above the noise. Lots of signals can be copied full quieting before the first limiter starts to show a reading. On the P S controller, you have to hook up to the CTCSS input on the GE exciter board to get the signal from the controller into the system. Look closely at the instructions from P S to see what connections have to be added. Just plugging the controller in does not get the CTCSS signal to the exciter. 73 - Jim W5ZIT --- On Sat, 5/9/09, w4sef w4...@localnet.com wrote: From: w4sef w4...@localnet.com Subject: [Repeater-Builder] Two questions To: Repeater-Builder@yahoogroups.com Date: Saturday, May 9, 2009, 11:40 AM Hi all, I am new at the GE Mastr II gameIs there a point on the receiver board where I can tap off to get an S meter reading? I would like to be able to monitor the signal incoming. Also, be able to see if there is any rise in meter reading with no signal coming in to check for desense with the transmit on and off. I had a Micor and knew where to tap the second limiter for a meter reading on signals but can not find the right place on the Mastr II. Also, I am using the Pion Controller board. I love the controller but I can NOT get it to transmit the CTCSS tone. I have tried every setting I can think of using the computer to program it but no luck. It will DECODE fine but will NOT send the tone! Any ideas? Thanks Steve W4SEF
Re: [Repeater-Builder] Re: Identify a coax and possible connector vendor
I have successfully used standard 50 Ohm type N connectors on 75 Ohm CATV coax. I purchased some brass tubing from a hobby shop that fit the ID of the center pin of the 50 Ohm connector and sweat soldered a short piece to the copper clad center conductor on the coax. With this modification the normal 50 Ohm connectors fit the 75 Ohm cable and work just fine. 73 - Jim W5ZIT --- On Fri, 5/8/09, N3QAM n3...@comcast.net wrote: From: N3QAM n3...@comcast.net Subject: Re: [Repeater-Builder] Re: Identify a coax and possible connector vendor To: Repeater-Builder@yahoogroups.com Date: Friday, May 8, 2009, 9:45 AM There is a whole write up on the net somewhere on how to use the 75 ohm hardline connectors and covert them to a n conector or pl-259 with pics . If you need any let me know as i am a line tech for a cable company . Unfotunetly it will be hard for me to core the cable for you to install the connectors unless you are close by. If you get to that point , i would suggest going to the local office of your cable company ( not a payment center but one that the line techs and construction department works out of) and ask them if they can core them for you. The connetors installs differently than say a PL-259 would and are either a 2 piece or a 3 piece. The coring tool actually cores out the dialetric and leaves the center conductor exposed with the shield. i do not have any here at the house to take pictures of it , nor be at work for the next month ( due to a back surgery). But feel free to contact me if you have any further questions. Keith N3QAM - Original Message - From: pontotochs To: Repeater-Builder@ yahoogroups. com Sent: Friday, May 08, 2009 10:35 AM Subject: [Repeater-Builder] Re: Identify a coax and possible connector vendor Thanks to N3QAM and Ben. You guys nailed it with the P3 500 from China. I also appreciate Ben's tip on how to use a PL259. Regards, Rick, N5RB --- In Repeater-Builder@ yahoogroups. com, N3QAM n3...@... wrote: like 500 p3 or variant - Original Message - From: N3QAM To: Repeater-Builder@ yahoogroups. com Sent: Thursday, May 07, 2009 8:18 PM Subject: Re: [Repeater-Builder] Identify a coax and possible connector vendor sounds like some 75 ohm cable self support - Original Message - From: pontotochs To: Repeater-Builder@ yahoogroups. com Sent: Thursday, May 07, 2009 8:16 PM Subject: [Repeater-Builder] Identify a coax and possible connector vendor Hi, One of the ham repeater owners in the area has acquired a coax that I can't identify. No markings on the jacket. It has a nominal jacket diameter of 0.58 inches (it looks to be the 'standard' black PE), it has a solid aluminum shield (0.51 OD), about 0.028 thick. The dielectric looks to be the PE foam. The center conductor is copper over aluminum with a 0.11 OD (about #10 gauge). It looks to be 50 ohm based on a rough calculation. The interesting thing about this cable is that it has a messenger wire molded to the outside of the jacket. It is about # 10 gauge steel. It is not wrapped around the coax, just to one side, about 0.2 inches away. When I say molded, I mean that messenger wire and coax have the same black insulator jacket with a rib of the same material between them. I am looking for a source of connectors for this cable, so any help identifying it would be appreciated. Thanks for your help in advance, Rick, N5RB
Re: [Repeater-Builder] Re: W1GAN and square duplexers aka homebrew duplexer
As I recall, an early ARRL VHF manual had a brief chapter on repeaters, and I believe there were two articles that were of interest. One was the duplexer and another was a four bay folded dipole antenna for repeater use. If you know where the four vertical bay antenna article is located, you may find the duplexer article also. I think it also was a QST article. I remember one fellow who built the duplexer complained that when it was hit by lightning, it disassembled itself. He had made the outside tube out of individual sheets of copper soldered together, and the solder joints let go when it took the strike. 73 - Jim W5ZIT --- On Tue, 4/28/09, cruizzer77 atlant...@gmx.ch wrote: From: cruizzer77 atlant...@gmx.ch Subject: [Repeater-Builder] Re: W1GAN and square duplexers aka homebrew duplexer To: Repeater-Builder@yahoogroups.com Date: Tuesday, April 28, 2009, 5:18 AM It's interesting to hear about your projects! I would be interested in knowing which VHF manual you're referring to, Jim.
Re: [Repeater-Builder] Re: W1GAN and square duplexers aka homebrew duplexer
We built a duplexer back in the late '70s using sections cut from the refueling boom from a KC-135 tanker. After cutting the six sections to length, the inside of the top end had to be machined to be able to insert a cap with the center tube and coupling loops inside with a tight fit. The other end of the tubing had a square piece welded to the bottom to close out the tube. The tubing was about six inches in diameter and about a quarter inch thick, as I recall. We used the design in the repeater section of the VHF manual and used two connectors with a cap between the connectors on one side and an inductor between the connectors on the other side. The thing worked as long as the temp was constant, but with varying temperature, it was all over the place in tuning. When we finally got the money together we bought a 4 can 8 inch DB duplexer and it is still in service. 73 - Jim W5ZIT --- On Sun, 4/26/09, cruizzer77 atlant...@gmx.ch wrote: From: cruizzer77 atlant...@gmx.ch Subject: [Repeater-Builder] Re: W1GAN and square duplexers aka homebrew duplexer To: Repeater-Builder@yahoogroups.com Date: Sunday, April 26, 2009, 3:03 PM Since your post I've been googling like hell and found one Dutch design of a copper clad duplexer by PA0NHC, but this also has two loops per cavity and uses 8 cavities. However it answers the question about square enclosures and could be a reference design. Furthermore I found a design by WB3AYW which uses 16 gallon transmission fluid barrels as cavities in BPBR configuration using 4 cavities. This one looks easy to build and is somewhat similar to the beer keg duplexer which has been made professionally in the seventies afaik. The problem with these is that a 4 cavity duplexer gets pretty big and will hardly fit into a 19 cabinet. Does anyone know of any other particular homebrew design, especially one which uses some kind of available enclosure similar to the barrels but more space-saving? I also found some notice that the heliax duplexer, which is well-known for 6 meters, could also be built for 2 meters, but no detailed info was given. If anyone knows more about this, please tell... --- In Repeater-Builder@ yahoogroups. com, DCFluX dcf...@... wrote: There were a couple of designs that used copper circuit boards to form square boxes for the outer jacket of the duplexer. Size maters as the inner to outer diameter ratio effects the impedance of the cavity. It is my understanding that the optimum impedance for a cavity is approx 70 ohms. Not sure if this is true for cavities, but with helical resonators square shields have higher Q than round ones. You would also probably be better off using a BpBr style design, as I remember W1GANs was for pass cavities which would require 6, BpBr can get away with use 4, they would be similar but only have 1 coupling loop that has a high quality trimmer capacitor such as a johansen or a coaxial gimmic in the ground leg of the loop to set the notch frequency. On Fri, Apr 24, 2009 at 4:19 AM, cruizzer77 atlant...@. .. wrote: Hi Most of you who are into duplexers will know W1GAN's old QST-article A Homemade Duplexer for 2-Meter Repeaters. His design uses 4 copper tubes, but today many duplexer manufacturers use square aluminium profile as duplexer bodies, i.e. Sinclair but others as well. Now I wondered if W1GAN's design could be used for building such an aluminium square tube duplexer as well and if it would work equally well. Does anybody know? Instead of the 4 round tube, would a 4 square tube be used, or does the circumference matter? Kind regards Martin - - -- Yahoo! Groups Links __
Re: [Repeater-Builder] cat1000 controller and alinco dr235t remote issue
The COR on the Alinco radios is an open collector that goes to ground when a signal is received. These radios can be configured as back-to-back crossband repeaters by simply connecting the interface of one radio to the interface of the other radio. If you can configure the CAT 1000 for a negative going COR input you may only need to add a pull up resistor to the COR output of the Alinco radio to get it to transition. If the CAT 1000 requires a positive transition for COR input, you will need to add a transistor inverter in addition to the pullup resistor. 10K would be a good value to use as the pullup with one end connected to the COR output of the radio and the other end connected to + 12 VDC. If you need any help with the inverter, let me know. 73 - Jim W5ZIT --- On Wed, 3/25/09, Joe Landers ke4...@ke4eue.org wrote: From: Joe Landers ke4...@ke4eue.org Subject: [Repeater-Builder] cat1000 controller and alinco dr235t remote issue To: Repeater-Builder@yahoogroups.com Date: Wednesday, March 25, 2009, 8:25 PM I was wondering if anyone in the group has ever used a alinco 135/235/435 radio as a remote base with a cat 1000 controller. I have a issue with this setup not broadcasting what the remote receives. The radio broadcast what the repeater sends but does not go the other way. I am using the 9 pin connector on the radio. Thanks Joe Landers Ke4eue
Re: [Repeater-Builder] Re: simplex repeater
I saw this work once back in the '70s when the Ft Worth TX 146.94 repeater was configured to retransmit the 146.94 output of the Little Rock AR repeater. This was possible because the Ft Worth repeater receiver was at 1000 ft with its transmitter at 500 ft. 440 Links back to the control operator for 146.94 as well as 146.34 allowed him to patch the 94 received signal to the 94 transmitter. The repeater would howl during stand down for the Little Rock repeater, but I carried on a conversation with a station in Little Rock through this lash up. Obviously the band was open for the over 200 mile path between Little Rock and Ft Worth. 73 - Jim W5ZIT --- On Wed, 3/25/09, Laryn Lohman lar...@hotmail.com wrote: From: Laryn Lohman lar...@hotmail.com Subject: [Repeater-Builder] Re: simplex repeater To: Repeater-Builder@yahoogroups.com Date: Wednesday, March 25, 2009, 9:25 PM These setups would simultaneously transmit on the same frequency. Has anyone else seen such application notes or booklets??? Burt VE2BMQ None other than our own Mike WA6ILQ co-wrote a book on repeaters a number of years ago and referenced with an illustration and text how such a repeater would work. Would be fun to play with sometime... Still good reading by the way. Laryn K8TVZ ___
Re: [Repeater-Builder] Thank You - Interference Help - WTB
In the early '70s I coordinated a repeater in Texas(146.985) between a 146.97 repeater in Dallas and a 147.70 repeater near Sherman. One was 50 miles and the other about 40 miles away. My coordination required that I not have any complaint from either already established repeater to continue my operation. I operated this repeater for quite a few years before Texas shifted to a 20 kHz spacing plan, when I was assigned a 147.16 frequency. I never had any complaint while using a Spectrum transmitter and receiver which I had assembled on a chassis with a homebrew controller. I am sure that many of the CA repeaters using this band plan operate without any problems, so it is a workable band plan, proved many times. 73 - Jim W5ZIT --- On Wed, 3/25/09, n...@no6b.com n...@no6b.com wrote: From: n...@no6b.com n...@no6b.com Subject: Re: [Repeater-Builder] Thank You - Interference Help - WTB To: Repeater-Builder@yahoogroups.com Date: Wednesday, March 25, 2009, 9:54 PM At 3/25/2009 15:35, you wrote: Back in the day, a channel was 30 kHz wide. When they were split to meet demand, California was not the only coordination jurisdiction which chose to put the half channels upside down. From what I gather from the old-timers, it was easier to protect your input from a single, consistent signal, (the other repeater's output,) 15 kHz off your input but far away, than it was to deal with an ever-changing pool of users who could be right under your site, trying to work the distant repeater with high power and frequency tolerance inferior to the distant repeater. Precisely, Paul. Glad to see others have figured out the reasoning behind our oft-trashed bandplan. The best part is that with a little extra planning spec'ing, 60 or even 40 mile separation isn't necessarily required to make it work, although you've got to use good equipment - no 30 kHz channel-spec' d radios without modifications. California had to be first in finding solutions to many band-crowding issues. Maybe hams there will be the first to narrow-band? Our 4 D-Star pairs are spacing @ 10 kHz; no interference complaints so far. Bob NO6B
RE: [Repeater-Builder] Thank You - Interference Help - WTB
Actually the Texas band plan was like theirs, my output was on 146.385 with an input on 146.985 between the 146.97 and 147.00 outputs. Texas did not keep it for long though, before converting everyone to 20 kHz spacing instead of the original 30 kHz with the splinters 15 kHz away but upside down to the original 30 kHz band plan. Sorry I was not clear on my post as to where my output was located. It seemed to work OK as far as I could tell. 73 - Jim W5ZIT --- On Thu, 3/26/09, Nate Duehr n...@natetech.com wrote: From: Nate Duehr n...@natetech.com Subject: RE: [Repeater-Builder] Thank You - Interference Help - WTB To: Repeater-Builder@yahoogroups.com Date: Thursday, March 26, 2009, 5:18 PM Jim, your example does not have the inputs on top of the outputs. You have outputs side by side 15 kHz apart. That’s common in a lot of places (including Colorado here). They’re talking about inputs 15 KHz away from outputs. That’s a tad more difficult. .
Re: [Repeater-Builder] Master II station 66 split conversion to 56 split
I have retuned 10+ GE Mastr II exciters - base/moble and have never had to change a component. Put the ICOM in for the new frequency and tune per the manual. I use a Bird milliWatt meter that has a 250 mW full scale and an internal 50 Ohm load to finish the tuning, after going through the test points with a Simpson 260. Peaking the previous stage and dipping for the input to the next stage as per the tuning instructions will give you a working exciter as long as there is no component issue in the exciter. 73 - Jim W5ZIT --- On Sun, 3/22/09, Morris Dillingham mdi...@nnwifi.com wrote: From: Morris Dillingham mdi...@nnwifi.com Subject: [Repeater-Builder] Master II station 66 split conversion to 56 split To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 2:20 PM Now that you have helped me close out the old Spectrum issues, can anyone point me to the list of caps and their new values to convert the exciter board of a Master II station? On the NHRC site I see mention of the need to change out a dozen or so caps but no other references. 73 de Morris KI4IUA
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
I have done the mod mentioned on several DB-224 antennas by taking some six inch lengths of an old TV antenna and flattening about three inches on one end and wrapping the flattened end around the end of the dipole and putting a machine screw through the flats to hold the extension to the dipole. I then cut the extension back to two inches. This has resulted in a lower SWR in the ham band after moving the 155 mHz antennas down. I have made no changes to the harness to move the antenna. Something like a change from 1.8:1 down to 1.2:1 is what I have measured at the antenna. 73 - Jim W5ZIT --- On Sun, 3/22/09, Tom, N6MVT n6...@comcast.net wrote: From: Tom, N6MVT n6...@comcast.net Subject: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 4:09 PM Also, I have seen some of the dipoles get modified with short stainless machine screws+nuts drilled through the top bottom of the dipole elements, to help get the Return Loss even better at lower freqs. Not sure what, if any, skewed pattern is introduced by doing the machine screw mod or not. Quite often it's hard to tell any changes in the field unless it is very drastic. Tom
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
I had a buddy who did physically lengthen the two ends of each dipole by cutting them and inserting aluminum tubing and welding the assembly back together. His brother in law was good at aluminum welding. Again, he did not change anything in the harness and the antennas work fine now in the ham band. 73 - Jim W5ZIT --- On Sun, 3/22/09, Chuck Kelsey wb2...@roadrunner.com wrote: From: Chuck Kelsey wb2...@roadrunner.com Subject: Re: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 5:30 PM A better method might be to actually cut each half of the element at about the mid-point (not at the bend - at the straight section), then slide some smaller tubing inside. Slide the element ends in and out while testing and then use some stainless screws to attach things back together at your new length. I suppose you could also measure the length of the extension and cut that length from a piece of tubing that is the same size as the original element. This would effectively hide your repair and keep the element the same diameter for the entire length. Chuck WB2EDV - Original Message - From: Jim Brown To: Repeater-Builder@ yahoogroups. com Sent: Sunday, March 22, 2009 6:13 PM Subject: Re: [Repeater-Builder] Re: Decibel dipole array sweeps I have done the mod mentioned on several DB-224 antennas by taking some six inch lengths of an old TV antenna and flattening about three inches on one end and wrapping the flattened end around the end of the dipole and putting a machine screw through the flats to hold the extension to the dipole. I then cut the extension back to two inches. This has resulted in a lower SWR in the ham band after moving the 155 mHz antennas down. I have made no changes to the harness to move the antenna. Something like a change from 1.8:1 down to 1.2:1 is what I have measured at the antenna. 73 - Jim W5ZIT --- On Sun, 3/22/09, Tom, N6MVT n6...@comcast. net wrote: From: Tom, N6MVT n6...@comcast. net Subject: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@ yahoogroups. com Date: Sunday, March 22, 2009, 4:09 PM Also, I have seen some of the dipoles get modified with short stainless machine screws+nuts drilled through the top bottom of the dipole elements, to help get the Return Loss even better at lower freqs. Not sure what, if any, skewed pattern is introduced by doing the machine screw mod or not. Quite often it's hard to tell any changes in the field unless it is very drastic. Tom
Re: [Repeater-Builder] Master II station 66 split conversion to 56 split
Hey - I thought we were talking about the standard osc/multiplier exciters for VHF. The only thing I have ever had to do to move a PLL exciter down into the ham band is replace the aluminum slug in the PLL coil with a ferrite slug. My installs are non temperature controlled and the temps range from -10 to about 100 deg F. No problems with maintaining a lock over that range, but the exciter was optimized at room temp for the correct lock voltage on only one frequency. The applications have all been repeaters with no frequency switching. I understand that some component values are changed for a factory change in frequency from commercial frequencies down into the ham band, but I have not had to make any changes other than the slug change when converting a 66 range PLL exciter. 73 - Jim W5ZIT --- On Sun, 3/22/09, Kris Kirby k...@catonic.us wrote: From: Kris Kirby k...@catonic.us Subject: Re: [Repeater-Builder] Master II station 66 split conversion to 56 split To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 5:40 PM On Sun, 22 Mar 2009 n...@no6b.com wrote: I have retuned 10+ GE Mastr II exciters - base/moble and have never had to change a component. Put the ICOM in for the new frequency and tune per the manual. Same experience here, except that if you want to put one on the 144.390 APRS frequency you may find that some exciters don't quite make it down that far. What sort of temperature coeffiecent does the exciter have? If I want to find the limits of lock, do I need to freeze it or heat it up to 140 degrees? -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
I manage to clamp the addition to the element pretty tight with the machine screw and nut through a hole drilled through both sides of the flattened part of the addition wrapped around the element. And since only aluminum touches the aluminum element, I don't see any dissimilar metal problems in the conduction part of the element. Sure enough, the stainless screws that clamp the extensions are not aluminum, but they do not conduct any current to speak of at the hot ends of the dipoles. The oldest one that I have modified was just taken down in favor of a new DB-224E. The old dipoles and harness were 30 plus years old, and the wood phone pole the antenna was on broke off and fell five years ago. That is when the extensions were added, along with a new aluminum mast. We did see some improvement in coverage when the antenna was replaced, but we never had any noise or desense that I could attribute to the old antenna. I have modified several antennas this way, and have been pleased with the way they work after the mod. A buddy in Florida modified one and it is in operation on their repeater in a much more humid environment and he has not reported any antenna problems to me. So I can recommend this simple mod to get a better SWR for the duplexer to look into, for what that is worth. I used unmodified antennas for lots of years and just used what they showed for SWR and tuned the duplexer to give a good SWR to the transmitter. But I like being able to tune up the duplexer on the bench using 50 ohm loads and pads and not having to do any field tuning because of a mis-matched antenna. This mod may not be suitable for some sites I am sure, but has worked well for me so far. 73 - Jim W5ZIT --- On Sun, 3/22/09, Nate Duehr n...@natetech.com wrote: From: Nate Duehr n...@natetech.com Subject: Re: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 5:47 PM On Mar 22, 2009, at 4:13 PM, Jim Brown wrote: I have done the mod mentioned on several DB-224 antennas by taking some six inch lengths of an old TV antenna and flattening about three inches on one end and wrapping the flattened end around the end of the dipole and putting a machine screw through the flats to hold the extension to the dipole. I then cut the extension back to two inches. I like the ingenuity Jim, but isn't that just begging for dissimilar metal contact noise down the road after a few years of grime, corrosion, and weathering? I'd want to see how those antennas performed after 3-5 years and whether or not site noise was seeming to wander up, or others on-site were complaining of new mixes hitting receivers, etc. One of those things coming loose and scraping back and forth as the add-on extension swung in high winds, would probably make a hell of a crackling noise on the machine connected to it, too -- wouldn't it? Joints that can move, even only after some kind of damage, to me anyway = lots of trouble down the road. -- Nate Duehr, WY0X n...@natetech. com
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
We made one back in the '70s from 3/4 inch aluminum angle. We sawed a vee at each bend point and welded the bent angle back together and made a very stable element. The dimensions we used were from an old VHF handbook and the elements were spaced quite a bit farther from the mast than a DB-224. Our matching harness never did work out right for that antenna and it was never put in service, but mechanically it seemed to be pretty sturdy. 73 - Jim W5ZIT --- On Sun, 3/22/09, Kris Kirby k...@catonic.us wrote: From: Kris Kirby k...@catonic.us Subject: Re: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 6:01 PM On Sun, 22 Mar 2009, rahwayflynn wrote: I have access to 316 stainless tube am willing to take a shot at fabricating replacement elements. Sounds like fun. I think the DB antennas are made from aluminum, however. If you're going to be making a DB antenna clone, it makes more sense to either punch them out of plate or cut them from rod. Any mechanical engineers on the list? :-) -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
The dimensions are in the FILES here on the Repeater-Builder list. http://f1.grp.yahoofs.com/v1/MPvGSaXwn7VidapqNO9aJxssOWkx7N4yimg7VCgz9rDCxTSilYgmOPHi-yTakY_HTGB5tEDhwoOUFpePfhgiw9oi/db-224e-diagram-dz.pdf With the luck everyone had with Jeff's link, this one will probably not work. But look in the FILES section of the site at Yahoo to find the docs. 73 - Jim W5ZIT --- On Sun, 3/22/09, rahwayflynn mafl...@att.net wrote: From: rahwayflynn mafl...@att.net Subject: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 5:53 PM --- In Repeater-Builder@ yahoogroups. com, Kris Kirby k...@... wrote: The results, I would say in practical terms, is that a DB-224 cut for 165MHz isn't a bad thing. You'll experience some uptilt. But matching the antenna to a 50-ohm transmitter is another issue altogether. So the question is, does anyone have an out-of-service DB-224 (hopefully on the ground) that was custom built for amateur service that dimensions can be lifted from from? I have access to 316 stainless tube am willing to take a shot at fabricating replacement elements. Martin
Re: [Repeater-Builder] Re: Decibel dipole array sweeps
I had to copy the link and paste it into the browser and then go back through and take out all the spaces that Yahoo added, but with that done I got back to the doc OK. 73 - Jim W5ZIT --- On Sun, 3/22/09, Jim Brown w5...@yahoo.com wrote: From: Jim Brown w5...@yahoo.com Subject: Re: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@yahoogroups.com Date: Sunday, March 22, 2009, 10:48 PM The dimensions are in the FILES here on the Repeater-Builder list. http://f1.grp. yahoofs.com/ v1/MPvGSaXwn7Vid apqNO9aJxssOWkx7 N4yimg7VCgz9rDCx TSilYgmOPHi- yTakY_HTGB5tEDhw oOUFpePfhgiw9oi/ db-224e-diagram- dz.pdf With the luck everyone had with Jeff's link, this one will probably not work. But look in the FILES section of the site at Yahoo to find the docs. 73 - Jim W5ZIT --- On Sun, 3/22/09, rahwayflynn mafl...@att. net wrote: From: rahwayflynn mafl...@att. net Subject: [Repeater-Builder] Re: Decibel dipole array sweeps To: Repeater-Builder@ yahoogroups. com Date: Sunday, March 22, 2009, 5:53 PM --- In Repeater-Builder@ yahoogroups. com, Kris Kirby k...@... wrote: The results, I would say in practical terms, is that a DB-224 cut for 165MHz isn't a bad thing. You'll experience some uptilt. But matching the antenna to a 50-ohm transmitter is another issue altogether. So the question is, does anyone have an out-of-service DB-224 (hopefully on the ground) that was custom built for amateur service that dimensions can be lifted from from? I have access to 316 stainless tube am willing to take a shot at fabricating replacement elements. Martin
Re: [Repeater-Builder] GE mastr II station PA
I have moved several GE Mastr II 40 watt units up from the 417 mHz area to the 440 mHz area as repeaters. The exciter tunes up OK to the higher frequency, but the receiver front end and LO multiplier will not tune. I use LOW side injection for the LO string and modify the helical resonators in the front end. I remove all the helical resonator coils and remove one quarter turn from each coil to get it to tune up into the 440 band. The modified receiver will tune from 420 through 450 with this mod. A better approach is to obtain a 450-470 mobile and exchange the LO and front end modules. No modification is required to the helical resonators on the 450 to 470 radios. Be sure to use HIGH side injection for the receiver with the 450-470 front end. On the low pass filter for the transmitter, I paralleled a #20 bare wire with the wire already in place coupling the sections of the filter together and the reduced inductance moves the filter up enough into the band to pass 450 with no problem. I did not change anything else in the amp. 73 - Jim W5ZIT --- On Tue, 3/10/09, iamcranked la...@thunderbolt.net wrote: From: iamcranked la...@thunderbolt.net Subject: [Repeater-Builder] GE mastr II station PA To: Repeater-Builder@yahoogroups.com Date: Tuesday, March 10, 2009, 3:55 AM I am looking for some help with a UHF GE Mastr II base I just acquired. I've never worked on one of these before and have no knowledge as to what mods need to be done. My unit currently is on 416.550 and I need to move it up to 444.425 but have some questions before I begin. My biggest concern is about the Power Amp. I have a 19D321347 G5 Rev N PA board which according to LBI-30213E is a 406-420 Mhz 40 watt PA. There seems to be another version of the same board number except it is a G9 and the LBI says it is for 420-450 Mhz but I can't find a listing with the differences between them. The LBI shows both G5 and G9 range boards with the same components listed as the (LL) designation supposedly covering the entire 406-450 range. Can anyone enlighten me as to the difference between the G5 and G9 version of the 40 watt PA?. Will the 406-420 PA board work in the 444 range? If not can anyone advise what mods need to be done so it will? My PA also has a 19D327024 G1 filter which shows it is used in both the 406-420 range as well as 420-450 range. However when the G9 version of the PA board is used it shows it covers 420-450 Mhz. Will I need to mod the filter to get the 444 Mhz signal to pass? There again I find no differences to the filter board when used in the different segments. I appreciate any help Larry - N7FM
Re: [Repeater-Builder] Split site link via IP
In the KISS mode, here is a simple solution that can be used for a trial. At the receiver site, use a PL decoder to gate audio into a SKYPE port on the computer at the receive site. Audio would only be present if the receive signal had the proper tone present. At the transmit site, use a SignalLink USB port on SKYPE to feed audio and PTT (COS) to your controller. Put the controller at the transmit site and feed the SignalLink audio and PTT signals to the controller in place of the normal receive signals. SKYPE does not need a PTT signal to activate the audio into the system. The system is full duplex, and audio from the receive site is active all the time. The PL at the receiver controls the audio input. At the transmit site, the SignalLink recovers the PTT using a VOX circuit with front panel adjustments to supply the COS input to your controller of choice. Use a control receiver at your transmit site to feed control DTMF signals to your controller using a frequency of 220 or above for a legal system. SKYPE does have the usual encode/decode delay, but does not have the UDP routing problem. All signals are TCP/IP in the SKYPE system. 73 - Jim W5ZIT --- On Mon, 3/9/09, Ethercrash n4bwp...@charter.net wrote: From: Ethercrash n4bwp...@charter.net Subject: [Repeater-Builder] Split site link via IP To: Repeater-Builder@yahoogroups.com Date: Monday, March 9, 2009, 9:42 AM My repeater group is considering building split-site 6m machine. As an inter-site link, I was thinking of using some sort of VOIP arrangement via the internet. I'm curious if anyone has tried something like this: My idea is to use a point-to-point, private link (i.e. not IRLP or Echo) to pump audio and maybe even some signaling between sites. The receive site would consist of the receive radio, controller (most likely an Arcom), and a PC to do the encoding/streaming. The transmit site would consist of a PC to decode the audio stream, a PL decoder for TX logic, and the TX radio. The basic premise would be to take audio from the RX (PL filtered), fed thru the controller, mixed with link PL, and fed to the PC's audio input. The PC then streams the audio over the internet to the RX site PC, where it is decoded and fed to the TX radio, which will be keyed by a PL decoder (provided the IP encode/decode process hasn't mangled the PL). Whew... Now, question is: will it work? Or more properly, has anyone made this work? I'm going to try it on a small scale just to prove concept, but I'm curious if anyone has tried this already. My intention is to use something along the lines of Winamp with Shoutcast or Windows Media Encoder to stream the audio. I'd rather find a Linux-based CLI encoder if such an animal exists. I had thought about using IRLP nodes as endpoints, but IRLP policy would preclude that. Thoughts? Encouragement? FTW is he THINKING?!?! ;) I'd be interested in the group's thoughts, and I'll report the results of my experiments. Thanks 73, Brian, N4BWP
Re: [Repeater-Builder] 900 MHz WISP on repeater tower?
I have a remote receiver site at a 900 mHz distribution point where the 2.4 gHz baseband is distributed down on 900 mHz and the noise is really bad. I can't copy my repeater to test the remote receiver till I walk about 200 ft from the tower where the 900 mHz stuff is located. I have a GE Mastr II remote receiver with the squelch set as tight as it will go to squelch out the digital noise. During the squelch tail before the PL squelch closes it sounds just like a packet station in the receiver. We are looking for another site for that remote, as the site with the 900 mHz stuff is unusable. 73 - Jim W5ZIT --- On Wed, 1/21/09, Paul N1BUG paul_n1...@verizon.net wrote: From: Paul N1BUG paul_n1...@verizon.net Subject: [Repeater-Builder] 900 MHz WISP on repeater tower? To: Repeater-Builder@yahoogroups.com Date: Wednesday, January 21, 2009, 3:34 PM I could use a little help here. I have a repeater tower with 2 meter and 440 repeater on it. I have been contacted by a wireless internet service provider about putting some 900 MHz stuff on my tower. The deal they are offering is attractive but I'm wondering if there would be interference issues between their stuff and my repeaters. I'm going to be setting up a meeting to discuss technical aspects of the proposed system, but I have no experience or knowledge in this area and am not sure what questions I should be asking them. Any suggestions or advice? Thanks! Paul N1BUG
Re: [Repeater-Builder] Coax Interconnect (Inside Repeater)
The rule of thumb we used on the military aircraft RF cabling was that when we were using a larger sized cable like RG-214 we always used a type N, while if we were using a smaller cable like RG-142 we used a BNC. I worked on reconnaissance aircraft for the Air Force and Navy. For video cabling we always used BNC and the wideband tape recorders were always delivered with BNC connectors. 73 - Jim W5ZIT --- On Wed, 1/21/09, Mike Pugh mikep...@mikepugh.net wrote: From: Mike Pugh mikep...@mikepugh.net Subject: Re: [Repeater-Builder] Coax Interconnect (Inside Repeater) To: Repeater-Builder@yahoogroups.com Date: Wednesday, January 21, 2009, 2:55 PM Alexander N Tubonjic wrote: I am wanting to swap out the BNC receiver connector to an N connector on my Kenwood TKR-750 2 meter repeater. After contacting Kenwood and getting quoted some crack prices I figured I'd see if anyone has anything laying around or has any ideas on here. Why? electrically, the BNC connectors and the N connectors are the same thing. Don't believe me? Try plugging them together.. Even though they won't latch together, electrically, they fit together perfectly, and can be used this way in an emergency if you're at a tower site and find you don't have the proper connector.. What am I missing? Mike
Re: [Repeater-Builder] OT Off Topic
I bought an IBM 390 laptop on eBay for $9.95 that was advertised without a hard drive. The vendor responded to a question that I asked about booting to DOS from a floppy and he indicated that it would. It has an EPP capable parallel port as well as a standard 9 pin serial port and I use the parallel port to program EEPROMs as well as EPROMs with external programmers. The serial port works great to program my Zetron (special serial cable) and Pion and Simon and ID-O-Matic controllers. Taking a desktop to a site was not an option for me, and I have found the old IBM (233 mHz) to be the simple answer for remote computer tasks. 73 - Jim W5ZIT --- On Sun, 1/18/09, kh6...@netscape.net kh6...@netscape.net wrote: From: kh6...@netscape.net kh6...@netscape.net Subject: Re: [Repeater-Builder] Off Topic To: Repeater-Builder@yahoogroups.com Date: Sunday, January 18, 2009, 12:17 AM Thanks for this Off Topic. In the days of 386's, 486's, etc. desktops notebooks had RS-232c ports. What can be done with the XP notebooks, like mine, with no Db-9, RS-232c ports, all that is available is USB ports? I am hoping to get an old dest top with Db-9, RS-232c working with my old Windows 3.1 software. This will mean taking this desk top to the repeater site, to program the repeater controller. I have a USB to Db-9, RS-232c adapter w/ a cd software. If I could get a Windows AT program to work with XP. I await your solutions. 73's Thanks. Jim Kh6jkg. -Original Message- From: AJ aj.grantham@ gmail.com To: Repeater-Builder@ yahoogroups. com Sent: Sat, 17 Jan 2009 6:32 pm Subject: Re: [Repeater-Builder] Off Topic However... As the previous replies have stated, while you may be able to open and run the DOS application in XP, you won't be able to do anything with regards to controlling external devices via serial, such as a radio in the case of RSS... XP has some rather nasty issues with typing the serial ports for Windows-only applications. .. 73s and good luck, AJ, K6LOR On Sat, Jan 17, 2009 at 9:30 PM, Ken Arck ah...@ah6le. net wrote: At 07:59 PM 1/17/2009, Mike Mullarkey wrote: Does anybody know if one can get a DOS program to run on Windows XP. If it's a RSS program, it won't run inside a DOS window from XP and you need to boot into DOS at powerup (make a bootable CD to do this). Otherwise if the program you want to run WILL run inside a DOS window from within XP, just click START RUN and at the C:/ prompt, do what you need. Ken - - - - - - - --- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcon trollers. com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp. net We don't just make 'em. We use 'em! A Good Credit Score is 700 or Above. See yours in just 2 easy steps!
Re: [Repeater-Builder] Running or Booting Dos Radio Programs in - with Windows 98se
I have posted this info on this list before, but for those who missed it: Windows 98 has a very usable version of DOS supplied. The only trick is to boot to the DOS system without ever getting to Windows. To do this simply add a PAUSE statement as the last line in the autoexec.bat file. When the boot process gets to this point you will get a message asking if you want to continue and you answer with a CTRL-C. This stops the execution of the batch file and leaves you in DOS. You can add a comment ahead of the PAUSE statement to remind yourself that you can exit to DOS at this point. This version of DOS gives you full access to your hard drive, and has been able to run all the DOS programs I have come across to program EEPROMS and EPROMS. I boot to Windows and use Hyperterm as a terminal program to access the RS-232 port and configure a controller. With a hard drive and Windows XP you will have to boot from a floppy or a CD. You may not be able to access the hard drive from this configuration. 73 - Jim W5ZIT --- On Sun, 1/18/09, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] Running or Booting Dos Radio Programs in - with Windows 98se To: Repeater-Builder@yahoogroups.com Date: Sunday, January 18, 2009, 12:54 PM Hi Mark, I have not found a Dos - Radio Programming Program that I haven't been able to run in/on my vintage Digital HiNote VP Laptop. And I've tried similar setups many other laptops... The only operational quirk is that a few (mostly Motorola RSS/MSS) programs require you exit Windows 98se to MS Dos. And the really ancient programs would like you to slow the world (computer) down to a crawl using the Moslow program. Otherwise many/most of the original Dos Programs operate in Windows 98se using/within a Dos Window. What you probably need right now is... A copy of the original Windows 98 (install) boot disk that tests for and loads a number of on floppy disk available CD Rom Drivers. Rare is/was the case where the mentioned disk failed to boot a usable CD rom driver. The disk boot process delivers you to a prompt of install Windows from a CD or boot to a prompt with or without a CD Rom Driver in place. From that point your machine is now booted to a usable command prompt and depending on your selection with or without a CD Rom Driver. How you deal with loading a program from a CD Rom, Hard or floppy disk from the above mentioned command prompt is another whole thread (I don't have time to type in those steps). So you need to find/obtain a copy of the mentioned Windows 98se floppy disk (and there are at least two versions). Time to learn about the programs rawread (raw-read) and rawwrite (raw-write) which allow you to capture an restore exact floppy disk images. The original programs of course required you run them on/at a dos command prompt... so that might be a fly in your soup if you didn't have the new raw-write program for Windows (mentioned below). With a copy of a Windows 98se boot floppy disk image file you can restore/make your own boot disk and boot to the command prompt as directed above. Raw read and raw write are modestly powerful programs so warnings go out to casual users who don't tend to read directions. A quick search of the net found a windows version... Lucky you. Until I did the search today I had been working with the original dos only version... http://www.chrysoco me.net/rawwrite So in theory... after learning about, finding and installing a raw write type program you can roll your own' (make) Windows 98se boot disk... you just need the disk file image from someone really nice. You might contact that person via Email and see what you receive back. cheers, skipp skipp025 at yahoo.com [pasted text] What is a disk image : A disk image is a file that contains all the raw data on a disk in the original track and sector format. Using a disk image enables you to send diskettes that are not MS-DOS format via FTP or EMail and then recreate them in their original format and integrity. [end pasted text] Mark n9...@... wrote: Nope - this is an OLD machine. No USB, no SCSI. What I am really needing to find are the DOS/Win95 device drivers for the CD drive. It's an NEC Versa 4080h. Just so we can keep this sorta on topic, the primary purpose for this laptop is to run old Motorola and other radio programming software. Mark - N9WYS ._,___
Re: [Repeater-Builder] Lunch Box Radio
I have recently moved a GE Mastr Exec II radio from the 47 mHz area up into six meters. (The MVP and the Exec use the same exciter). I'll admit that the exciter is hard to tune, but it will work without any modification. My technique is to set the frequency of a receiver to each multiplier frequency and place a probe near the stage while tuning. With a peak in signal strength, the stage can then be tuned with a meter on the test point. I built a probe that I use with a one inch piece of insulated wire extending from the end that I can insert into the exciter near the stage I am trying to tune. This same probe works to insert a signal generator output into the individual stages of the front end of the receiver. Tune the mixer first and then work toward the input one stage at a time. 73 - Jim W5ZIT --- On Fri, 1/16/09, Radio Guy ve3...@gmail.com wrote: From: Radio Guy ve3...@gmail.com Subject: Re: [Repeater-Builder] Lunch Box Radio To: Repeater-Builder@yahoogroups.com Date: Friday, January 16, 2009, 2:11 PM Yes, that is something that has been mentioned many times, this could be a waste of time and money, but so far I have lots of people that want to help. It could be a fun project, it is old enough to look like a tube radio, or in this case, a tube radio without tubes! Speaking of trying to get a radio converted to 6m, a GE guy is having problems with a GE MVP, has anyone been successful getting a radio to cover 52.450 and 53.450? Seems it will not tune to 53.450 Tx. And yes I do own a Ranger 6m radio, but do not like the audio on FM. On Fri, Jan 16, 2009 at 1:51 PM, Milt men...@pa.net wrote: Actually, one other item to consider; make sure that the radio is in the highest bandsplit for a conversion to 6meters. Otherwise it will be a painful attempt to convert. It's been too long to remember if there were just 3 bandsplits or more. Milt N3LTQ -- - - - Ken
Re: [Repeater-Builder] Bandpass Filter Board 19B226748G1 Needed for GE PLL Exciter
I have two PLL exciters in service that were moved from the 170 mHz range down into the ham band by only replacing the aluminum slug in the coil with a ferrite slug. One repeater operates at 145.45 mHz and one is at 146.92 mHz. I have seen no degradation due to operating the bandpass filters below the specified range. Normal lock voltage was obtained and the units have operated from ambient 90 deg down to 0 deg with no problems. I did see a reduction in desense when I replaced the multiplier type exciters with the PLL exciters. 73 - Jim W5ZIT --- On Thu, 1/15/09, Larry la...@thunderbolt.net wrote: From: Larry la...@thunderbolt.net Subject: [Repeater-Builder] Bandpass Filter Board 19B226748G1 Needed for GE PLL Exciter To: Repeater-Builder@yahoogroups.com Date: Thursday, January 15, 2009, 2:37 AM Hello group, I'm moving a Mastr ll to down to 146 MHz range for Ham use. I'm in need of a 19B226748G1 (138-155 MHz) bandpass filter board for a GE PLL exciter. The filter currently installed is a 19B226748G2 which shows it's for the (148-174 MHz) range. Would anyone on the list have a 19B226748G1 board they would sell or swap for my G2 version. I am aware that the caps and inductor could be replaced to lower the range but prefer a replacement if someone has one. Please email me off list -- la...@n7fm.com Larry - N7FM ._,___
Re: [Repeater-Builder] Ramsey Preamplifier Kits...
I have three of these preamps in service on GE Mastr II 440 repeaters. The tuned circuit in front of the transistor will help a bit with out of band signals. I build a shield from galvanized flashing and put it around the two turn front end coil. I use these preamps installed in the normal spot for the stock GE preamp, and I was concerned about hanging the front end coil out in the breeze in a repeater. Gain is typically 16 to 20 dB and noise figure is 1 dB @ 2 Meters, 1.2 dB @ 220MHz, and 1.4 dB @ 440 MHz. Which is about what we would expect although the gain value appears a bit optimistic. But who knows... measuring one will tell the real story. I had too much gain on two of my installs and I reduce the gain by placing a 47 Ohm 1/4 watt resistor across the untuned output. I have had no instability from these preamps, even operated wide open for gain. If there is another 440 system in the area though, they are prone to overload and if you have any desense in a repeater, the receiver sensitivity actually will go down with the preamp installation. I have tried the two meter version in a GE Mastr II repeater and was not able to tame the desense increase, although the 440 preamps work fine. The two meter version already has a shielded coil on the front end, by the way. 73 - Jim W5ZIT --- On Sun, 1/11/09, skipp025 skipp...@yahoo.com wrote: From: skipp025 skipp...@yahoo.com Subject: [Repeater-Builder] Ramsey Preamplifier Kits... To: Repeater-Builder@yahoogroups.com Date: Sunday, January 11, 2009, 12:36 PM re: Ramsey Rx Preamplifier Kits. Kevin Custer kug...@... wrote: Great for sites that don't require pre-selection ahead of the preamp. Kevin http://www.ramseyel ectronics. com/cgi-bin/ commerce. exe?preadd= actionkey= PR-SERIES Excellente' lead... Couldn't ask for a more practical low cost kit of this type. The advertisement spouts a little smoke and mirrors but the circuit is pretty straight forward. You can also download the manual before you buy it to have a look at the circuit. The tuned circuit in front of the transistor will help a bit with out of band signals. [pasted ad text] Fully protected against overload and designed for low current and stable operation they employ high Q tuned circuits which restrict out-of-band signals which can cause intermod blanking and over load of your radio's front-end. I doubt the fully protected against overload claim. (Please review the no free lunch rule) The single stage tuned circuit is very nice... but shouldn't be trusted as any type of cure all. Nor is it really comparable against the GLB multi-stage tuned preamp with much higher circuit Q. Don't be misled by GaAs FET claims! The cheap dual-gate FETs (manufactured for TV tuner usage!) used by others just don't come close to the performance of these preamps designed with NEC microwave transistor devices. Smoke... mirrors... pay no attention to the man behind the curtain. Gain is typically 16 to 20 dB and noise figure is 1 dB @ 2 Meters, 1.2 dB @ 220MHz, and 1.4 dB @ 440 MHz. Which is about what we would expect although the gain value appears a bit optimistic. But who knows... measuring one will tell the real story. $14.95 Pretty much says it all if you want a low cost preamp kit. cheers, s. _._,___
Re: [Repeater-Builder] OT- Digital TV converter box issues
My application for a converter box coupon was rejected saying that there were no more coupons available. 73 - Jim W5ZIT --- On Mon, 1/5/09, TRACOMM trac...@yahoo.com wrote: From: TRACOMM trac...@yahoo.com Subject: [Repeater-Builder] OT- Digital TV converter box issues To: Repeater-Builder@yahoogroups.com Date: Monday, January 5, 2009, 2:21 PM Having issues converting over to digital TV. My father volunteered my services to a few of his friends, all serious seniors, Detroit market, As an elecronic wizard (my dad's words) I should be able to make anything with wires work well. Most converter boxes I tried took forever to scan, channels missing, analog TV worked great. Most of the seniors already had their free box, obtained with the converter box coupon. Only boxes I have found so far that seem to work very well are the DigitalStream Zenith pass thru boxes, scan quickly, best picture on rabbit ears. Cost more, but worth the price. Below is a message from another user group, also detailing the frustration in switching over to digital. CJD --- In l...@yahoogroups. com, BB beazer...@. .. wrote: I went out to the home of an elderly couple having problem hooking up their converter boxes. When I arrived, the man had set up the boxes correctly. His problem - he was missing half of the stations he had before! I ran the scan about 10 times. Each time it found different stations. But very few of the UHF channels from Phx. According to www.antennaweb. org - he should be able to get them all - plus some of the Tucson stations. He's getting the Tucson ones that are 70 miles away, but not the Phoenix ones that are 30 miles away. He's using an indoor set top antenna, the kind with the built in amplifier. We tried different settings without much change. Weather conditions at the time - rain. I've noticed at my house when it rains, some channels have severe pixelation. With the converter turned off, he gets all the Phoenix stations analog signals just fine on that indoor antenna. But going through the converter, he's missing a few of the incidental ones...ABC, UPN...ION. Needless to say, he isn't too happy. It looks like unless we can come up with a better option - he needs to call DISH. If Congress wants to talk to an average consumer about what they think of digital television - he'd give them an earful! Any ideas? Bea Lueck
Re: [Repeater-Builder] motorola repeater cable problem
I hooked a pair of GM-300s together for a friend who bought a cable off the internet, and it worked just fine. All I had to do was set the level for deviation with the pot mounted on the board that also mounts the radio connector. The cable he got would cross-band repeat, meaning that it would transmit and receive on both radios, taking audio and key from one radio to key the other. All I had to do was have one radio programmed for the repeater input frequency and leave off the transmit frequency. The other radio was programmed for both transmit and receive. The receive frequency for the second radio was programmed to an unused frequency. The first radio gives a couple of beeps when you turn it on indicating an error in the programming (probably since the transmit frequency is not properly programmed). The repeater functions just fine this way. The cable does not provide for any squelch tail delay, but other than that - it sounds like a normal repeater. 73 - Jim W5ZIT --- On Tue, 1/6/09, dan d dwd71...@yahoo.com wrote: From: dan d dwd71...@yahoo.com Subject: [Repeater-Builder] motorola repeater cable problem To: Repeater-Builder@yahoogroups.com Date: Tuesday, January 6, 2009, 8:30 AM I have two Motorola sm50 mobiles using a repeater cable that goes between the two at the option plug in the back. I have tried every configuration two get this to work with no results. Before I condem the cable I got off ebay does anyone know of any mods or settings that need to be done to get this simplex repeater up and running. I have confirmed the radio operation itself and they are good to go.
Re: [Repeater-Builder] Transmitter fingerprinting?
K3RFI - the ARRL power line noise guru - visited my shack three different times and showed me how he fingerprints power line noise sources. When you have arcs from metal parts not directly in contact, the arc starts and quenches several times for each positive and negative peak on the power line. Counting the number of pulses for each source on a scope hooked to an AM detector at the frequency of interest will give the fingerprint for that noise source. Taking this fingerprint to a suspect pole and tuning a receiver to the 150 mHz area to a quiet channel will allow pinpointing the exact location of the hardware arc. The noise can then be investigated using an ultra-sound detector mounted to the end of a hollow fiberglass pole with the detector on the top end and a speaker coupled to the hollow pole. The audio down converter will take a 50 kHz noise source down to the audio frequencies. The 50 kHz detector is sensitive enough for you to rub your fingers together with the input pointed at your fingers from across a room and hear the swish-swish of your fingers rubbing. I have seen this detector used to find numerous bad insulators and when replaced you would find carbon trails down the sides of the insulators where arcs had been supported. In my HF noise case, it was determined that I had in excess of 30 noise sources and the advice I got from K3RFI and the ARRL was to just move to a different location. This was after the FCC had notified the power company to eliminate the noise generated by the power line. 73 - Jim W5ZIT --- On Wed, 1/7/09, w1ik w...@arrl.net wrote: From: w1ik w...@arrl.net Subject: [Repeater-Builder] Transmitter fingerprinting? To: Repeater-Builder@yahoogroups.com Date: Wednesday, January 7, 2009, 3:57 PM I searched the archives, and did not see this issue addressed. Please forgive me if this has been covered before. Is there anyone here utilizing any form of transmitter fingerprinting software and/or hardware to identify sources of interference, either intentional or otherwise? Can you please provide me with an explanation of just how you are accomplishing this? Your experience and expertise would be greatly appreciated! Thank you! 73 William J. (Jim) Wickstrom, W1IK/NNN0AHC Technical Director, Utica/Shelby Emergency Communication Association (USECA) w1ikatarrldotnet www.usecaarc. com
Re: [Repeater-Builder] Site Generator - First 09 War Story
I have a buddy who lives in Maine and moved into a new house a couple of years ago. He lost power to the house back in the middle of the summer last year and determined that the problem was somewhere between his house and the power pole. He started digging up the line and got all the way to the middle of the street where he found the dirt he was digging up was still warm. (power had been off several hours by that time) The power junction in the middle of the street was where the fault was found. In his case he found that he was responsible for all the circuit all the way back to the distribution pole and had to bite the bullet and pay for a new line installation. I know that in my case in North Texas, the power company is responsible for the line all the way to my meter box, but in his case, this was not so. 73 - Jim W5ZIT --- On Thu, 1/8/09, DCFluX dcf...@gmail.com wrote: From: DCFluX dcf...@gmail.com Subject: Re: [Repeater-Builder] Site Generator - First 09 War Story To: Repeater-Builder@yahoogroups.com Date: Thursday, January 8, 2009, 11:08 AM I'll see your genset woes and raise you 2 breaks in a sites power line. This is at KZKE-FM. In 1975 some idiot buried at least 4640 feet (measured with a GPS) of 00 gage aluminum. I should also mention that this is spliced together power pole drop line and was not meant to be buried. When the ground gets wet the weight shifts and rocks skin insulation off the line. The result is what can only be considered an electrical leak. Electricity conducts literally to ground. The result is the aluminum wire reverts back to alumina, a fine white powder based on bauxite that is a ceramic. The current conditions are text book classic for frozen tundra, But things have improved. Last week it was ankle deep snow in most places and knee deep in some. Now it is just mud. Mud, mud, sticky mud, mud in the water, do you understand that? I even found mud in sealed containers there was so much of it. We spent all day yesterday digging holes and still didn't find the break, and there are 2 different breaks by my reckoning. Station has been without power since Christmas. Pretty much my weekend is going to be shot. Planning on renting a Bobcat with a hoe and tracks. The ground is still too wet to efficiently dig with a shovel. __,___
Re: [Repeater-Builder] CAT300DX Programming
Alex, I operated a CAT300 with a two tone rising bubble up for about 15 years before linking that controller to another repeater last year. At that time I changed the CAT300 courtesy beep to a chime since I was getting a two tone DTMF courtesy beep through the link, indicating that the repeaters are linked. A local user on the CAT300 repeater hears the two tone DTMF plus chime as long as the repeaters are linked, and hears only the chime if the repeaters have been disconnected. Details of the operation and combining the CAT300 with the RLS1000 are contained in the forum: http://sbarcnm.org/forum/index.php?board=3.0 A lot more info there than you need, but it explains how I used the courtesy beep as telemetry to show the state of the system - linked or unlinked. 73 - Jim W5ZIT --- On Wed, 1/7/09, Alexander N Tubonjic kg4...@yahoo.com wrote: From: Alexander N Tubonjic kg4...@yahoo.com Subject: [Repeater-Builder] CAT300DX Programming To: Repeater-Builder@yahoogroups.com Date: Wednesday, January 7, 2009, 2:05 PM I'm in the process of programming up a new controller on my repeater (CAT300DX) and I think I've got everything setup the way I want it except for the courtesy tone. I was just wondering what others were using as the courtesy tone on their CAT300s. Any DTMF stings to play with and get ideas from would be appreciated. If anyone has any hints/tips/tricks/ cool ideas of things to program into the controller I'd appreciate hearing them as well. Lastly, if anyone has a copy of the CAT300DX programming software (ED-300W) they'd be willing to loan out you would be my hero. Thanks. Alex
Re: [Repeater-Builder] Problem remote base linking of 2 repeaters using CAT 300 DXL controller
Chris, here is a link to a GE Mastr II system I put together last summer. It uses a CAT300 (an old model without the Link capability) with the RLS board. http://sbarcnm.org/forum/index.php?topic=108.0 Using the older CAT300, only two remote base connections are available since there was no port on the original controller for a link. One thing I noticed was that the CTCSS signal from the link radio was not used in the internal control path of the RLS board. I changed the recommended CAT connections between my CAT300 and the RLS board to use the CTCSS signal instead of the COS signal. The COS signal was still used internal to the RLS board to control the audio mute function. I had a special consideration for the transmitted CTCSS tone in that I needed to be able to in-band link to either repeater for a VoIP interface. I made some modifications to the TS-64 MastrII tone board to only transmit a tone while a signal was present on the input of the repeater or link. I used an in-band link to another 2 meter repeater located about 10 miles away and used a GE Mastr II mobile with the PA removed as the link radio. The 250 mWatt signal into a 3 elememt beam located about 15 ft below the repeater DB-224 antenna provides a fully quieted signal for the other repeater, and the receive signal from the other repeater is fully quieted into the link radio (with some desense I am sure). The schematics for all the interconnections for the repeater are documented in the link above. 73 - Jim W5ZIT --- On Mon, 12/29/08, w4vx_chris w...@charter.net wrote: From: w4vx_chris w...@charter.net Subject: [Repeater-Builder] Problem remote base linking of 2 repeaters using CAT 300 DXL controller To: Repeater-Builder@yahoogroups.com Date: Monday, December 29, 2008, 1:40 PM Fellow repeater builders, I am a relative novice at repeater linking and need some trouble shooting/system design advice. I have a 440 repeater with 3 two meter remote base radios tied together using the CAT 300 DXL controller with the RLS board. The remote base radios are tuned to local repeaters that we would like to link together. Individually, each remote base radio works fine meaning I can turn it on with via 440 repeater and qso on the target repeater. Also, another local repeater with a 440 remote base is able to link the 440 repeater and when I turn on one of the remote base radio and link in another 2 mtr repeater it works fine (repeater key up and down like one big repeater). The problem arises when I try to use the two or more 2 mtr remote base radios to link two 2 mtr repeaters together. The system comes up stays up - never unkeys. Is this a hang time issue? Or is there something wrong about trying to link two repeaters on two meters with 2 meter remote bases through a 440 machine - usually folks target the 440 repeater with a remote base not the other way around? Could it be a controller setting issue? I am really stuck at the moment and I appreciate any thoughts you may have. It sure would be nice to have these repeaters linked for our nets and is generally kinda cool if we can pull this off. Vexed in Virgina, Chris W4VX
Re: [Repeater-Builder] VHF Unified Chassis Micor
Find the two speaker pins on the audio output module and with the module removed, check for continuity across the speaker leads. If you check from the output module end, you will hear the ohm meter put enough current through the speaker to hear a scratch in the speaker each time you connect the leads. An older analog meter will work a lot better for this test, as the R X 1 scale puts considerable current out through the leads. Checking this way will not only test the speaker but will also test the harness and any switching in the circuit. I had a problem with a GE speaker that I finally tracked to a blown fuse inside the speaker module that was not even on the schematic. 73 - Jim W5ZIT --- On Mon, 12/29/08, Terry wx3m.te...@gmail.com wrote: From: Terry wx3m.te...@gmail.com Subject: [Repeater-Builder] VHF Unified Chassis Micor To: Repeater-Builder@yahoogroups.com Date: Monday, December 29, 2008, 3:22 PM From retired parts, I am attempting to assemble a VHF Micor Unified chassis into a repeater. I already succesfully assembled the UHF model. I can not under any circumstances get any local speaker audio from the VHF chassis. The receiver is working and producing discriminator noise, measured at receiver pins 15 and 16.and on meter position 5. The audio squelch board works in another station. The audio pass board is good.(tried 2 other working parts from mobiles) Jumpers 1, 4, and 5 on the TLN 5644 backplane are in. J5-14 is jumpered to J5-19 On the backplane board, where the 30 receiver interconnect board pins come through, pin 6 to 14 in jumpered. J2 19 is jumpered to 20 What say you? Thanks, Terry _._,___
Re: [Repeater-Builder] Re: Helper Instruments
I went a step farther with my handheld Bearcat scanner and placed it in a steel pie cake pan with a cover I made from aluminum flashing. A few clothes pins around the cover sealed the signal up so that the only external signal came from the BNC feed through connector mounted on the side of the cake pan. I put a 10 dB pad internal between the scanner and the connector and then used a step attenuator external to the cake pan to set the level to the receiver I was trying to tune. I used it to tune a transmitter to frequency also by zero beating the Bearcat signal into a receiver. My Bearcat had a 10.8 mHz IF and I kept a calculator handy to add 10.8 to whatever frequency I wanted. The second harmonic of the LO in that old handheld worked great to intercept the analog cell sites in the area. You could take the antenna off and the reception did not change on the cell frequencies. Setting the cell frequencies minus 10.8 divided by two then plus 10.8 gave me the 440 frequencies to program into the scanner. 73 - Jim W5ZIT --- On Thu, 12/25/08, n...@no6b.com n...@no6b.com wrote: From: n...@no6b.com n...@no6b.com Subject: Re: [Repeater-Builder] Re: Helper Instruments To: Repeater-Builder@yahoogroups.com Date: Thursday, December 25, 2008, 11:44 AM At 12/24/2008 12:45, you wrote: The SM-512 is a service monitor that covers 1 to 512 MHz if memory serves correctly. It has a built in Sinadder and Millivolt meter. The system was designed around a Bearcat scanner. When Bearcat quit making ...and everyone thought I was nuts for using a Regency scanner as a deviation monitor signal generator. Bob NO6B ,___
Re: [Repeater-Builder] Six Meter Repeater Noise Issues
I got a first hand lesson in the technique Burt describes from K3RFI, the ARRL power line noise guru. He came to my QTH in response to a complaint I filed with the FCC through ARRL and showed me the 'fingerprint' method he uses to locate a noise source. When a breakdown occurs causing an RF noise, the arc may spark several times over the peak of the cycle and counting the number of spikes gives you the fingerprint of an individual noise source. K3RFI connected his service monitor to my HF antenna and noted the fingerprints of several noise sources and then worked with the power company to locate the individual noise generators. In my case, he checked on three consecutive days and found three different sets of noise sources. I have a 110 KV power line running overhead in the location where I spend the summer, and it was an old line with a lot of loose hardware problems. In my case, the consensus of opinion by K3RFI and the ARRL was that I should move to a quieter location. I have fought that problem for over 20 years now, with the local power company and with the ARRL/FCC complaint route and the noise is still there. I don't even bother to put up an HF antenna at that location any more. Noise on the 2 meter band is always pegged out on a receivers S meter. It does taper off a lot at 440 for whatever that is worth. 73 - Jim W5ZIT --- On Thu, 12/25/08, Burt Lang b...@gorum.ca wrote: From: Burt Lang b...@gorum.ca Subject: Re: [Repeater-Builder] Six Meter Repeater Noise Issues To: Repeater-Builder@yahoogroups.com Date: Thursday, December 25, 2008, 12:18 PM I have found a simple way to verify if noise is coming from a power line arc-over. Any such noise generated by a power line will only occur as the voltage on the line approaches peak and it will be synchronized to 120 Hz. Put an oscilloscope on the audio while feeding an unmodulated carrier into the receiver and set the time base trigger to 60Hz. If the noise is pulsing and stays solid on the scope display, you have power line noise. If it is steady (not pulsed) and not synchronized to 120 Hz, the power line is not the culprit. Burt VE2BMQ .
Re: [Repeater-Builder] NHRC-Squelch Board
Bob, my impression (I did not make any measurements) was that the short squelch tail did not change any with the mod. I had a mixture of base station and mobile squelch modules in my base station repeaters, and the biggest problem I had was with the base station modules. One of the capacitors was completely missing in those modules (as pointed out in the mod instructions). Those modules with the missing capacitor were the ones with the worse problem when a noisy signal was dropping out intermittently with the multipath. My impression of the tail with a very weak signal was that the squelch stays open for about 200 msec when the signal goes away. I tried both the 3.3 uF and the 4.7 uF caps and could not tell much difference. Both worked out just fine. I did find several different layouts for the boards and had to verify the LSI chip part number and then trace the leads from the right pin back to the correct capacitor. But all responded OK to the capacitor when modified. 73 - Jim W5ZIT --- On Wed, 12/24/08, n...@no6b.com n...@no6b.com wrote: From: n...@no6b.com n...@no6b.com Subject: Re: [Repeater-Builder] NHRC-Squelch Board To: Repeater-Builder@yahoogroups.com Date: Wednesday, December 24, 2008, 12:46 AM At 12/23/2008 09:09, you wrote: For the GE Mastr II users following this thread, be sure to check the mod shown here: http://www.repeater -builder. com/ge/mastrIIsq uelchmod. html I have this mod in all the repeaters I have built and am very pleased with the operation. It resembles the dual squelch operation of the Micor in that it closes very fast with barely a click on a fully quieted signal, yet does not close during a mobile transmission that is picket fencing. I have not needed to use an audio delay module to have a very good sounding repeater with no long open squelch bursts. Any idea as to how much the short squelch tail is lengthened by this mod? Without the mod the G.E's short squelch is a bit longer than the Micor (~6 milliseconds for the Mastr II vs. ~2 for the Micor) Bob NO6B ,_._,___
Re: [Repeater-Builder] NHRC-Squelch Board
For the GE Mastr II users following this thread, be sure to check the mod shown here: http://www.repeater-builder.com/ge/mastrIIsquelchmod.html I have this mod in all the repeaters I have built and am very pleased with the operation. It resembles the dual squelch operation of the Micor in that it closes very fast with barely a click on a fully quieted signal, yet does not close during a mobile transmission that is picket fencing. I have not needed to use an audio delay module to have a very good sounding repeater with no long open squelch bursts. This was very apparent while using a Zetron 38A controller which issues the courtesy beep with hardly any delay from the squelch closure. A mobile picket fencing without the squelch mod resulted in a series of beeps that completely destroyed the intelligibility of the transmission. Until the mod described above was incorporated the beep had to be disabled and in one case the repeater was operated open squelch for almost a year before the mod was incorporated. The long burst of squelch noise while the CTCSS decoder was deciding that the tone was gone was very annoying. With the incorporation of the mod, an estimate of the signal strength can be made while listening to the end of the transmission. A fully quieted signal results in a click while a weaker signal has a short burst of noise at the end of the transmission. 73 - Jim W5ZIT --- On Mon, 12/22/08, Cort Buffington c...@lawrence-ks.org wrote: From: Cort Buffington c...@lawrence-ks.org Subject: Re: [Repeater-Builder] NHRC-Squelch Board To: Repeater-Builder@yahoogroups.com Date: Monday, December 22, 2008, 9:04 PM Motorola copied their own Micor squelch action in the MSR2000 audio card without using the Micor chip. Looking at the manual for it makes a nice bit of context for the micor circuit. I think Kevin hit the nail on the head with the really, REALLY good squelch action you can set right at the ragged edge without false triggers. Since I use audio delay boards in my repeaters, the micor's closure action is not as nice as the really really nice hairy edge. I've actually noticed that the MSR2000 works just as well for this... and dare I say... personal preference, prefer it to the Micor. I've played with several noise squelch designs. Zetron even included a bi-level squelch in one of their controllers. .. 45? 48? I don't remember now. In any event, if it's the no noise-burst you're looking for then simply adding another comparator that triggers about 10db above the first (assuming you want it Motorola style), and when it triggers it disables the time delay circuit of the first (read: discharges the timing capacitor). When the signal is removed, the timing capacitor has no time to charge between the time the strong signal comparator shuts off and the weak signal one does, hence no noise burst. If you have a spare couple of hours, playing with building squelches if really pretty fun and easier than you might think. Grab a breadboard, your favorite active filter calculator, a couple of op amps and a couple of comparators and have fun! 73 DE N0MJS On Dec 22, 2008, at 7:05 PM, Kevin Custer wrote: Jordan, et al, The RLC-MOT circuit uses the famous Motorola MICOR squelch chip, so it works identically to what is found in the MICOR. Motorola decided some time ago to end the production of the chip, and I suspect the recent jump in cost is a result of this. As Scott has mentioned, I did a test of some of the commercially available add-on squelch boards that were advertised about two years ago. This included the NHRC-Squelch, the CAT SQ-1000, and the Link-Comm RLC-MOT. The following is a personal opinion - no more, no less. The best one I found is the RLC-MOT, but then again, I find no fault with the action of the MICOR squelch. In my opinion, there is no better. The other two work fairly well, and I don't remember if one was any better than the other. The biggest fault I found with the latter two units is (in my opinion) they don't have enough sections of high-pass filtering, and low frequency noise is considered in the evaluation. This tends to make the user set the squelch tighter than he/she should have to - - to keep the unit from falsing. This may not be a big deal for some, but I like to have a squelch I can set on the hairy edge without falsing, like the MICOR squelch. Both the NHRC and the CAT have near instant turn off when the carrier is near full quieting and then removed. They both have 'variable' hysteresis - as the signal is reduced, they produce a longer noise burst after removal of the carrier. In the NHRC, there are four progressive steps with differing time - depending on how it's configured. The manual for the CAT unit doesn't offer how the time delay is handled. They both use a processor to evaluate the noise and set the amount of hysteresis. The MICOR has only two different hysteresis levels. As the
Re: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...)
This probably will not work on the Mitrek since it may not use slugs to tune the coil, but I had a problem with a crystal on a Delta radio that would not go low enough in frequency. I removed the slug from the F2 coil and ran the slug for the F1 coil through max inductance and then added the second slug on top of the first. The combined slugs allowed me to net the crystal. 73 - Jim W5ZIT --- On Sat, 12/20/08, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: [Repeater-Builder] Converting a Range 2 VHF Mitrek to Range 1 (WAS: Holiday Special...) To: Repeater-Builder@yahoogroups.com Date: Saturday, December 20, 2008, 9:27 AM Only one of the five front-end coils for a Range 1 VHF Mitrek (HLD4081, 136-146 MHz) is still available from Motorola Parts. That one is part 2480032A07, the violet coil in L1, for $ 4.15. The only option may be to tack on some extra wire to the existing coils. Although modifying the tuning screws may work, I suspect the Q will suffer. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Kevin Custer Sent: Friday, December 19, 2008 9:30 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver conversion from W3KKC Tom, Okay I guess I should ask if replacement coils for the Mitrek are still available from Motorola, and if so, at what cost? If they are no longer available, or are cost prohibitive, send me one of your Mitrek receivers and I'll see if I can come up with a new set of coils that properly tune the whole 2M band. I guess at this point we should go to private email. Kevin Hello Kevin Thanks for your reply. Your statement is correct in that all of the receiver coils begin to tune at the bottom of their travel. I have even tuned two or three too far and they dropped out with the resulting work to retrieve the screws. When tuned as best I can for sens the s/n ratio is 1+uv at 12db sinad. The original frequency sens was less than 1uv-usually about .3uv for 12db sinad. Replacing the coils are about the only solution I know of for these high split VHF units. I have in the past replaced two sets of receiver coils with Motorola coils and found I have good sensitivity as before modification. The transmitters all tuned well on this split and gave rated or more power output. The Mitrek coils looked very much like the Micor coils. I have replaced probably a half dozen Micor receiver coils proscured from Motorola in the past 20 or so years. Thanks. 73 de Tom Manning, AF4UG - Original Message - From: Kevin Custer mailto:kug...@kuggie. com To: Repeater-Builder@ yahoogroups. com mailto:Repeater-Builder@ yahoogroups. com Sent: Thursday, December 18, 2008 10:02 PM Subject: Re: [Repeater-Builder] Holiday Special - MICOR 2 meter receiver conversion from W3KKC Tom, You say you find similar operation on 4 or 5 units. By that do you mean they won't make book specification on any frequency below 146 MHz? If that is the case, I would believe something is wrong. I have seen many Mitrek high-band receivers that were tuned for 144 something and had very good sensitivity. Let me ask you this When tuned at 144.89, is the front-end tuning all one ended, or is there adjustment to spare? In other words, can you tune the front-end without the fear of the tuning screws falling into the casting? If you have room left to go lower in frequency, then the front-end is not the problem, and you'll need to look elsewhere for the lack of sensitivity. Another question - do these 4 or 5 units tune and make book spec sensitivity on their original high-band channel? I guess what I'm saying is I doubt the problem is the front-end helical resonators, but if there is a need for a conversion I'm not opposed to looking into making a modification available, if it is needed. If there are others on the list that have had good luck with the Mitrek on frequencies below 146 MHz, please chime in and let us know what you have and how well it works. Kevin Hello Kevin You are correct on your freqs for xmit and rcv. The Mitrek units I have will only tune receive to 146.00Mhz. This leaves more than one meg to go to meet tolerance on 144.890. I have tried 4 or 5 units and find similar operation of all. This is the reason for my question about the Micor coils working for Mitrek. Thanks. 73 de Tom Manning, AF4UG
Re: [Repeater-Builder] Yet Another split antenna Question
Here is yet another approach from back in the '70s: The 146.94 repeater in Ft Worth was located on a 1000 ft tower on the east side of the city. It utilized a solid state converter for 2 meters down to the 10 meter band where plenty of low band receivers would work. I think it used a piece of RG-58 to route the 10 meter signal to the bottom of the tower. The transmitter was located at the 500 ft level and several transmitters were utilized. a separate 145.76 repeater was implemented from this same receive antenna with a directional antenna to serve Ft Worth only. Receivers for 146.34, 146.94, 146.16 and maybe 146.76 were all connected to the 10 meter down converter output. Receiver outputs were all routed to 440 transmitters and receivers to allow interconnect at a trustee's home. I once saw this system work a skip situation with the 146.94 repeater in Little Rock Arkansas where a station on the Ft Worth repeater was repeated on the Little Rock repeater and a station on the Little Rock repeater was repeated on the Ft Worth repeater. Granted when the Little Rock repeater stood down, the Ft Worth repeater would howl, but as soon as a signal appeared on 146.94 the incoming signal would override the local .94 output and through the 440 link it was repeated back on the local .94 transmitter. I never knew how much isolation this represented, but it was really a nice set up for a repeater system. Alas - it all went away when the 1000 ft tower was removed. I worked this repeater regularly from my mobile Progress Line 60 watt radio in Greenville, TX - 90 miles away. 73 - Jim W5ZIT --- On Wed, 12/17/08, kb5vjy jholl...@nbc10news.net wrote: From: kb5vjy jholl...@nbc10news.net Subject: [Repeater-Builder] Yet Another split antenna Question To: Repeater-Builder@yahoogroups.com Date: Wednesday, December 17, 2008, 11:04 PM Folks, I have read just about every split antenna post that I can find.. I hate to be a yet another poster but here is my situation. I just want to know if it is do able. And what problems I might run into. After months of waiting, I have been issued a repeater pair of 147.255 for a long range 2m repeater that will be installed. This is my first 2m repeater, but I do have 3 70cm repeaters (all Mastr II's).. My situation is the following: I have a Mastr II Station 100w Cont. Duty PA for the project... I still have to order the xtals. I will run a PL as needed on 127.3. The controller will be a CAT (version unsure of) I have a 2000' broadcast tower with a platform at 1300' and another at 1000'. There is a DB 224 mounted under the 1300' and one under the 1000' platform with a section of 7/8 feedline running from the top platform and the bottom platform. There is a full rack size NEMA 12 enclosure on the 1300' platform. After Feb '09 there will be NO VHF transmitting equipment on this tower at all. The closest transmitter is 6 miles away. What I would like to do, is mount the radio in the enclosure at the top platform. Use the top DB 224 for the Receive antenna, and the 1000' DB 224 for the Transmit antenna. What are the problems that I will run into with this situation, and should I look for some type of filter for the receiver. I do plan on putting an APRS Digi at 1300' as well moving one of my 70cm repeaters to the same platform some time early next year. Any comments would be helpful. Thanks.. 73 de Joe KB5VJY Sorry.. RTTY dayz!
Re: [Repeater-Builder] VXR 7000 with desense
I don't know what type of service monitor you are using, but I tend to use an iso-tee to measure desense with the duplexer hooked to a dummy load through the iso-tee. It might be possible for the service monitor to contribute to some signal reflection if it is used as the power termination. Make sure the cables to the duplexer are double shielded, like RG-214, and inspect the connectors to make sure all the grounds are in good shape. Check the internal cables in the VXR-7000 for the same potential problems. I may be preaching to the choir and if so I apologize. 73 - Jim W5ZIT --- On Wed, 12/17/08, pontotochs pontoto...@bellsouth.net wrote: From: pontotochs pontoto...@bellsouth.net Subject: [Repeater-Builder] VXR 7000 with desense To: Repeater-Builder@yahoogroups.com Date: Wednesday, December 17, 2008, 4:04 PM Hi, I've checked the previous posts on this issue, but I am hoping that there is more light to be shed. We have a VXR 7000 that has had issues for a while as a two meter repeater. In the shop we set it up with its DB 4026 duplexer and 50 ohm dummy load and monitored the output power with a Bird thru line watt meter. We used a service monitor to inject the RX signal to get 10 dB quieting (approx 0.2 micro volt). Put the unit into repeat mode and the repeater will cycle (go in and out of transmit) until the RX signal is increased about 20 to 25 dB (approx 3.6 micro volt). Looking at what is coming in the receive port with the transmitter is keyed is about -75 dBw (50 watt out with about 95 dB of isolation) at the TX frequency, and there is little to no hash at the RX frequency - seeing the noise floor of the spectrum analyzer (-120 dB). Put the 7000 into base station mode, hooked up second signal source, set first signal source to give 10 dB quieting at the RX frequency (0.2 uV), set the second signal source to emulate what we saw from the duplexer (79 mV at TX frequency) and there was no desense. Increased the simulated TX voltage to better than 1 volt and still no desense. My thought is that something has gone bad internally within the 7000. Is there something else I need to try? Thanks in advance for your help. Regards, Rick, N5RB
Re: [Repeater-Builder] Manual needed Motorola S-1320A Signal Generator
Both my Motorola Signal Generators developed an intermittent with the 1 kHz tone and I pulled the units out of the case and cleaned the pins on the PC cards. The old red ruby eraser trick worked like a charm. I also found a light coating of a greasy film on the contacts which I cleaned with a Q tip and alcohol before applying the eraser. I use mine for duplexer tuning since they have a lot lower signal leakage than my service monitor. A double shielded cable between the generator and the 6 dB pad at the antenna connection allows me to use a handheld radio to tune for max on the pass and also tune the nulls. I use another 6 dB pad at the port output to the talkie and a 50 ohm load on the other port. 73 - Jim W5ZIT --- On Sat, 12/6/08, Arthur R Carlson [EMAIL PROTECTED] wrote: From: Arthur R Carlson [EMAIL PROTECTED] Subject: [Repeater-Builder] Manual needed Motorola S-1320A Signal Generator To: Repeater-Builder@yahoogroups.com Date: Saturday, December 6, 2008, 7:34 PM I have 2 Motorola S-1320A-1 Solid state signal generators in my shop that I need to service. One has intermitant 1000hz tone sometimes it works and usually when you need it it doesn't. The other has a power supply problem. I would like to find a manual for this either borrow, rent or buy. I use it for repeater site work and it takes a beating but I can't afford to upgrade right now. Does someone out there have a manual on the shelf that would be willing to assist. Thanks Art. Can respond off list to [EMAIL PROTECTED] com
Re: [Repeater-Builder] Interfacing our repeater to skype or other VOIP client
This one has an easy solution. Use the SignalLink USB interface to get Skype to your radio. It detects the incoming audio from Skype and keys the transmitter, and the system is full duplex, so you have receive audio available back into Skype with no VOX to fool with. Be sure to secure your Skype connection so there is no chance of someone other than yourself getting back into the system. 73 - Jim W5ZIT --- On Mon, 12/8/08, Ian Miller [EMAIL PROTECTED] wrote: From: Ian Miller [EMAIL PROTECTED] Subject: [Repeater-Builder] Interfacing our repeater to skype or other VOIP client To: Repeater-Builder@yahoogroups.com Date: Monday, December 8, 2008, 11:38 AM Hi guys. I'm not sure how legal this is, but I guess the principle is the same as IRLP or Echolink, except, has anyone interfaced their repeater to a VOIP client, like Skype for instance, so one can access their repeater from a Blackberry-type device? Any info would be appreciated. Thanks Ian VA2IR VE2RMP Repeater group
Re: [Repeater-Builder] Used Outdoor Repeater Cabinets?
Our club recently bought a cabinet from these folks: http://www.ddbunlimited.com/OD-50DX-outdoor-nema-enclosures.htm We were very pleased with the way it was built and is has been in service for about 3 months now. Not cheap (around $1500) - but a very good cabinet. 73 - Jim W5ZIT --- On Mon, 12/8/08, Alexander N Tubonjic [EMAIL PROTECTED] wrote: From: Alexander N Tubonjic [EMAIL PROTECTED] Subject: [Repeater-Builder] Used Outdoor Repeater Cabinets? To: Repeater-Builder@yahoogroups.com Date: Monday, December 8, 2008, 3:16 PM Does anyone know of any sources for used outdoor repeater cabinets? I've gotten permission from a local tower owner to locate an amateur repeater on their tower but one of the stipulations was no access to the existing equipment room. After a quick search of Tessco I see the cheapest outdoor enclosure is going for around $2k. Does anyone know where one could be found for cheap? Any information is greatly appreciated, thanks. Alex
Re: [Repeater-Builder] How to set up a basic crossband repeater system in Public Service
Bryan, I can recommend the NHRC-4 controller for the service you want to implement. I'm not sure but I think the ICS-Basic you mentioned is a repeater controller that does not have the second port to control your link. I have built up 3 of the NHRC-4 controller kits and used them in two port service where the main port controls a repeater and the second port controls a simplex radio on another band and can recommend them for this type of service. They were easy to build, and the later control system is very easy to set up using the zone type of control groupings. I ordered the remaining parts from Digikey for my controllers, and the suggested part numbers in the manual work out fine. With a well stocked junk box, you may have a lot of the parts. I did not have to order a single resistor or bypass capicator for my kits. You could probably get started using the existing VHF radio, and if it proves to have too much coverage you could change the radio. When working with hand held radios you may find that the extra power is useful even when the handhelds can't talk back to the simplex port. Being able to copy EMCOMMS even when you can't talk back can be of some use. Finding the correct interface for the radios to the controller can be a pain, but can usually be accomplished. The NHRC controller can handle receive audio that is already equalized, or can equalize the audio from the receiver discriminator inside the controller. Same with the receive audio from the VHF simplex radio. 73 - Jim W5ZIT --- On Sat, 11/29/08, bkcarter33 [EMAIL PROTECTED] wrote: From: bkcarter33 [EMAIL PROTECTED] Subject: [Repeater-Builder] How to set up a basic crossband repeater system in Public Service To: Repeater-Builder@yahoogroups.com Date: Saturday, November 29, 2008, 12:03 AM My local Community Emergency Response Team (CERT) has recently obtained a UHF repeater (ICOM CY-F221S). It has two ICOM F221S radios linked together in a nice rack mount box. It has also been set up with a remote mic and speaker off of the outputs on the chassis back panel. The CERT group is licensed for the UHF repeater frequencies and they are in the public service band. They also have a simplex VHF frequency in the PS band (old police frequency) licensed. They have a number of Motorola HT radios (CP200) that operate on the simplex VHF frequency. They are looking at obtaining additional UHF HT radios in the future but would like to be able to use the equipment they have if they can get it to work together. I am familiar enough with electronics to be able to follow directions, but not enough to design anything beyond a basic switch box. I am a network engineer professionally so I am pretty well versed in those areas, and understand logic control pretty well. I am a technician class ham, but don't know a lot about RF as I have not had that much experience in it. I would like to accomplish the following and would love to receive some guidance from someone who has the knowledge to instruct me: I would like to set up a cross band link for them from the UHF repeater, to a VHF radio: This would allow someone on the UHF side to transmit to the repeater, and also cross-band repeat to the VHF side. The VHF side would be able to transmit on the VHF simplex frequency to the cross band side, and it would repeat onto the UHF side. I realize that this would NOT provide VHF to VHF repeating, and that is okay. I want to provide a way that the cross band link can be enabled and disabled by remote DTMF tones so that the bands can be separated when desired. I already have an old Motorola Spectra police radio operating on the VHF side at the site, and it has a dedicated antenna. It puts out 110W which is way too much for what we need. I was thinking about getting an ICOM F121S radio, Astron power supply, and ICS basic controller board. Using the existing VHF antenna, I would hook up the new ICOM (50 watts or less). Now I just need to tie the ICOM repeater, controller, and new radio together into a cross band system of sorts. Am I on the right track? I need some general guidance that can tell me, try this, this, and this. Here is what equipment you could use, and here is how you could tie it together. I have the schematics for the repeater available to me. If I don't want to spend the money for a new ICOM F121S radio, then what else could I connect easily that I can program and would be able to get at a reasonable price. This is all being done as volunteer service so inexpensive is best, but I want to avoid cheap equipment. Thanks for any help you could provide me, 73 Bryan Carter KE7GVJ Kaysville CERT Administration _,___
Re: [Repeater-Builder] Need SWR meter recomendation (Bird 43)
In using the Bird 43 outside the bandpass listed on the slug, I have found that the meter works very well for tuning an antenna for minimum SWR. The power readings on the meter are just not accurate when the frequency being measured is outside the slug bandwidth. I have not gone all the way down to HF to make a comparison, since I have some HF slugs, but the variety of VHF/UHF slugs I have work fine to tell me that something is wrong with an antenna or feedline, or even a Z Matcher adjustment when used out of band. You just can't record the power readings as actual. 73 - Jim W5ZIT --- On Tue, 11/25/08, Keith Foor [EMAIL PROTECTED] wrote: From: Keith Foor [EMAIL PROTECTED] Subject: Re: [Repeater-Builder] Need SWR meter recomendation To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 25, 2008, 11:16 PM The design is better than anything else because of the way it samples. Cheap meters measure RF voltage, that with a high impedance load can rise greatly, showing a very inaccurate reading. Bird slugs measure current, and they are band pass. So it you use a slug for HF to measure VHF it just will not work. A cheap HF voltage meter will show your 40 watt VHF radio doing 75 watts.
Re: [Repeater-Builder] Replacement Dual-Band Antenna......
You may find that a lot better operation will be had with a VHF antenna used as a VHF/UHF dual band antenna. The 1/2 wave VHF dipoles are 3/2 wave on UHF and a current feedpoint is the same point on the dipole on VHF as it is on UHF. My experience has been on a DB-224 type antenna, but I suspect that other exposed dipole co-linear antennas would work the same. Someone here on the group published a pattern on a vertical array of dipoles operated on the third harmonic with the wide spacing that would be in effect, and it showed many lobes in the vertical pattern. But it did have one of those lobes at the 90 degree broadside elevation to the antenna, and other folks reported that they had operated the antenna this way. I used a DB-224 as a 440 repeater antenna with a 2 meter remote base diplexed into the same antenna and was able to use it successfully for several years. The range of the 20 watt 440 repeater was about the same as the 2 watt 2 meter transmitter on that same antenna. 73 - Jim W5ZIT --- On Thu, 11/27/08, Mark Christian [EMAIL PROTECTED] wrote: From: Mark Christian [EMAIL PROTECTED] Subject: [Repeater-Builder] Replacement Dual-Band Antenna.. To: Repeater-Builder@yahoogroups.com Date: Thursday, November 27, 2008, 4:34 AM Kevin, Hey fellow trustee. My name is Mark (KB6SRT) and I am the trustee of two repeater systems in the Southern California area. This is just a note to let you know that when we were strapped for money in our early years and we only had the uhf antenna, I used a Dodge-Phelps 8 bay, dual-eared folded dipole array for dual band operation and it worked well until we could get a decent dual band antenna. Though it was a uhf antenna, it resonated on vhf well enough and had decent SWR to allow regular use. The really nice thing about this dual-eared dipole is that it had folded dipole on BOTH sides of the pole (dual-eared) so the coverage was quite impressive and the input power was up to 250 watts. So any loss in power was made up for with an amp. Just a suggestion that it doesn't HAVE to be a dual band antenna. Try resonating vhf off a uhf antenna. Hope all works out for you and Happy Thanksgiving! -- Mark Christian KB6SRT -- Trustee. - FCARA 146.610 (-) pl 103.5-Echolink Node-44576 445.760 (-) pl 103.5-IRLP Node-3952 [EMAIL PROTECTED] com _ __.
Re: [Repeater-Builder] GM-300 Repeater (was 900mhz , DTR, 906 to 923.75 MHz FHSS)
Andre, I am not that familiar with Motorola products, but I understand that a number of different radios have a standard 16 pin connector for external interface, and that the connector pin functions for most of these radios are the same. I have no idea if the handheld radios you mention have this connector, but I doubt it, since the connectors are pretty large to be able to fit on a talkie. 73 - Jim W5ZIT --- On Tue, 11/18/08, ANDRE [EMAIL PROTECTED] wrote: From: ANDRE [EMAIL PROTECTED] Subject: Re: [Repeater-Builder] GM-300 Repeater (was 900mhz , DTR, 906 to 923.75 MHz FHSS) To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 18, 2008, 6:56 AM Jim, But it will work on the Motorola DTR (digital) FHSS handheld? I am worry about the FHSS. Thanks - Original Message - From: Jim Brown To: Repeater-Builder@ yahoogroups. com Sent: Tuesday, November 18, 2008 1:19 AM Subject: Re: [Repeater-Builder] GM-300 Repeater (was 900mhz , DTR, 906 to 923.75 MHz FHSS) Andre, a pair of Motorola GM-300 radios can be interconnected as a repeater using a cable available on eBay for about 10 USD. I have used two radios set up like this, one as the receive and the other as the transmit and they worked just fine as a repeater. No squelch tail on the simple cable, but no problem getting them to work. The cable has a pot to set the repeated deviation, and that is the only adjustment required. 73 - Jim W5ZIT --- On Mon, 11/17/08, ANDRE [EMAIL PROTECTED] com.br wrote: From: ANDRE [EMAIL PROTECTED] com.br Subject: Re: [Repeater-Builder] 900mhz , DTR, 906 to 923.75 MHz FHSS To: Repeater-Builder@ yahoogroups. com Date: Monday, November 17, 2008, 6:56 AM Benjamin, Do you know any brand, model? Thanks
Re: [Repeater-Builder] 450-460mhz Repeater Co-Channel Interference
For some PL decoders, a weak noisy signal will trigger the PL detect and let the signal through. On the other hand, if the co-channel signal happens to be using the same PL tone, it will get through also. A good PL decoder like the TS-64 will rarely false. I have a repeater configured so that either a quiet (20 dB quieting on a SINAD meter) or the correct PL tone will trigger the repeater. I tell users that if they are having problems holding the repeater to use the PL tone to extend their receive range. The PL decoder in my Zetron 38As will detect the tone and key the repeater when nothing but noise is heard on the output. I have to combine the PL with the COS to get normal operation from this setup. If you are using one of the older PL decoders such as one normally used in a mobile radio, I would suggest changing to a better decoder, like the TS-64. It will also encode and decode at the same time, saving having to install a separate encoder in a repeater. 73 - Jim W5ZIT --- On Tue, 11/18/08, ptt_pupil [EMAIL PROTECTED] wrote: From: ptt_pupil [EMAIL PROTECTED] Subject: [Repeater-Builder] 450-460mhz Repeater Co-Channel Interference To: Repeater-Builder@yahoogroups.com Date: Tuesday, November 18, 2008, 12:30 PM Can anyone tell me if there are ANY fixes for co-channel interference? What is the use of a PL tone if it isn't able to block out the co- channel users? Is it because the co-channel user is transmitting with more power and is able to break the PL tone? What are the expectations of a PL tone? When does it work and when does it not work? Are there other devices that can help all? Thanks in advance! ,_._,___
Re: [Repeater-Builder] Sinclair q202gc duplexers
Jason, if your duplexer is one of the older units using a dielectric rod to tune the notch, here is the manual: http://www.repeater-builder.com/sinclair/q202-208-218-tuning.pdf I have moved four of these duplexers down into the ham band by changing out the cable that goes from the cavity to the Tee from the old 10.5 inch dimension to new cables measuring 12.5 inches. The cavity tuned down from 170 mHz to the ham band just fine, but the notch would not work until I changed the cable dimensions. My duplexers were all cabled with RG-213 from the factory and I used RG-214 to replace the cables. I did not replace any of the other RG-213 cables in the harness. 73 - Jim W5ZIT --- On Fri, 11/21/08, kc7stw [EMAIL PROTECTED] wrote: From: kc7stw [EMAIL PROTECTED] Subject: [Repeater-Builder] Sinclair q202gc duplexers To: Repeater-Builder@yahoogroups.com Date: Friday, November 21, 2008, 10:03 PM I am new to the sinclair line of duplexers. I have a set of used vhf duplexers setup in the high vhf range. current freqs are 165.2375 and 165.1375. Has anyone had luck changing the coax harness to the longer 36cm and getting the duplexers to tune down to the two meter band? Thanks -Jason ,_._,___
RE: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation)
I was especially interested in the crystal checker. I had never thought about using an analyzer to check the series resonance of a crystal, but I'll bet it works just fine. Going to have to build up a little circuit to couple mine to a crystal through a 50 ohm resistor and get after the crystal stock. 73 - Jim W5ZIT --- On Sun, 11/23/08, Eric Lemmon [EMAIL PROTECTED] wrote: From: Eric Lemmon [EMAIL PROTECTED] Subject: RE: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) To: Repeater-Builder@yahoogroups.com Date: Sunday, November 23, 2008, 3:54 PM The file in question likely requires a later version of Adobe Reader than what is being used by those having problems. Simply download the latest version of Reader, and it will work just fine. I have Adobe Acrobat 7.0, and it opened the file with no errors. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Chuck Kelsey Sent: Sunday, November 23, 2008 1:00 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) Didn't work for me either. It indicated that the file was damaged when Adobe tried to open it. Chuck WB2EDV - Original Message - From: Bruce Bagwell To: Repeater-Builder@ yahoogroups. com mailto:Repeater- Builder%40yahoog roups.com Sent: Sunday, November 23, 2008 3:53 PM Subject: Re: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) I had no problem with the attachment. You do need Adobe Acrobat Reader to open this. If you do not have Adobe Reader, download it and I bet the attachment will open.
RE: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation)
I was especially interested in the crystal checker. I had never thought about using an analyzer to check the series resonance of a crystal, but I'll bet it works just fine. Going to have to build up a little circuit to couple mine to a crystal through a 50 ohm resistor and get after the crystal stock. 73 - Jim W5ZIT --- On Sun, 11/23/08, Eric Lemmon [EMAIL PROTECTED] wrote: From: Eric Lemmon [EMAIL PROTECTED] Subject: RE: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) To: Repeater-Builder@yahoogroups.com Date: Sunday, November 23, 2008, 3:54 PM The file in question likely requires a later version of Adobe Reader than what is being used by those having problems. Simply download the latest version of Reader, and it will work just fine. I have Adobe Acrobat 7.0, and it opened the file with no errors. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of Chuck Kelsey Sent: Sunday, November 23, 2008 1:00 PM To: Repeater-Builder@ yahoogroups. com Subject: Re: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) Didn't work for me either. It indicated that the file was damaged when Adobe tried to open it. Chuck WB2EDV - Original Message - From: Bruce Bagwell To: Repeater-Builder@ yahoogroups. com mailto:Repeater- Builder%40yahoog roups.com Sent: Sunday, November 23, 2008 3:53 PM Subject: Re: [Repeater-Builder] MFJ Analyzers (was Need SWR meter recomendation) I had no problem with the attachment. You do need Adobe Acrobat Reader to open this. If you do not have Adobe Reader, download it and I bet the attachment will open.
Re: [Repeater-Builder] 2.4 Ghz wireless radio and 145.410 repeater
I installed a remote receiver for a repeater this last summer at a site where a 900 mHz wireless distribution system, along with a 5.x gHz backbone was located. The site also had a 2.4 gHz local wireless router installed. In order to operate the remote receiver the squelch had to be as tight as it would go. Even then as soon as an input signal goes away you would hear a digital signal on the tail until the PL decoder runs down. The digital signal sounds a lot like 1200 Baud packet. This site is on a 60 ft tower, and a pager goes off on all channels as you walk up to the tower. A talkie at the tower site can not copy the repeater over the local noise from the digital system. About 200 ft from the tower the repeater is strong enough to override the digital and the remote receiver is usable with a talkie. Needless to say, we are looking for another site for the remote receiver. It is only useful for folks within a couple of miles with a talkie and within about 6 miles with a mobile. 73 - Jim W5ZIT --- On Thu, 11/20/08, n9lv [EMAIL PROTECTED] wrote: From: n9lv [EMAIL PROTECTED] Subject: [Repeater-Builder] 2.4 Ghz wireless radio and 145.410 repeater To: Repeater-Builder@yahoogroups.com Date: Thursday, November 20, 2008, 7:16 PM I just had a 2.4 Ghz internet wireless antenna mounted at the top of my 120' tower which is where the antenna is for the 145.410 repeater. I am getting intermod into the system that causes it to hang open. Anyone ever had these issues and how did you go about remeding the problem. And I can't shut off the internet as the family would hang me, and would rather not shut off the repeater. There is besides the TXRX duplexers two DB4001 filter duplexers on the system. Funny part is that once it starts the interference, I can remove antenna from the receiver and it continues to intermod until I kill the transmitter. I can hit the remote PTT and it will key the repeater, no noise into the system until I reattach the antenna port to the receiver. Thanks. Mathew
Re: [Repeater-Builder] Good Repeaters for UHF Ham Band
Our club budgeted for a Kenwood 750 repeater to replace an RCA TAC-200 mobile repeater we have had in service for 15 years. Replacing it was deemed necessary since repair parts are no longer available. I objected to this replacement from the start, wanting to put another GE Mastr II base station repeater in service to replace the RCA. I had no particular reason to not want the Kenwood repeater, but since the club operates another GE Mastr II base station repeater and our link radio is a GE Mastr II mobile with the final PA removed, I wanted to keep all the equipment the same, and I know that the GE equipment is reliable and performs well. My main detractors were convinced that a 15 year old repeater could not possibly work as well as a brand spanking new Kenwood 750. I had to disagree, saying that I thought the GE repeater would probably work better than the Kenwood in our particular application. We have a solar site, and the standby current draw of the GE with the audio amp disabled was far less than the standby current drawn by the Kenwood. The repeater sensitivity was also called into question as the Kenwood has better receiver specs than the GE. However the site has other radio equipment installed, and the site noise floor was not going to allow full use of the Kenwood sensitivity anyway. Long story short, I prevailed and we now have a GE Mastr II base station repeater with an in-band link installed with our two repeaters linked and operating as the club desired. The club also owns a GE Mastr II mobile which gives us a spare module for every part in the system except for the continuous duty PAs for both repeaters. The squelch mod has been performed on both repeaters giving slow squelch close for weak signals to combat picket fence noise, but allowing a snappy squelch closure for stronger signals without using audio delay modules. I firmly believe that the money allocated for the repeater was better spent buying a nice outdoor cabinet and new DB-224E antenna, and the $200 GE outperforms the Kenwood 750. For commercial applications I can see where the Kenwood provides a fast set-up and easy programming for frequency and features, where these factors are critical, but for amateur use where more time is available an older crystal controlled repeater can easily outperform the newer repeaters. If you are interested in this build, the progress was documented here: http://sbarcnm.org/forum/index.php?topic=108.0 The new repeater and link has now been in service for several months, and is performing very well. 73 - Jim W5ZIT --- On Fri, 11/21/08, John Transue [EMAIL PROTECTED] wrote: From: John Transue [EMAIL PROTECTED] Subject: [Repeater-Builder] Good Repeaters for UHF Ham Band To: Repeater-Builder@yahoogroups.com Date: Friday, November 21, 2008, 9:19 AM My ham radio club is ready to replace our 440 repeater. I have read the spec/data sheets on the Icom IC FR-4000 and the Kenwood TKR-850. Here are my questions: Are these among the best modern repeaters available? Is one or the other superior? Is there a different repeater you would prefer or recommend? What good/bad experience have you had with the Icom or Kenwood (or with related products)? Are there specific brands or models to avoid? Information that might be relevant: The repeater will be in a standard 19-inch rack mount cabinet. It will be inside, not exposed to the elements. It can be used with or without a power amplifier (5W in, 90W out). I would like the power out to be near the 90W. The frequency pair has 5MHz separation. TX is on 448.375MHz; RX on 443.375MHz. The duplexer is a Motorola T1504A I would appreciate the benefit of your experience. Thanks. John Transue, Trustee Vienna Wireless Society Vienna, VA _._,___
Re: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How???
Gervais, take a look at the link below for an interface to EchoLink for one of the PSE-508 controllers. http://www.pionsimon.com/w5zit.htm My original interface used the stock GE Repeater Audio and Repeater Control cards, and I found that the PSE-508 could be modified the same way. But you can see where the signals need to come from in the GE Repeater for an external link. Use the RUS signal through an inverter to key your PTT on the link radio, and connect the audio to your link radio in parallel with the repeater transmitter audio input. You will have to condition your CAS from the link radio to operate the PTT on the repeater while the audio from the link radio goes to the mic input screws as shown. The opto-isolators can be used for both purposes, one to key the repeater and the other to key the link radio. The circuit shown has some provisions to interface RS-232 signal lines which you will not need for a radio interface, so you will have to make some modifications. I think I ran off a schematic for a radio interface to the PSE-508 that I may be able to find and forward to you if you are interested. You are probably not using a PSE-508, but this may give you some ideas for your controller. 73 - Jim W5ZIT --- On Fri, 11/21/08, gervais fillion [EMAIL PROTECTED] wrote: From: gervais fillion [EMAIL PROTECTED] Subject: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How??? To: repeater-builder@yahoogroups.com Date: Friday, November 21, 2008, 11:16 AM Hi i have my repeater that is master 2 base repeater,,the oven as called. i wonder what is the simplest way to connect an uhf radio,Ge phoenix on her?? i could use the screew on her back plate?? i need an uhf that would be use as a link radio,anyone that want to use the Vhf repeater could enter via the uhf link radio. can it be done in a simplest way. i dont need cw id since i already have one on the vhf side so it would tx on uhf too. can you help me ?? thanks all gervais ve2ckn le bic,quebec _,_._,___
Re: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How???
Gervais, Here are the files I could not find to send you before.
73 - Jim W5ZIT
--- On Fri, 11/21/08, gervais fillion [EMAIL PROTECTED] wrote:
From: gervais fillion [EMAIL PROTECTED]
Subject: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How???
To: repeater-builder@yahoogroups.com
Date: Friday, November 21, 2008, 11:16 AM
Hi
i have my repeater that is master 2 base repeater,,the oven as called.
i wonder what is the simplest way to connect an uhf radio,Ge phoenix on her??
i could use the screew on her back plate??
i need an uhf that would be use as a link radio,anyone that want to use the Vhf
repeater could enter via the uhf link radio.
can it be done in a simplest way.
i dont need cw id since i already have one on the vhf side so it would tx on
uhf too.
can you help me ??
thanks all
gervais ve2ckn
le bic,quebec
,___
{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\fswiss\fcharset0 Arial;}}
\viewkind4\uc1\pard\f0\fs32 PSE508 Link Radio Interface\fs20\par
\par
\fs24 All connections to the link radio Interface may be taken from the GE Mastr II Control Shelf Mother Board screw terminals by making the following modifications to the PSE508 Board. Careful attention must be paid to avoid flowing solder on the pins of P1206B to avoid problems plugging the board into the card shelf. Solder to the inboard 1/16 inch of the pin only.\par
\par
Jumper Q6 Collector (3) to P1206B pin 6. This will be the RUS connection for keying the link radio. Q6 Collector goes negative for a valid received signal plus CTCSS tone. This will only provide a receive signal indication and key the link transmitter when a repeater user is keyed, and will not propigate the repeater ID or bubble up to the remote receiver. This signal would then be available on the Control Shelf terminal 10.\par
\par
Properly de-emphasized receive audio is present on the Test Header J6 pin 4 on the PSE508 board. This signal may be jumpered to P1206B pin 3 to make this signal available on the Control Shelf terminal 11. This audio is suitable for the Mic input on the link radio.\par
\par
Make the following connections from the Control Shelf terminals to the link radio Interface:\par
\par
2 - PTT\par
4 - MIC Audio\par
5 - GRD\par
9 - +10 VDC\par
10- RUS\par
11- REC Audio\par
\par
The circuit provides isolation for the audio path and the PTT path between the link radio and the repeater. The two should be grounded together and to a good earth ground external to the circuit before plugging in the interface.\par
\par
\fs20 W5ZIT [EMAIL PROTECTED]
}
PSE_MastrExec_Link.pdf
Description: Adobe PDF document
RE: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How???
I did not take any pictures Gervais, but the important thing to keep in mind is that the complete interface to the external radio can be done using the terminal connections on the rear of the card file. The modifications are only documented for a PSE-508, but the idea is there to use the two unused terminals on the card file for the receive audio and RUS signals by connecting them to the right pins in the repeater. Along with the existing mic terminals the interface board can then be remoted or placed in the link radio for a simple interconnect. 73 - Jim W5ZIT --- On Fri, 11/21/08, gervais fillion [EMAIL PROTECTED] wrote: From: gervais fillion [EMAIL PROTECTED] Subject: RE: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How??? To: repeater-builder@yahoogroups.com Date: Friday, November 21, 2008, 6:53 PM JIm these are great files for me and my project, by chance would you have some pictures of this board by chances?? Again you help is mostly appreciated by me thanks Gervais ve2ckn To: Repeater-Builder@ yahoogroups. com CC: [EMAIL PROTECTED] com From: [EMAIL PROTECTED] com Date: Fri, 21 Nov 2008 16:41:36 -0800 Subject: Re: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How??? Gervais, Here are the files I could not find to send you before. 73 - Jim W5ZIT --- On Fri, 11/21/08, gervais fillion [EMAIL PROTECTED] com wrote: From: gervais fillion [EMAIL PROTECTED] com Subject: [Repeater-Builder] Master 2 vhf and a link radio Uhf,How??? To: repeater-builder@ yahoogroups. com Date: Friday, November 21, 2008, 11:16 AM Hi i have my repeater that is master 2 base repeater,,the oven as called. i wonder what is the simplest way to connect an uhf radio,Ge phoenix on her?? i could use the screew on her back plate?? i need an uhf that would be use as a link radio,anyone that want to use the Vhf repeater could enter via the uhf link radio. can it be done in a simplest way. i dont need cw id since i already have one on the vhf side so it would tx on uhf too. can you help me ?? thanks all gervais ve2ckn le bic,quebec ,___
Re: [Repeater-Builder] GM-300 Repeater (was 900mhz , DTR, 906 to 923.75 MHz FHSS)
Andre, a pair of Motorola GM-300 radios can be interconnected as a repeater using a cable available on eBay for about 10 USD. I have used two radios set up like this, one as the receive and the other as the transmit and they worked just fine as a repeater. No squelch tail on the simple cable, but no problem getting them to work. The cable has a pot to set the repeated deviation, and that is the only adjustment required. 73 - Jim W5ZIT --- On Mon, 11/17/08, ANDRE [EMAIL PROTECTED] wrote: From: ANDRE [EMAIL PROTECTED] Subject: Re: [Repeater-Builder] 900mhz , DTR, 906 to 923.75 MHz FHSS To: Repeater-Builder@yahoogroups.com Date: Monday, November 17, 2008, 6:56 AM Benjamin, Do you know any brand, model? Thanks
Re: [Repeater-Builder] Need information for best radios to use for 9600 Baud and higher digital links
The Texas Packet Radio Society did a conversion for the RCA 500 UHF mobile radio for 9600 Baud packet back in the '80s. They had a very large network of radios covering most of Texas with the RCA radios used as the backbone. It was a pretty simple conversion as I recall, to do direct FM in the transmitter and recover the 9600 Baud data from the receiver. I don't know if any of the conversion info was ever on line, but a search of the TAPR site might find some of the info on that conversion. The big problem these days is that most of the radios were scrapped years ago and are no longer available. I have a buddy - N0IA (N0IA at WINLINK dot ORG) who converts the GE Rangr 440 radios for 9600 Baud operation, but I don't know how extensive the conversion is. It may involve changing out the receive filters to allow enough bandwidth to pass the 9600 Baud data. 73 - Jim W5ZIT --- On Sun, 11/9/08, K [EMAIL PROTECTED] wrote: From: K [EMAIL PROTECTED] Subject: [Repeater-Builder] Need information for best radios to use for 9600 Baud and higher digital links To: Repeater Builder Repeater-Builder@yahoogroups.com Date: Sunday, November 9, 2008, 7:40 PM Would like to hear from those that have converted OR can suggest a radio either 2m or 70cm that can do 9600 baud digital Packet. These will be put at remote hill tops to provide a backbone system for passing large volumes of data. I appreciate your time and trouble. Thank you 73 Kenny KG5KS DEC B AR _,___
