[Repeater-Builder] Re: 220 repeater
Yes, that's one of them. Darn thing only ran for 30 years before it broke. :) 'JK --- In Repeater-Builder@yahoogroups.com, n...@... wrote: At 1/2/2010 13:20, you wrote: G.E. pre-Prog. 'JK Is that 224.660 W6GAA on PV? Can't key it this evening. Bob NO6B
[Repeater-Builder] Re: 220 repeater
To follow up on Roger's 13-509 story, we built one also in the mid 70's and has been in continuous service in the Dallas area since, along with a pair of home built 224-JJ antennas (DB called them a 244 back then) - no duplexer (easy to do when you are on a 1500' tower). The radios may be hard to find but ask around, someone probably has a unit sitting in a closet. Mike/W5JR 1.1. Re: 220 repeater Posted by: w5rdwrwhitete...@verizon.net w5rdw Date: Sat Jan 2, 2010 5:23 am ((PST)) If you are interested in building it youself, a modified Clegg FM-76 or Midland 13-509 transceiver (xtal controlled rigs) can be modified very easily into a 220 repeater. I have done a number of repeaters like this, the first one in the late 1970's, into a very nice 10 watt repeater with a receiver that can't be beat as far as sensitivity is concerned. Very simple and reliable. Numerous articles on this modification are available on the web. Also available is the Maggiore repeaters line fromhttp://www.hiprorepeaters.com I have one of these on 224.18 MHz in Dallas and it has been trouble free many, many years. I have up at 350 ft. a dB224JJ antenna (no longer made) from dB Products (out of business, but a nice antenna). 73, Roger White W5RDW Murphy, Texas
[Repeater-Builder] Re: 220 repeater
If you are interested in building it youself, a modified Clegg FM-76 or Midland 13-509 transceiver (xtal controlled rigs) can be modified very easily into a 220 repeater. I have done a number of repeaters like this, the first one in the late 1970's, into a very nice 10 watt repeater with a receiver that can't be beat as far as sensitivity is concerned. Very simple and reliable. Numerous articles on this modification are available on the web. Also available is the Maggiore repeaters line from http://www.hiprorepeaters.com I have one of these on 224.18 MHz in Dallas and it has been trouble free many, many years. I have up at 350 ft. a dB224JJ antenna (no longer made) from dB Products (out of business, but a nice antenna). 73, Roger White W5RDW Murphy, Texas --- In Repeater-Builder@yahoogroups.com, Dan Blasberg ka8...@... wrote: All right folks, For those that run a 220 repeater, what are you running as far as the machine itself? A local group is looking to put a 220 MHz repeater on the air and would like some ideas. Thanks, Dan KA8YPY
Re: [Repeater-Builder] Re: 220 repeater
Two Alinco 220 mobiles work very well also. - Original Message - From: w5rdw To: Repeater-Builder@yahoogroups.com Sent: Saturday, January 02, 2010 7:18 AM Subject: [Repeater-Builder] Re: 220 repeater If you are interested in building it youself, a modified Clegg FM-76 or Midland 13-509 transceiver (xtal controlled rigs) can be modified very easily into a 220 repeater. I have done a number of repeaters like this, the first one in the late 1970's, into a very nice 10 watt repeater with a receiver that can't be beat as far as sensitivity is concerned. Very simple and reliable. Numerous articles on this modification are available on the web. Also available is the Maggiore repeaters line from http://www.hiprorepeaters.com I have one of these on 224.18 MHz in Dallas and it has been trouble free many, many years. I have up at 350 ft. a dB224JJ antenna (no longer made) from dB Products (out of business, but a nice antenna). 73, Roger White W5RDW Murphy, Texas --- In Repeater-Builder@yahoogroups.com, Dan Blasberg ka8...@... wrote: All right folks, For those that run a 220 repeater, what are you running as far as the machine itself? A local group is looking to put a 220 MHz repeater on the air and would like some ideas. Thanks, Dan KA8YPY
[Repeater-Builder] Re: 220 repeater
G.E. pre-Prog. 'JK --- In Repeater-Builder@yahoogroups.com, Dan Blasberg ka8...@... wrote: All right folks, For those that run a 220 repeater, what are you running as far as the machine itself? A local group is looking to put a 220 MHz repeater on the air and would like some ideas. Thanks, Dan KA8YPY
[Repeater-Builder] Re: 220 repeater
Re: 220 repeater So it look like the general recommendation is a converted GE or Micor. A lot of people mentioned using Hamtronics Modules if you plan to build your own from scratch. You might go back over the Group Posts starting around May through June of O9, you'll see posts I made regarding the complete construction of a number of 224 MHz Repeaters using the Hamtronics Modules. And some folks mentioned they were very happy with the performance of their turn-key Hamtronics Repeater. There is a folder in the Group Files Section with pictures of the first few repeaters I constructed. http://groups.yahoo.com/group/Repeater-Builder/photos/album/1157128983/pic/list That is kind of the direction I was leaning for the group. The GE and Micor Conversions are not to discounted. I suspect the end cost of doing a conversion would probably be a bit less than using new Hamtronics Modules. But you will need to find a radio and buy or build the modification (kit). I was initially worried the Hamtronics Receiver front-end wouldn't handle a busy mountain top location very well. But I was more than impressed with the receivers performance and red-hot sensitivity. One would expect the multi stage helical front end of the GE and Motorola receivers to better handle busy repeater site strong RF issues. But I have both commercial and home-brew 224 MHz repeaters operating on the same antenna system (yes, I have a 224 MHz antenna combiner system) and everyone of the installed boxes works very, very well. More options: I also bought and installed a Hi Pro 224 MHz RF Deck and I'm very happy with its performance. I had to rewire their factory repeater chassis to allow the use of a Com Spec TS-32 (which works just killer) and its been on the air ever since. http://www.hiprorepeaters.com/ As for conversions, what are folks using for final amps? A lot of the GE Micor Conversions replace the original PA with Hybrid RF Modules. The exciter (transmitter) puts out less than 1 watt in the typical conversion, which can be higher or even a fraction of (1 watt) depending on the radio used. The Hybrid RF Module resultant power output is normally between 10 to 20 watts depending on the module used and drive level. The Hamtronics transmitter puts out over 1 watt so I have used a number of different PA's... some of them shown in the pictures mentioned above. I just built a two-stage 224 MHz Amp and I'm getting about 35 watts output with the Hamtronics exciter drive level. I would say a lot of the choice will come down to how much money you want to spend. Building and aligning a solid state PA is not a recommended first time project for most people. There are not a lot of obvious choices for 224 MHz Repeater Amplifiers out there... but Hamtronics, TE (Southern Calif.), MFJ (Mirage) and a few other mfgrs make them available. What power level you have to drive an amplifier with will mean everything... You'll realize that as you move forward... Thanks, Dan KA8YPY Good luck in the contest... s.
[Repeater-Builder] Re: 220 repeater
DCFluX dcf...@... wrote: Spectra Engineering Party Ltd. MX-800 There were a number of 224 MHz PA's by the above mfgr offered and sold on Ebay a few years back. They were reported as failed or potentially as defective, but I couldn't get any of the ones I bought to die... wish the guy had more of them to sell. s.
Re: [Repeater-Builder] Re: 220 repeater
Has Alinco come out with a fix for the PL decoder yet? Mike At 05:32 AM 01/02/10, you wrote: Two Alinco 220 mobiles work very well also. - Original Message - From: mailto:rwhitete...@verizon.netw5rdw To: mailto:Repeater-Builder@yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Saturday, January 02, 2010 7:18 AM Subject: [Repeater-Builder] Re: 220 repeater If you are interested in building it youself, a modified Clegg FM-76 or Midland 13-509 transceiver (xtal controlled rigs) can be modified very easily into a 220 repeater. I have done a number of repeaters like this, the first one in the late 1970's, into a very nice 10 watt repeater with a receiver that can't be beat as far as sensitivity is concerned. Very simple and reliable. Numerous articles on this modification are available on the web. Also available is the Maggiore repeaters line from http://www.hiprorepeaters.comhttp://www.hiprorepeaters.com I have one of these on 224.18 MHz in Dallas and it has been trouble free many, many years. I have up at 350 ft. a dB224JJ antenna (no longer made) from dB Products (out of business, but a nice antenna). 73, Roger White W5RDW Murphy, Texas --- In mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com, Dan Blasberg ka8...@... wrote: All right folks, For those that run a 220 repeater, what are you running as far as the machine itself? A local group is looking to put a 220 MHz repeater on the air and would like some ideas. Thanks, Dan KA8YPY
Re: [Repeater-Builder] Re: 220 repeater
At 1/2/2010 17:26, you wrote: Has Alinco come out with a fix for the PL decoder yet? Mike IIRC the CTCSS decode function in the DR-x35 series radios is performed in the radio's CPU, hence it's not likely it will ever be fixed unless a revision is done to the CPU for new radios. Bob NO6B
Re: [Repeater-Builder] Re: 220 repeater
At 1/2/2010 13:20, you wrote: G.E. pre-Prog. 'JK Is that 224.660 W6GAA on PV? Can't key it this evening. Bob NO6B
RE: [Repeater-Builder] Re: 220 Repeater Power Amp
I second Skipp's motion, having been burned by Henry twice before, UHF amps delivered without a low pass filter, second harmonic about -40 dBc in the cell band... Also, TPL manufactures 220 amps (I had one, Adam N2ACF has it now), primarily for overseas markets. They use the same devices as in their UHF amps (MRF646's and MRF648's primarily). You'll probably have to call to find out availability in the US. --- Jeff Make sure you ask (at the time of the order) if the Amateur Band Amplifier you're buying includes the same type low pass filter supplied with the commercial RF deck. There's a historical reason why I make this comment... s. repeat...@... repeat...@... wrote: Henry Radio also makes 220 amplifiers. 1-800-877-7979 also give amateur discounts. Paul AA3VI No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.3/1970 - Release Date: 03/15/09 14:07:00
Re: [Repeater-Builder] Re: 220 Repeater Power Amp
I wouldn't waste any time or money on Henry or TE Systems repeater amplifiers. On my 220 repeater, I had the Henry and it was the biggest POS I had ever seen. The workmanship with regard to the soldering of components was terrible. I've used one on my 440 machine and it was worse! I have been using the TPL that I received from Jeff without any issues, keyed down for hours. Just looking at the PA board in the TPL versus the Henry is enough to tell you why the Henrys fail. Spend the extra money once, it will be well worth it. Adam N2ACF Jeff DePolo wrote: I second Skipp's motion, having been burned by Henry twice before, UHF amps delivered without a low pass filter, second harmonic about -40 dBc in the cell band... Also, TPL manufactures 220 amps (I had one, Adam N2ACF has it now), primarily for overseas markets. They use the same devices as in their UHF amps (MRF646's and MRF648's primarily). You'll probably have to call to find out availability in the US. --- Jeff Make sure you ask (at the time of the order) if the Amateur Band Amplifier you're buying includes the same type low pass filter supplied with the commercial RF deck. There's a historical reason why I make this comment... s. repeat...@... repeat...@... wrote: Henry Radio also makes 220 amplifiers. 1-800-877-7979 also give amateur discounts. Paul AA3VI No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.3/1970 - Release Date: 03/15/09 14:07:00 Yahoo! Groups Links
[Repeater-Builder] Re: 220 Repeater Power Amp
Make sure you ask (at the time of the order) if the Amateur Band Amplifier you're buying includes the same type low pass filter supplied with the commercial RF deck. There's a historical reason why I make this comment... s. repeat...@... repeat...@... wrote: Henry Radio also makes 220 amplifiers. 1-800-877-7979 also give amateur discounts. Paul AA3VI
RE: [Repeater-Builder] Re: 220 repeater antennas
Mike, I guess Jack made more than two, he still has two on his 500 foot tower with split TX and RX. Paul _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Mike - W5JR (f/k/a N5FL) Sent: Wednesday, December 05, 2007 9:33 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: 220 repeater antennas The person Paul refers to built 2 of these antennas, from scratch, (originally called a DB-244 by Decibel Products) for our group in the early 80's. The antennas are still in operation 1500' up the broadcast tower today, one used for RX and one used for TX - no duplexer. Performance remains superb. BTW, reflecting on a discussion about the Midland 13-509 radio for repeater operation, these antennas are connected to a split apart 13-509, built at the same time as the antennas. I know this is the kiss of death, but other than a run away crystal oven (it gets very cold at 1500' in an outdoor cabinet) the Midland repeater has had no failures after 25+ years of service. We keep intending to modify a hi-band GE MVP, but as long as the Midland keeps working, the project is low on the to-do list. I have one of the factory DB 220 antennas on the ground back in Texas, and will see it in a few weeks. I can take the measurements (unless someone else in DFW wants to do it) and a few pictures. If someone really really thinks they have to this one, I can be coaxed into selling it, local DFW pick-up only, I will not ship it. Mike / W5JR / Milton GA (a suburb of Alpharetta) Posted by: Paul Finch HYPERLINK mailto:[EMAIL PROTECTED]dpa [EMAIL PROTECTED] HYPERLINK http://profiles.yahoo.com/wb5idmwb5idm Tue Dec 4, 2007 9:07 pm (PST) I have a friend that has made his own 220 MHz version of the DB antenna, the worst problem he had was getting the harness to seal. I told him about Scotchkoat and he has not had a problem since. By the way, the Vapor Block coax does not do much for me. If the coax is sealed correctly you will never get water in it. All Vapor Block does is make it hard to work with, it still lets water migrate to the lowest point in the coax which is usually the Heliax connector. The problem with my friend right now is he is 76 years old and his mind seems to be going away. He was supposed to build me an antenna but has forgotten about it. The two antennas (1 TX, 1 RX) on his 500 foot tower have been up for about ten years with no problem. Paul HYPERLINK http://rover.ebay.com/rover/1/711-1751-2978-238/1?aid=10356774pid=2316294; REMEMBER - You can find it on ebaY No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.14/1171 - Release Date: 12/4/2007 7:31 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.15/1173 - Release Date: 12/5/2007 9:29 PM
Re: [Repeater-Builder] Re: 220 repeater antennas
[EMAIL PROTECTED] wrote: Actually, I was just offered the ACSSB equipment, including the combiner, if I take it all away. I can use the wattmeter units on the Telewave combiner, but don't know what I'd do with the rest of the stuff. Were the combiners isolator to mixer types? If so, you probably have some isolators with decent-sized loads on them that you can use on an Amateur system. If they were the type that uses cans, you have 220 cans... Either way, there would be plenty of usable things from a freebie like that. Nate WY0X
Re: [Repeater-Builder] Re: 220 repeater antennas
skipp025 wrote: So we agree... the Sinclair folded dipole antennas would be another great choice/option. Got any for sale...? :-) We're not selling ours! (GRIN) I read Skipp's stories of getting screwed a bit by Sinclair a while back and sure hoped it was just a temporary thing with the new manufacturing being in Mexico (something else Skipp found out during his unfortunate events). Sounds like it is. I hope. Skipp, I never asked you -- were you buying the VHF Heavy-Duty models or the non-HD when you had all the problems? Do you think it mattered? The club bought two VHF Sinclairs right around the time you were also having problems, and I'm trying to remember what your specific issues with them were. As far as I can tell, we haven't had any problems with either one. In fact, because of space limitations on a cross-arm, we bought a 2-bay for one of the VHF machines, and the silly thing outperforms a lot of other stuff at that site. (I'm still trying to figure that one out in my head/on paper. It's coverage went up, on a lower gain antenna system, and I haven't been able to figure it out in any modeling I've tried yet -- but I won't complain!) Nate WY0X
RE: [Repeater-Builder] Re: 220 repeater antennas
After spending so much time chasing the DB-224JJ information down I'd probably buy and use something else, which I have done. I'll keep the JJ Model in my mind as I pull down a few more of the Nationwide 220 ACSB Trunking Systems in the spring time. Knowing full well that Skipp may fight me on this recommendation, I'd lean toward a Sinclair SD214 or SD218 (big mama) dipole array. They're available in a split that covers 220. --- Jeff WN3A
RE: [Repeater-Builder] Re: 220 repeater antennas
Has anyone tried using the Austin antennas that were built for the 200Mhz ACSSB system on the ham band? There are several of them lying around on the ground here in Connecticut. Actually, I was just offered the ACSSB equipment, including the combiner, if I take it all away. I can use the wattmeter units on the Telewave combiner, but don't know what I'd do with the rest of the stuff. 73, Joe, K1ike -- Original message -- From: Jeff DePolo [EMAIL PROTECTED] After spending so much time chasing the DB-224JJ information down I'd probably buy and use something else, which I have done. I'll keep the JJ Model in my mind as I pull down a few more of the Nationwide 220 ACSB Trunking Systems in the spring time. Knowing full well that Skipp may fight me on this recommendation, I'd lean toward a Sinclair SD214 or SD218 (big mama) dipole array. They're available in a split that covers 220. --- Jeff WN3A ---BeginMessage--- After spending so much time chasing the DB-224JJ information down I'd probably buy and use something else, which I have done. I'll keep the JJ Model in my mind as I pull down a few more of the Nationwide 220 ACSB Trunking Systems in the spring time. Knowing full well that Skipp may fight me on this recommendation, I'd lean toward a Sinclair SD214 or SD218 (big mama) dipole array. They're available in a split that covers 220. --- Jeff WN3A ---End Message---
[Repeater-Builder] Re: 220 repeater antennas
The person Paul refers to built 2 of these antennas, from scratch, (originally called a DB-244 by Decibel Products) for our group in the early 80's. The antennas are still in operation 1500' up the broadcast tower today, one used for RX and one used for TX - no duplexer. Performance remains superb. BTW, reflecting on a discussion about the Midland 13-509 radio for repeater operation, these antennas are connected to a split apart 13-509, built at the same time as the antennas. I know this is the kiss of death, but other than a run away crystal oven (it gets very cold at 1500' in an outdoor cabinet) the Midland repeater has had no failures after 25+ years of service. We keep intending to modify a hi-band GE MVP, but as long as the Midland keeps working, the project is low on the to-do list. I have one of the factory DB 220 antennas on the ground back in Texas, and will see it in a few weeks. I can take the measurements (unless someone else in DFW wants to do it) and a few pictures. If someone really really thinks they have to this one, I can be coaxed into selling it, local DFW pick-up only, I will not ship it. Mike / W5JR / Milton GA (a suburb of Alpharetta) Posted by: Paul Finch mailto:[EMAIL PROTECTED] Re%3A%20220%20repeater%20antennas[EMAIL PROTECTED] http://profiles.yahoo.com/wb5idmwb5idm Tue Dec 4, 2007 9:07 pm (PST) I have a friend that has made his own 220 MHz version of the DB antenna, the worst problem he had was getting the harness to seal. I told him about Scotchkoat and he has not had a problem since. By the way, the Vapor Block coax does not do much for me. If the coax is sealed correctly you will never get water in it. All Vapor Block does is make it hard to work with, it still lets water migrate to the lowest point in the coax which is usually the Heliax connector. The problem with my friend right now is he is 76 years old and his mind seems to be going away. He was supposed to build me an antenna but has forgotten about it. The two antennas (1 TX, 1 RX) on his 500 foot tower have been up for about ten years with no problem. Paul
[Repeater-Builder] Re: 220 repeater antennas
Just off the phone with my inside contact at Andrew (Decibel)... as we all know now.. the DB-224JJ Antenna is long out of production. Their equiv replacement antenna is the DB-573EJJ fiberglass 3DB Unit with a list price of $2800.00 each. They don't seem to understand why (at the above bargain price) there have been 36 new antennas sitting in the Texas Warehouse for some time. go figure... I put the good word back in for the DB-224JJ but it looks like that model is lost in time. cheers, s. If ANYBODY has the data sheets that come in the box with a DB-224-JJ please send in scans of the sheets that were packed in the box (or snail-email a set of Xeroxes).
Re: [Repeater-Builder] Re: 220 repeater antennas
Hello Skipp As I have suggested before on this subject, it would seem to me that if someone would measure a DB224JJ very carefully and give us the dimensions of elements, spacing and harness most of us are capable of modifying a DB224 commercial model for 220Mhz. This would solve a problem. Thanks de Tom Manning, AF4UG - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 04, 2007 11:22 AM Subject: [Repeater-Builder] Re: 220 repeater antennas Just off the phone with my inside contact at Andrew (Decibel)... as we all know now.. the DB-224JJ Antenna is long out of production. Their equiv replacement antenna is the DB-573EJJ fiberglass 3DB Unit with a list price of $2800.00 each. They don't seem to understand why (at the above bargain price) there have been 36 new antennas sitting in the Texas Warehouse for some time. go figure... I put the good word back in for the DB-224JJ but it looks like that model is lost in time. cheers, s. If ANYBODY has the data sheets that come in the box with a DB-224-JJ please send in scans of the sheets that were packed in the box (or snail-email a set of Xeroxes).
[Repeater-Builder] Re: 220 repeater antennas
Hi Tom, You'd be almost home if you had that information. I know of no person who has properly cloned one of the famous DB-Products Vapour Block Cable Phasing harness assemblies for their multi dipole assemblies. Maybe someone on the group and I sure would like to hear (read actually) how their end product harness actually performed. I've got a few single high range 200 MHz DB Dipoles around... so the spacing and coax harness are the big beast. After spending so much time chasing the DB-224JJ information down I'd probably buy and use something else, which I have done. I'll keep the JJ Model in my mind as I pull down a few more of the Nationwide 220 ACSB Trunking Systems in the spring time. Since Hustler beefed up their 224 MHz G6/G7 Antenna I've had great results using them at repeater sites. No more birds peeling off the ground radials. cheers, skipp Tom Manning [EMAIL PROTECTED] wrote: Hello Skipp As I have suggested before on this subject, it would seem to me that if someone would measure a DB224JJ very carefully and give us the dimensions of elements, spacing and harness most of us are capable of modifying a DB224 commercial model for 220Mhz. This would solve a problem. Thanks de Tom Manning, AF4UG
RE: [Repeater-Builder] Re: 220 repeater antennas
I have a friend that has made his own 220 MHz version of the DB antenna, the worst problem he had was getting the harness to seal. I told him about Scotchkoat and he has not had a problem since. By the way, the Vapor Block coax does not do much for me. If the coax is sealed correctly you will never get water in it. All Vapor Block does is make it hard to work with, it still lets water migrate to the lowest point in the coax which is usually the Heliax connector. The problem with my friend right now is he is 76 years old and his mind seems to be going away. He was supposed to build me an antenna but has forgotten about it. The two antennas (1 TX, 1 RX) on his 500 foot tower have been up for about ten years with no problem. Paul -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of skipp025 Sent: Tuesday, December 04, 2007 10:47 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: 220 repeater antennas Hi Tom, You'd be almost home if you had that information. I know of no person who has properly cloned one of the famous DB-Products Vapour Block Cable Phasing harness assemblies for their multi dipole assemblies. Maybe someone on the group and I sure would like to hear (read actually) how their end product harness actually performed. I've got a few single high range 200 MHz DB Dipoles around... so the spacing and coax harness are the big beast. After spending so much time chasing the DB-224JJ information down I'd probably buy and use something else, which I have done. I'll keep the JJ Model in my mind as I pull down a few more of the Nationwide 220 ACSB Trunking Systems in the spring time. Since Hustler beefed up their 224 MHz G6/G7 Antenna I've had great results using them at repeater sites. No more birds peeling off the ground radials. cheers, skipp Tom Manning [EMAIL PROTECTED] wrote: Hello Skipp As I have suggested before on this subject, it would seem to me that if someone would measure a DB224JJ very carefully and give us the dimensions of elements, spacing and harness most of us are capable of modifying a DB224 commercial model for 220Mhz. This would solve a problem. Thanks de Tom Manning, AF4UG Yahoo! Groups Links No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.14/1171 - Release Date: 12/4/2007 7:31 PM No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.503 / Virus Database: 269.16.14/1171 - Release Date: 12/4/2007 7:31 PM Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 repeater antennas
--- In Repeater-Builder@yahoogroups.com, Robin Midgett [EMAIL PROTECTED] wrote: Obtain an old 224 cut it down by ~28%; that should drive it close to the 222 band. Has this been tried and does it work?? I'd be very suspicious about the harness coax lengths being correct without major renovation. They have to be *right*. Laryn K8TVZ
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/28/2007 08:19 AM, you wrote: Bob You seem to want to lump what is characteristically a complex impedance (R+or-jX) into a single number in order to simplify your argument that a non conducting RF output transistor is an open circuit because the transistor is not having any RF drive to the base (as in a class C amp with no current flowing in the collector / emitter circuit), and ignoring the Xc or XL remaining which will and is being transformed to an impedance different than the impedance originally designed to operate into as a load (50 ohms). Even then your argument again fails because the transformed complex impedance (+or-jX) will result in a source impedance from the transistor into something also complex, either capacitive or inductive, with little or no resistive component, and is never seen or sourced as a high impedance by any stretch of the imagination. I use the term high impedance loosely here to mean no resistive component, hence quasi-infinite VSWR, low return loss, mag. S11~=1 or however you want to put it. In reality, the impedance at the collector of the transistor is going to be pretty high. Yes it gets transformed around the Smith chart to a capacitance, through a short @ 1/4 wavelength, then inductive back to an open as you move away from it but I think that's irrelevent to this discussion. Why do you think that this (high impedance) is the case? Even in RF amplifiers operated as class A or AB, there is always current flow thru I'm talking about class C amplifiers, the ones normally found in repeater RFPAs. They draw no current when not TXing. Bob NO6B
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/28/2007 08:19 AM, you wrote: Bob You seem to want to lump what is characteristically a complex impedance (R+or-jX) into a single number in order to simplify your argument that a non conducting RF output transistor is an open circuit because the transistor is not having any RF drive to the base (as in a class C amp with no current flowing in the collector / emitter circuit), and ignoring the Xc or XL remaining which will and is being transformed to an impedance different than the impedance originally designed to operate into as a load (50 ohms). Even then your argument again fails because the transformed complex impedance (+or-jX) will result in a source impedance from the transistor into something also complex, either capacitive or inductive, with little or no resistive component, and is never seen or sourced as a high impedance by any stretch of the imagination. I use the term high impedance loosely here to mean no resistive component, hence quasi-infinite VSWR, low return loss, mag. S11~=1 or however you want to put it. In reality, the impedance at the collector of the transistor is going to be pretty high. Yes it gets transformed around the Smith chart to a capacitance, through a short @ 1/4 wavelength, then inductive back to an open as you move away from it but I think that's irrelevent to this discussion. Why do you think that this (high impedance) is the case? Even in RF amplifiers operated as class A or AB, there is always current flow thru I'm talking about class C amplifiers, the ones normally found in repeater RFPAs. They draw no current when not TXing. Bob NO6B
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Since when is the Xc of the Collector-Base capacitance of an output transistor or the Drain-Gate capacitance of a FET considered an open circuit at RF? Allan Crites WA9ZZU Jeff DePolo [EMAIL PROTECTED] wrote: Bypassing the relay shouldn't have an effect on the TX output Z when not TXing, as the final RF output transistor is going to look like an open too. Bob NO6B But the open transistors would be at a different electrical distance away from the duplexer than the open T/R relay was.
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/27/2007 13:30, you wrote: Since when is the Xc of the Collector-Base capacitance of an output transistor or the Drain-Gate capacitance of a FET considered an open circuit at RF? Allan Crites WA9ZZU OK, maybe not a million ohms but high enough compared to the nominal 1 ohm or so output Z of the transistor (remember that the output of these guys has to be transformed up from a very low impedance to 50 ohms because of the output power low voltage). Bob NO6B
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Bob Dengler wrote: At 2/23/2007 12:50 PM, you wrote: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) Hmmm, that sounds rather unusual. I can see the non-50 ohm impedance at the TX port pulling the notches on the RX side, but I wouldn't expect it to affect the much broader RX pass response to the point of degraded RX sensitivity. I'm assuming he had the antenna relay in line, and it was still switching when keyed/unkeyed. I would either hardwire the relay in tx mode, or jumper it out. -- Jim Barbour WD8CHL
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/26/2007 08:27 AM, you wrote: Bob Dengler wrote: At 2/23/2007 12:50 PM, you wrote: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) Hmmm, that sounds rather unusual. I can see the non-50 ohm impedance at the TX port pulling the notches on the RX side, but I wouldn't expect it to affect the much broader RX pass response to the point of degraded RX sensitivity. I'm assuming he had the antenna relay in line, and it was still switching when keyed/unkeyed. I would either hardwire the relay in tx mode, or jumper it out. Bypassing the relay shouldn't have an effect on the TX output Z when not TXing, as the final RF output transistor is going to look like an open too. Bob NO6B
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Bypassing the relay shouldn't have an effect on the TX output Z when not TXing, as the final RF output transistor is going to look like an open too. Bob NO6B But the open transistors would be at a different electrical distance away from the duplexer than the open T/R relay was.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? (Z-Matcher)
Keep in mind that a Z-Matcher in a GE radio has it's own test point to tune it, as do some other Z-Matchers. You don't need to use a wattmeter and worry about the line length. Chuck WB2EDV - Original Message - From: Mike Morris WA6ILQ To: Repeater-Builder@yahoogroups.com Sent: Saturday, February 24, 2007 2:53 AM Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? (Z-Matcher) At 10:19 PM 02/23/07, you wrote: In a message dated 2/23/2007 6:36:24 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: In regards to the question of a wattmeter adding length to a cable, in places where I use Z-matchers, I actually leave an N-barrel connector in line that can be removed for inserting the wattmeter without adding any cable. So when you put that barrel back, you're pretty darn close. ... Not necessarily. At low band VHF frequencies, you could probably discount the error produced by the Bird. But in high band VHF and up, it becomes progressively more critical. The constant is the physical length of the Bird line section which is 3 13/16 inches but including the terminating N connectors, the length is 5 1/8 inches. This is where it gets interesting. The line section is air line and has a different velocity constant than RG142 or RG214. Section 3-35 states: Using the THRULINE you will be inserting a 4 inch length of 50 ohm air line and the load on the transmitter will be changed from its original condition without the THRULINE. But Section 3-40 states: Since the length of line between a mismatched load and the source transforms the impedance of the load as seen at the source, line length now becomes critical. If the adjustments for maximum power transfer were made with the Model 43 in place, removing it shortens the line by four inches, plus two connectors. (emphasis mine). So one section says to allow 4 inches while the other section says to allow 5 1/8 inches. Go figure. In any event, the use of a single barrel would miss the mark at 2 meters and above. I read it as he opens up one of the male-to-barrel connections and inserts the combination of a Bird with the jumper cable that makes it plus the cable a half wave. This way nothing changes. Mike WA6ILQ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.446 / Virus Database: 268.18.3/699 - Release Date: 2/23/2007 1:26 PM
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Yes, and as the article referenced below points out, switching the UHF Mastr II to High Side Injection eliminates the problem. We originally thought that HSI eliminated the problem totally on 220, but it didn't, there is an overlapping range that one side or the other doesn't fix; that is what is referenced in the text below. Kevin mch wrote: Weren't there some 440 frequencies that had issues, too? Joe M. Kevin Custer wrote: I'm not Scott, but maybe I'll do... grin See Below Yes, there is sufficient isolation for single box conversion with absolutely no internal desense from the MASTR II Mobile, with the exception of the frequency ranges between 223T940/222R340 thru 224T060/222R460. Why don't these frequencies work? http://groups.yahoo.com/group/GE-MastrII/message/6972
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? (Z-Matcher)
[EMAIL PROTECTED] wrote: In a message dated 2/23/2007 6:36:24 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: In my most critical applications, I use permanent in-line Bird samplers. Then, cabling lengths don't change because I don't remove the samplers; and you know exactly what you have and where If you can afford to leave Bird 4275s in your cables, please be sure that my name is correctly spelled in your will. Actually, if you look on eBay, there are (still) deals on these type of things from time to time. I rarely buy anything like this new, because I don't have the largest budgets either, but, I will spend the money to be sure of things in critical applications. Here is one: http://www.kuggie.com/ahra/hmft.html http://www.kuggie.com/ahra/hmftinfo.html Kevin
[Repeater-Builder] Re: 220 repeater receiver recommendations? (Z-Matcher)
--- In Repeater-Builder@yahoogroups.com, Chuck Kelsey [EMAIL PROTECTED] wrote: Keep in mind that a Z-Matcher in a GE radio has it's own test point to tune it, as do some other Z-Matchers. True, there is a test point. And you can tune the two capacitors and stretch/squeeze the coil for a minimum as the instructions state. But I don't believe this is the best way. As Jeff WN3A and others have written, the best way is to monitor the output and current draw, tuning for maximum out along with minimum current. Best efficiency. By tuning this way, I've reduced current draw from 15.5 amps with the GE method to 12.5 amps, with the same PO. Laryn K8TVZ
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
I never suggested that the cable between the TX and the duplexer had to be an exact length and if the TX output is a true 50 ohms then any cable length produces no consequence at the cavity input. But if the TX impedance is not 50 ohms, I think any cable length other than half wave will make the cable a line transformer affecting the impedance presented to the cavity with a quarter wave producing the greatest impedance shift. That's not necessarily a bad thing because the impedance match of a random length cable is statistically as likely to improve the TX/cavity match as it is to degrade it. Exactly!!! Diddling around with this proved to be so frustrating that I eventually caved in and installed a Z-matcher at the TX output and tuned it for maximum cavity output at the pass frequency. It seemed (and seems) to me that this is a cleaner way to deal with the matching issue than trying to adjust BP/BR cavities with an input other than 50 ohms. If you want to use a Z-matcher to make your transmitter happy, you really need to monitor current draw when adjusting it in addition to power measurements. Just because you can install a Z-matcher and diddle with its caps to get a fraction of a dB more apparent power out doesn't indicate it's properly tuned. It could just be that the transmitter makes a little more power when looking into a load that's not 50 ohms, but at the possible expense of higher DC current draw, lower efficiency, and increased RF currents, all of which can be detrimental to the longevity of the PA. Also, apparent increases in TPO may be due to the generation of spurious products which are more likely when the transmitter is looking into a badly-matched load, which a Z-matcher is quite capable of creating. A spectrum analyzer would help tell the whole story (cleanliness is next to godliness when it comes to a mountaintop transmitter!). I'd rather see an isolator between the PA and duplexer, and if the PA is still not happy with that, fix/replace the PA. Also, when you're using a Z matcher at the output of the PA, the load Z (duplexer/feedline/antenna/etc.) is the other half of the equation. The Z of the antenna system is anything but constant. Electrical cable lengths (phase) vary with changes in temperature, thereby rotating the antenna feedpoint Z around the Smith chart. The antenna feedpoint Z is being transformed to some other Z at the end of the line, so the Z you are matching into is going to change as the electrical length of the line changes. As a practical example, a 200 foot length of Heliax on UHF has about a 20 degree phase change between 0 and 100 degrees F, and Heliax is much more phase-stable than most other cable types (especially solid polyethylene dielectric cables). The antenna feedpoint Z itself will also change with humidity/rain/icing, etc. Bottom line - matching to an antenna system is always unpredictable when done at the far end of the feedline. What looks good on the day you do the tuning may look ugly six months from now. It is for these reasons that I have always been against makeshift matching techinques, including cable length games, to make a system perform properly, for the performance improvements you think you're getting are likely to change due to factors you have little or no control over. I'd rather have everything on the ground kept as close to 50+j0 as possible, leaving only the antenna feedpoint Z as the variable you have no control over. And if the antenna Z is poor under normal weather conditions, it needs to be replaced. You mentioned that the power adjustment levels would not affect TX output significantly on an M II or Micor. I'm not familiar with the power control network they employ but does the collector voltage on the output devices remain constant during power changes? If not, how do you avoid significant output impedance shifts? On both M2 and Micor, the collector voltage of one of the early PA stages is varied to adjust the net gain (output) of the amplifier. The finals always have full 13.8V on the collectors (or emitters, in the case of PNP highband Micor transistors). --- Jeff
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Ken Harrison wrote: Thanks for the recommendation, Don. Though I'm sure a MastrII would be a great conversion for 220, we (in the group sense) want to try to save some of our money to get a remote base setup going on our repeater, too. Our small savings would be wiped out to replace the entire repeater, in spite of it being handy to have a complete spare should there be a problem in the future. Thanks, Ken Um-converting a MastrII or other commercial station is MUUCH cheaper then buying one of those made-for-ham pieces of junk. You'll spend $1000-1500 for a Maggiore/Kendecom/Spectrum, where you can convert an MII for a couple of hundred. -- Jim Barbour WD8CHL
[Repeater-Builder] Re: 220 repeater receiver recommendations?
Ken Harrison [EMAIL PROTECTED] wrote: Yes, I figured I might get a few different opinions. I certainly don't want to start a war, though! :-) Which is one of the reasons I tried to toss a one of everything type reply. The more information you have... the more choices you get to make. Regarding 3rd v. 5th overtone, no real reasoning there. Spectrum's current receiver is a 5th overtone. Our old one is a 3rd. (New crystal needed...) Depending on the receiver design... and your location.. you might have a problem receiving an image signal from the adjacent tv channel. The biggest sinner is probably the original Icom 3at portable radio. You can hear your repeater and the afternoon Soap Opera's at the same time. So the 5th overtone change/revision might be a method to avoid an IF Image or injection problem... but I don't yet know for sure. You're a little tuff to pin down on an opinion, though. I see you like Hamtronics well enough to try one of their synthesized models, you have a Hi Pro that keeps on playing like the energizer bunny, and you like Spectrum's audio interface. I also have a Spectrum Repeater in operation. Its had it's war stories but once I got them sorted out it's been playing well for a long time. Most of the grief has been the transmitter and their use of the wrong type (not rated for rf) capacitors in the rf chain. I changed them out and it's been rock and roll ever since. Haa. Are you a politician by chance? (snicker) Moderate republican on most issues... I'm not totally satisfied with customer service from Spectrum. The attitude presented was problematic, to be sure. Spectrum has done all they could to shoot their business in the foot. You'd think people would learn from their experiences or just go out of business. Somehow Spectrum keeps on ticking... I like to buy their tx/rx boxes at flea markets. Their basic design is pretty good and I have the docs on most of their stuff. So they can be a great deal in the right time and place. But there is so much used/surplus gear flooding the market right now that almost anything you buy should be a good deal. Anyway, we'll look at all the companies presented with an open mind and try to forget the bad incident we had with one of them. Thanks- Ken Group member and long time friend Eric bought the GE 220 conversion from the Repeater Builder (Scott/Kevin) Bunch at Dayton last year. He's been very happy with the results... so if you have a GE radio around that fits the conversion... it's a great way to go. We're still trying to get the braut smell out of the Dayton purchased surplus repeater gear. cheers, skipp
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Tks Bruce K7IJ In a message dated 2/22/2007 7:02:38 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: Ken, We not only do complete repeaters, we can custom build just about anything you want or need. We can simply build a rock-solid high-quality 220 receiver for you. We have done several receivers in the past that are rack mountable in a 2 unit rack space. I have a GE mastr II receiver that I am just finishing up. It came out looking so nice that I am going to take pictures as a show piece. Micor receivers would be VERY similar in construction. In my opinion, 2 things: 1. A Micor makes a much better repeater on 2M and 220 than a GE MII. (sorry GE loyalists!!) I think a Mastr II makes a much better repeater on UHF (sorry Micor loyalists!!) I would suggest a Micor for your 220 Machine. 2. If you're going to spend money on a new receiver, why not spend a bit more and get a completely new machine. Think about it, if your receiver is not 100%, what's saying that your transmitter is running at 100%? The notable thing about spectrum repeaters is that they lived up to their name, they took up the WHOLE spectrum. This might even be what is happing that you assume is a bad receiver. Instead of a bad receiver, you may have a spurious transmitter that is totally wiping your receiver off the map. Duplexers are meant to isolate, but there is only so much they can isolate. If you'd like a quote on a new machine or a quote for a new receiver, feel free to e-mail or call. Scott - Owner Repeater-Builder (the company) _www.repeater-www.repeaterwww.repeater_ (http://www.repeater-builder.com/custombuilt/) Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 - Original Message - From: _Ken Harrison_ (mailto:[EMAIL PROTECTED]) To: [EMAIL PROTECTED] (mailto:Repeater-Builder@yahoogroups.com) Sent: Thursday, February 22, 2007 8:39 PM Subject: [Repeater-Builder] Re: 220 repeater receiver recommendations? Thanks for the recommendation, Don. Though I'm sure a MastrII would be a great conversion for 220, we (in the group sense) want to try to save some of our money to get a remote base setup going on our repeater, too. Our small savings would be wiped out to replace the entire repeater, in spite of it being handy to have a complete spare should there be a problem in the future. Thanks, Ken --- In [EMAIL PROTECTED] (mailto:Repeater-Builder@yahoogroups.com) , Don KA9QJG [EMAIL PROTECTED] wrote: Ken first of All I noticed You stated Our group, so I would assume You have others kicking in to the Cost, I do not and I had Scott build Me up a 220 Repeater System, He did it in the process of Building a house and Moving All I had to do was Program the Controller, Hook up the Amp, Power Supply Duplexers, and Ant, I have never had any Problems for over a Yr. BRBRBR**BR AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com.
[Repeater-Builder] Re: 220 repeater receiver recommendations?
With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? Depends on the pa power level. You can easily test for desense both external and in cabinet. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? Depends a lot on the pa circuit, it's laytout and how you reduce the power output. If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? The practical answer... Again it depends on the above mentioned and how nit picky you are. Most people say the tx or pa to circulator cable length is not critical. I say it is for my own reasons and experience. Keep in mind you can easily match non 50 ohm outputs to 50 ohms using special coax values/lengths or various combos there of. 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? The answer you're probably looking for is yes... but again each case is specific to the respective hardware, circuit and all the related factors. An adjustable Circulator/Isolator is best setup under actual rf power... tracking generator will not often give the best adjustment... sometimes only close. Lunch hour... food... time to go, back later. cheers, skipp
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
[EMAIL PROTECTED] wrote: For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? At UHF-categorically yes, because both the MII and the Micor were avialable from the factory in full duplex versions for certain applications. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? It probably isn't exactly 50 ohms, but should be close. And the cables from the duplexer to the radio do NOT *REPEAT* NOT need to be an exact length. This again indicates an impedance mismatch in the duplexer and it should be retuned. (or a bad antenna/load) 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? No it should not. The load on the 3rd port of the isolator is still 50 ohms, so it should not be an issue. And I don't see the impedance of a good PA like an MII or Micor changing off of 50 ohms enough to matter. Other brands, who knows. -- Jim Barbour WD8CHL
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) The only problems we have had with in-cabinet de-sense go back to issues with a transmitter multiple getting into a sensitive spot of the receiver. This is a well known phenomenon on UHF Mastr II's, but it also happens on converted 220 micors and MII's. I have been wanting to write up this research for some time. I will try to do it as soon as I can. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? As others have stated, it may not be *exactly* 50j0, but it's close enough. Realize that most of the 50 ohm coax cable actually spec'd to be 52 ohm nominal!! I would think that the cable being 2 ohms off would be more detriment than the 50ohm designed output / input impedance that might move fractions of an ohm in impedance due to being tuned a few MHz from it's design frequency. If you want to get that picky, should a PA's output be tuned for 50 ohms when the frequency is changed from let's say 155.xx to 158.xxx? I would think that if the designers would have thought the port impedance to be that critical, they would have made provisions to adjust it. As far as our 220 modifications go; we use a M57774 power module. We DO NOT modify/retune the VHF pa to 220. If we did, we might run into design issues where impedance problems might rare their ugly head. We just use an off-the-shelf solution that works well. If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Can't say. I have no experience. I will defer this question to others. Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Rd Boswell, PA 15531 - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, February 23, 2007 2:24 PM Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Tks Bruce K7IJ In a message dated 2/22/2007 7:02:38 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: Ken, We not only do complete repeaters, we can custom build just about anything you want or need. We can simply build a rock-solid high-quality 220 receiver for you. We have done several receivers in the past that are rack mountable in a 2 unit rack space. I have a GE mastr II receiver that I am just finishing up. It came out looking so nice that I am going to take pictures as a show piece. Micor receivers would be VERY similar in construction. In my opinion, 2 things: 1. A Micor makes a much better repeater on 2M and 220 than a GE MII. (sorry GE loyalists!!) I think a Mastr II makes a much better repeater on UHF (sorry Micor loyalists!!) I would suggest a Micor for your 220 Machine. 2. If you're going to spend money on a new receiver, why not spend a bit more and get a completely new machine. Think about it, if your receiver is not 100%, what's saying that your transmitter is running at 100%? The notable thing about spectrum repeaters is that they lived up to their name, they took up the WHOLE spectrum. This might even be what is happing that you assume is a bad receiver. Instead of a bad receiver, you may have a spurious transmitter that is totally wiping your receiver off the map. Duplexers are meant to isolate, but there is only so much they can isolate. If you'd like a quote on a new machine or a quote for a new receiver, feel free
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
In a message dated 2/23/2007 12:00:13 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: It probably isn't exactly 50 ohms, but should be close. And the cables from the duplexer to the radio do NOT *REPEAT* NOT need to be an exact length. This again indicates an impedance mismatch in the duplexer and it should be retuned. (or a bad antenna/load) I never suggested that the cable between the TX and the duplexer had to be an exact length and if the TX output is a true 50 ohms then any cable length produces no consequence at the cavity input. But if the TX impedance is not 50 ohms, I think any cable length other than half wave will make the cable a line transformer affecting the impedance presented to the cavity with a quarter wave producing the greatest impedance shift. That's not necessarily a bad thing because the impedance match of a random length cable is statistically as likely to improve the TX/cavity match as it is to degrade it. Diddling around with this proved to be so frustrating that I eventually caved in and installed a Z-matcher at the TX output and tuned it for maximum cavity output at the pass frequency. It seemed (and seems) to me that this is a cleaner way to deal with the matching issue than trying to adjust BP/BR cavities with an input other than 50 ohms. You mentioned that the power adjustment levels would not affect TX output significantly on an M II or Micor. I'm not familiar with the power control network they employ but does the collector voltage on the output devices remain constant during power changes? If not, how do you avoid significant output impedance shifts? BRBRBR**BR AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
... but does the collector voltage on the output devices remain constant during power changes? If not, how do you avoid significant output impedance shifts? Yes. The final stages are kept at B+, the power set is done in the first stage in the PA; commonly known as the pre-driver or possibly pre-pre-driver stage. Using your logic, one could ask if a change in B+ voltage would skew the output impedance?? Say the difference between 11v and 15v (not ALL power supplies are created equal.) Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Rd Boswell, PA 15531 - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, February 23, 2007 4:06 PM Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? In a message dated 2/23/2007 12:00:13 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: It probably isn't exactly 50 ohms, but should be close. And the cables from the duplexer to the radio do NOT *REPEAT* NOT need to be an exact length. This again indicates an impedance mismatch in the duplexer and it should be retuned. (or a bad antenna/load) I never suggested that the cable between the TX and the duplexer had to be an exact length and if the TX output is a true 50 ohms then any cable length produces no consequence at the cavity input. But if the TX impedance is not 50 ohms, I think any cable length other than half wave will make the cable a line transformer affecting the impedance presented to the cavity with a quarter wave producing the greatest impedance shift. That's not necessarily a bad thing because the impedance match of a random length cable is statistically as likely to improve the TX/cavity match as it is to degrade it. Diddling around with this proved to be so frustrating that I eventually caved in and installed a Z-matcher at the TX output and tuned it for maximum cavity output at the pass frequency. It seemed (and seems) to me that this is a cleaner way to deal with the matching issue than trying to adjust BP/BR cavities with an input other than 50 ohms. You mentioned that the power adjustment levels would not affect TX output significantly on an M II or Micor. I'm not familiar with the power control network they employ but does the collector voltage on the output devices remain constant during power changes? If not, how do you avoid significant output impedance shifts? -- AOL now offers free email to everyone. Find out more about what's free from AOL at AOL.com. -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.441 / Virus Database: 268.18.3/699 - Release Date: 2/23/2007 1:26 PM
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/23/2007 12:50 PM, you wrote: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) Hmmm, that sounds rather unusual. I can see the non-50 ohm impedance at the TX port pulling the notches on the RX side, but I wouldn't expect it to affect the much broader RX pass response to the point of degraded RX sensitivity. I have experienced this phenomenon before, but without a duplexer (or anything except a load for the TX) connected to the radio. In my case it was due to leaking the RX RF from the signal generator (in this case just an HT) through the radio's case the RF taking different paths through the radio to the RX between the TX on TX off conditions. Sometimes the RX would degrade with the TX on (as expected), sometimes it would improve. Both conditions were eliminated when the sig. gen. was properly coupled to the RX's RF input. Bob NO6B
[Repeater-Builder] Re: 220 repeater receiver recommendations? (MVP?)
What about the GE MVP Scott..? Would the conversion be available and similar for the MVP Mobile? skipp Scott Zimmerman [EMAIL PROTECTED] wrote: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) The only problems we have had with in-cabinet de-sense go back to issues with a transmitter multiple getting into a sensitive spot of the receiver. This is a well known phenomenon on UHF Mastr II's, but it also happens on converted 220 micors and MII's. I have been wanting to write up this research for some time. I will try to do it as soon as I can. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? As others have stated, it may not be *exactly* 50j0, but it's close enough. Realize that most of the 50 ohm coax cable actually spec'd to be 52 ohm nominal!! I would think that the cable being 2 ohms off would be more detriment than the 50ohm designed output / input impedance that might move fractions of an ohm in impedance due to being tuned a few MHz from it's design frequency. If you want to get that picky, should a PA's output be tuned for 50 ohms when the frequency is changed from let's say 155.xx to 158.xxx? I would think that if the designers would have thought the port impedance to be that critical, they would have made provisions to adjust it. As far as our 220 modifications go; we use a M57774 power module. We DO NOT modify/retune the VHF pa to 220. If we did, we might run into design issues where impedance problems might rare their ugly head. We just use an off-the-shelf solution that works well. If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Can't say. I have no experience. I will defer this question to others. Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Rd Boswell, PA 15531 - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, February 23, 2007 2:24 PM Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Tks Bruce K7IJ In a message dated 2/22/2007 7:02:38 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: Ken, We not only do complete repeaters, we can custom build just about anything you want or need. We can simply build a rock-solid high-quality 220 receiver for you. We have done several receivers in the past that are rack mountable in a 2 unit rack space. I have a GE mastr II receiver that I am just finishing up. It came out looking so nice that I am going to take pictures as a show piece. Micor receivers would be VERY similar in construction. In my opinion, 2 things: 1. A Micor makes a much better repeater on 2M and 220 than a GE MII. (sorry GE loyalists!!) I think a Mastr II makes a much better repeater on UHF (sorry Micor loyalists!!) I would suggest a Micor for your 220 Machine. 2. If you're going to spend money on a new receiver, why not spend a bit more and get a completely new machine. Think about it, if your receiver is not 100%, what's saying that your transmitter is running at 100%? The notable thing about spectrum repeaters is that they lived up to their name, they took up the WHOLE spectrum. This might even be what is happing that you assume is a bad receiver. Instead of a bad receiver, you may have a spurious transmitter that is totally wiping your receiver off the map
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
A half wave length cable will act as an impedance transformer too. In this case it will be a 1:1 transformation and if the output of the transmitter is not 50 ohms then whatever impedance it is will be transformed to the cavity input. 73 Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Friday, February 23, 2007 4:06 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? In a message dated 2/23/2007 12:00:13 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: It probably isn't exactly 50 ohms, but should be close. And the cables from the duplexer to the radio do NOT *REPEAT* NOT need to be an exact length. This again indicates an impedance mismatch in the duplexer and it should be retuned. (or a bad antenna/load) I never suggested that the cable between the TX and the duplexer had to be an exact length and if the TX output is a true 50 ohms then any cable length produces no consequence at the cavity input. But if the TX impedance is not 50 ohms, I think any cable length other than half wave will make the cable a line transformer affecting the impedance presented to the cavity with a quarter wave producing the greatest impedance shift.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
I'm not Scott, but maybe I'll do... grin See Below [EMAIL PROTECTED] wrote: For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? Yes, there is sufficient isolation for single box conversion with absolutely no internal desense from the MASTR II Mobile, with the exception of the frequency ranges between 223T940/222R340 thru 224T060/222R460. Why don't these frequencies work? http://groups.yahoo.com/group/GE-MastrII/message/6972 I have built intermittent duty 2 meter repeaters from Mastr II and Micor Mobiles with 110 watt PA running at 140+ watts and have seen no sign of internal cabinet desense. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? We don't recommend operating a mobile conversion at greatly reduced power because the amplifiers are run in Class C, and reducing the power will generate spurious emissions. For the 220 conversion, we totally build a new power amplifier as seen in this Micor 220 conversion - GE is similar. See here: http://www.repeater-builder.com/pix/220micorpa.jpg http://www.repeater-builder.com/products/ampbd.html For other bands, we recommend the 45 watt version of the PA which will run rated power, continuously. 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Any time you convert commercial equipment to ham band operation, you likely won't have a perfect 50 ohm terminal impedance at the receiver or transmitter port, so yes, as all better repeaters builders know, the equipment might have to be tuned as a system using custom cabling lengths or Z Matchers for optimal performance. Kevin Custer Repeater Builder (the company)
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
In a message dated 2/23/2007 4:32:54 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: as all better repeaters builders know, the equipment might have to be tuned as a system using custom cabling lengths or Z Matchers for optimal performance. Can you comment on a difference of opinion regarding how a Z matcher should be adjusted? One school tunes for maximum smoke downstream of the cavities which is the approach I adopt. The other school tunes for minimum reflected SWR between the first cavity and the TX. My academic preference is for the latter, but as a practical matter it's a pain in the buns to do because you have to account for the line section that the Bird meter adds to the cable. Beyond that, using just a meter, what is it that is actually being measured since it could possibly be a composite of both on-channel energy and and off-channel reflected spurs and harmonics. BRBRBR**BR AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
[EMAIL PROTECTED] wrote: I'm particularly interested in any shortcomings of the G.E. that are not easily overcome. Repeatability of a band split conversion, out of band (high-band to 222) conversion, (where sensitivity is concerned) and tuning stability. It seems that *some* MASTR II receivers will come out better than others. You can have 3 like receivers in high-band with the same high-band sensitivity and tune them 2M and have 3 different sensitivity values. 220 is similar, some come out good, some don't. Anything can be made work if messed with long enough. You usually don't have to mess with the MICOR stuff much; it works equally well with each conversion. Very very few VHF MICOR receivers that work well originally don't convert well, 220 or otherwise. The UHF MICOR is a whole other story Here is an overview of my opinion. This is based on converting literally hundreds of receivers, MVP, MASTR II, EXEC II and MICOR: http://groups.yahoo.com/group/Repeater-Builder/message/49667 In my opinion, the only 'real' shortcoming of the GE receivers that isn't easily overcome is tuning stability due to their use of ceramic tuning capacitors. Kevin
RE: [Repeater-Builder] Re: 220 repeater receiver recommendations?
_ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Kevin Custer Sent: Friday, February 23, 2007 8:34 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? [EMAIL PROTECTED] wrote: In a message dated 2/23/2007 4:32:54 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: as all better repeaters builders know, the equipment might have to be tuned as a system using custom cabling lengths or Z Matchers for optimal performance. Can you comment on a difference of opinion regarding how a Z matcher should be adjusted? One school tunes for maximum smoke downstream of the cavities which is the approach I adopt. The other school tunes for minimum reflected SWR between the first cavity and the TX. My academic preference is for the latter, but as a practical matter it's a pain in the buns to do because you have to account for the line section that the Bird meter adds to the cable. Beyond that, using just a meter, what is it that is actually being measured since it could possibly be a composite of both on-channel energy and and off-channel reflected spurs and harmonics. I think you answered your own question, however I'll bite In *most* of the instances where I employed impedance matching between the transmitter and first cavity, the place where best return loss and least insertion loss was found, is very close to one another -tuning wise. I usually use the maximum smoke approach first and see what I have, then go from there. In my most critical applications, I use permanent in-line Bird samplers. Then, cabling lengths don't change because I don't remove the samplers; and you know exactly what you have and where Kevin Do you use a cable with the bird that makes it a ½ wavelength total line length when you insert it in line? That should not change things when the wattmeter/cable are removed. With a PA that does not exhibit a 50 ohm output I would think that it would be best to tune the Z match for maximum output looking at the antenna connection (output of the cavities). The reason being if you put the wattmeter between the Z match and the radio and tune the Z match for minimum reflected power as noted on the wattmeter then you are tuning the Z match to match the cavity input to 50 ohms that the wattmeter line section is setup for. But that is not what the transmitter really is so you end up with a flat reflected power between the cavity and the transmitter but it does not match the transmitter. 73 Gary K4FMX
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
Weren't there some 440 frequencies that had issues, too? Joe M. Kevin Custer wrote: I'm not Scott, but maybe I'll do... grin See Below Yes, there is sufficient isolation for single box conversion with absolutely no internal desense from the MASTR II Mobile, with the exception of the frequency ranges between 223T940/222R340 thru 224T060/222R460. Why don't these frequencies work? http://groups.yahoo.com/group/GE-MastrII/message/6972
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? (MVP?)
Yep, There are several conversions on the RB site for the MVP. They are loosely based on the MII conversions. I haven't done many MVP conversions of any particular band, but the ones I have done have not had any internal desense issues. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 - Original Message - From: skipp025 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, February 23, 2007 5:06 PM Subject: [Repeater-Builder] Re: 220 repeater receiver recommendations? (MVP?) What about the GE MVP Scott..? Would the conversion be available and similar for the MVP Mobile? skipp Scott Zimmerman [EMAIL PROTECTED] wrote: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? In my experience, yes. In fact, we have had several repeaters that the sensitivity actually gets BETTER with the transmitter active. (due to the correct 50 impedance being applied to the TX port of the duplexer) The only problems we have had with in-cabinet de-sense go back to issues with a transmitter multiple getting into a sensitive spot of the receiver. This is a well known phenomenon on UHF Mastr II's, but it also happens on converted 220 micors and MII's. I have been wanting to write up this research for some time. I will try to do it as soon as I can. 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? As others have stated, it may not be *exactly* 50j0, but it's close enough. Realize that most of the 50 ohm coax cable actually spec'd to be 52 ohm nominal!! I would think that the cable being 2 ohms off would be more detriment than the 50ohm designed output / input impedance that might move fractions of an ohm in impedance due to being tuned a few MHz from it's design frequency. If you want to get that picky, should a PA's output be tuned for 50 ohms when the frequency is changed from let's say 155.xx to 158.xxx? I would think that if the designers would have thought the port impedance to be that critical, they would have made provisions to adjust it. As far as our 220 modifications go; we use a M57774 power module. We DO NOT modify/retune the VHF pa to 220. If we did, we might run into design issues where impedance problems might rare their ugly head. We just use an off-the-shelf solution that works well. If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Can't say. I have no experience. I will defer this question to others. Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Rd Boswell, PA 15531 - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, February 23, 2007 2:24 PM Subject: Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? For Scott: With respect to using the GE MII mobile frame for repeater applications: 1. Can you say categorically that there is sufficient TX/RX shielding to prevent any desense at any power level the conversion is capable of operating? 2. When these converted mobiles operate with reduced TX power, what happens to the output impedance of the TX? Is it still 50 ohms? If not, does this affect the physical length of the half wave interconnect cables often suggested between the TX and an isolator and/or the cavities? 3. If the output of the TX is other than 50 ohms as a result of a power level change, does it upset the adjustment of the downstream isolator that has been tuned by a tracking generator? Tks Bruce K7IJ In a message dated 2/22/2007 7:02:38 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: Ken, We not only do complete repeaters, we can custom build just about anything you want or need. We can simply build a rock-solid high-quality 220 receiver for you. We have done several receivers in the past that are rack mountable in a 2 unit rack space. I have a GE mastr II receiver that I am just finishing up. It came out looking so nice that I am going to take pictures as a show piece. Micor receivers would be VERY similar in construction. In my opinion, 2 things: 1. A Micor makes a much better repeater on 2M and 220 than a GE MII. (sorry GE loyalists!!) I think a Mastr II makes a much better repeater on UHF (sorry Micor loyalists
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
In a message dated 2/23/2007 6:15:19 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: Do you use a cable with the bird that makes it a ½ wavelength total line length when you insert it in line? That should not change things when the wattmeter/cable are removed. I'm not sure I understand what you are saying. The Bird constitutes part of the line section and if you remove it after tuning with the z match, haven't you effectively changed the length of the line? BRBRBR**BR AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations? (Z-Matcher)
In a message dated 2/23/2007 6:36:24 P.M. Pacific Standard Time, [EMAIL PROTECTED] writes: In my most critical applications, I use permanent in-line Bird samplers. Then, cabling lengths don't change because I don't remove the samplers; and you know exactly what you have and where If you can afford to leave Bird 4275s in your cables, please be sure that my name is correctly spelled in your will. BRBRBR**BR AOL now offers free email to everyone. Find out more about what's free from AOL at http://www.aol.com.
[Repeater-Builder] Re: 220 repeater receiver recommendations?
Hi Ken, You're goint to get a lot of opinions regarding the quality of various receivers and a mention by a lot of sold customers to seriously consider using a converted commercial radio... the popular conversion being something like a GE or Motorola Radio. I'm not sure if I get the reason why you worry about using a 3rd or 5th overtone crystal in your receiver. Are you experiencing some issue with the injection scheme or an image from the adjacent TV Channel allocation? We've just had an Icom IC-RP2210 repeater receiver die and parts are no longer available. I've ordered a replacement R302-6 receiver from Hamtronics to drop into the box. I've heard a few negative reports about the Hamtronics Synth Equipment in the last few months but I'm willing to try one for myself. Since the repeater transmitter is still synth I wanted to allow the receiver to be reprogrammed when and where desired. I'm well willing to trust trying a Hamtronics Receiver because I've never really had a bad unit from them. Not only have I built and used a lot of Hamtronics gear.. but I've been using Jerry's vhf projects since the 1970's. My only beef would be to tell Jerry to get off the $%*(@ speaker phone when I call him. I bought a Hi Pro 220 repeater transmitter and receiver about two years back and it just keeps on playing rock solid. My only issue might be the whacky way Maggiore (and a lot other brands) treat (or doesn't treat) the receiver repeat audio. Seems like Spectrum has one of the better repeater receiver audio interface circuits. So read what other have to report... ask a lot more questions and get out your check book. cheers, skipp skipp025 at yahoo.com Ken Harrison [EMAIL PROTECTED] wrote: Our group is in need of replacing the receiver on our 220 box and I wanted to solicit some opinions from the group. Our current receiver is a Spectrum using 3rd overtone crystals. We are looking at the following: 1. Spectrum receiver using 5th overtone crystals. 2. Hamtronics R302 Synthesized receiver. http://www.hamtronics.com/r302.htm 3. Hamtronics R100 crystal receiver. http://www.hamtronics.com/r100.htm 4. Hi-Pro R4V http://www.hiprorepeaters.com/Receivers.htm What are you using and are you happy with it? Would you buy any particular one again? Why or why not. Thanks a bunch! Ken KE6N
[Repeater-Builder] Re: 220 repeater receiver recommendations?
Thanks for the recommendation, Don. Though I'm sure a MastrII would be a great conversion for 220, we (in the group sense) want to try to save some of our money to get a remote base setup going on our repeater, too. Our small savings would be wiped out to replace the entire repeater, in spite of it being handy to have a complete spare should there be a problem in the future. Thanks, Ken --- In Repeater-Builder@yahoogroups.com, Don KA9QJG [EMAIL PROTECTED] wrote: Ken first of All I noticed You stated Our group, so I would assume You have others kicking in to the Cost, I do not and I had Scott build Me up a 220 Repeater System, He did it in the process of Building a house and Moving All I had to do was Program the Controller, Hook up the Amp, Power Supply Duplexers, and Ant, I have never had any Problems for over a Yr.
Re: [Repeater-Builder] Re: 220 repeater receiver recommendations?
At 2/22/2007 19:01, you wrote: Ken, We not only do complete repeaters, we can custom build just about anything you want or need. We can simply build a rock-solid high-quality 220 receiver for you. We have done several receivers in the past that are rack mountable in a 2 unit rack space. I have a GE mastr II receiver that I am just finishing up. It came out looking so nice that I am going to take pictures as a show piece. Micor receivers would be VERY similar in construction. In my opinion, 2 things: 1. A Micor makes a much better repeater on 2M and 220 than a GE MII. (sorry GE loyalists!!) Interesting conclusion. Care to state any specific advantages the Micor has over the G.E.? I'm particularly interested in any shortcomings of the G.E. that are not easily overcome. Bob NO6B I think a Mastr II makes a much better repeater on UHF (sorry Micor loyalists!!) I would suggest a Micor for your 220 Machine. 2. If you're going to spend money on a new receiver, why not spend a bit more and get a completely new machine. Think about it, if your receiver is not 100%, what's saying that your transmitter is running at 100%? The notable thing about spectrum repeaters is that they lived up to their name, they took up the WHOLE spectrum. This might even be what is happing that you assume is a bad receiver. Instead of a bad receiver, you may have a spurious transmitter that is totally wiping your receiver off the map. Duplexers are meant to isolate, but there is only so much they can isolate. If you'd like a quote on a new machine or a quote for a new receiver, feel free to e-mail or call. Scott - Owner Repeater-Builder (the company) http://www.repeater-builder.com/custombuilt/www.repeater-builder.com/custombuilt/ Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 - Original Message - From: mailto:[EMAIL PROTECTED]Ken Harrison To: mailto:Repeater-Builder@yahoogroups.comRepeater-Builder@yahoogroups.com Sent: Thursday, February 22, 2007 8:39 PM Subject: [Repeater-Builder] Re: 220 repeater receiver recommendations? Thanks for the recommendation, Don. Though I'm sure a MastrII would be a great conversion for 220, we (in the group sense) want to try to save some of our money to get a remote base setup going on our repeater, too. Our small savings would be wiped out to replace the entire repeater, in spite of it being handy to have a complete spare should there be a problem in the future. Thanks, Ken --- In mailto:Repeater-Builder%40yahoogroups.comRepeater-Builder@yahoogroups.com, Don KA9QJG [EMAIL PROTECTED] wrote: Ken first of All I noticed You stated Our group, so I would assume You have others kicking in to the Cost, I do not and I had Scott build Me up a 220 Repeater System, He did it in the process of Building a house and Moving All I had to do was Program the Controller, Hook up the Amp, Power Supply Duplexers, and Ant, I have never had any Problems for over a Yr. -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.441 / Virus Database: 268.18.3/697 - Release Date: 2/22/2007 11:55 AM
[Repeater-Builder] RE: 220 repeater receiver recommendations?
My answer would be none of the above. Get a VHF micor and have Kevin do the 220 mod to it. I cannot imagine any of the receivers mentioned coming close to that in performance. Good luck, td wb6mie Our group is in need of replacing the receiver on our 220 box and I wanted to solicit some opinions from the group. _ Find what you need at prices youll love. Compare products and save at MSN® Shopping. http://shopping.msn.com/default/shp/?ptnrid=37,ptnrdata=24102tcode=T001MSN20A0701 Yahoo! Groups - Join or create groups, clubs, forums amp; communities. Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: mailto:[EMAIL PROTECTED] mailto:[EMAIL PROTECTED] * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups - Join or create groups, clubs, forums amp; communities. is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater Stuff
Jeff, Email me direct... I don't have your full email address and I'd like to talk about the 220 amp with you. thanks skipp skipp025 at yahoo.com [EMAIL PROTECTED] Jeff DePolo WN3A [EMAIL PROTECTED] wrote: I have a brand new TPL 100 watt continuous duty RXR series 220 amp available. I think it was around $850 or $900 new. I'd trade for a UHF amp of comparable quality and condition, 100 watts or more. I think I have a 4-cavity Wacom duplexer for 220 in storage too but I'd have to go digging to be sure. --- Jeff Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
The 13-509's are more common than you might think. I lot of them are popping up in estate sales and on E-Bay for well under $100. I've found half a dozen of them just this past year. If you just monitor one local 220 machine, buying one of these and ordering a crystal set for it is an inexpensive way to go. Don't forget that the Midland 13- 509, Clegg FM-76 and Cobra 200 were all the exact same 220 MHz radio marketed under three different names. Remember that you will have to re-crystal the rig for repeater use at some additional expense. Users are receive high and transmit low. You'll have to order crystals to convert to receive low and transmit high when acting as the repeater. I am currently building a machine using a 13-509 as an exciter and a 13-513 as a receiver. I find that the 13-513 220 synthesized model had a much better receiver. Steve K3PHL Philadelphia --- In Repeater-Builder@yahoogroups.com, no6b1 [EMAIL PROTECTED] wrote: --- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ [EMAIL PROTECTED] wrote: A properly converted commercial radio might be better in the end, but is a lot more work. Also true - but try and find a 13-509 these days. Back in the '80s there were many sources. These days the '509s are scarce, and Mitreks are common. You work with what you have or can get. Mike There's a Clegg FM-76 (same thing) on eBay right now (5745586858). Also a manual for same (5745122493). Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
--- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ [EMAIL PROTECTED] wrote: They were built as cheap as CBs of the era, and on the same production lines. But we hams built repeaters out of them because that's all there was. This may be all true, but the proven track record of every 13-509 repeater unmodified mobile radio I've worked with makes me conclude that they are perfectly acceptable for repeater use. I once tuned one up on a spectrum analyzer - couldn't make it go spurious even if I tried. I really, really suggest that you look at Mitreks and similar newer radios as 220 candidates. Kevin and Scott Z. have spent untold hours perfecting the 220 Micor and Mastr-II conversions and are GIVING AWAY their technology here. A properly converted commercial radio might be better in the end, but is a lot more work. Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
At 08:33 PM 1/20/05, you wrote: --- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ [EMAIL PROTECTED] wrote: They were built as cheap as CBs of the era, and on the same production lines. But we hams built repeaters out of them because that's all there was. This may be all true, but the proven track record of every 13-509 repeater unmodified mobile radio I've worked with makes me conclude that they are perfectly acceptable for repeater use. I once tuned one up on a spectrum analyzer - couldn't make it go spurious even if I tried. Absolutely true. I tried the same thing, and that is one reason that when Bill Pasternak came to me and asked for help on the book that I wasn't too worried about the 13-509 chapters. I really, really suggest that you look at Mitreks and similar newer radios as 220 candidates. Kevin and Scott Z. have spent untold hours perfecting the 220 Micor and Mastr-II conversions and are GIVING AWAY their technology here. A properly converted commercial radio might be better in the end, but is a lot more work. Also true - but try and find a 13-509 these days. Back in the '80s there were many sources. These days the '509s are scarce, and Mitreks are common. You work with what you have or can get. Mike Mike Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
--- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ [EMAIL PROTECTED] wrote: A properly converted commercial radio might be better in the end, but is a lot more work. Also true - but try and find a 13-509 these days. Back in the '80s there were many sources. These days the '509s are scarce, and Mitreks are common. You work with what you have or can get. Mike There's a Clegg FM-76 (same thing) on eBay right now (5745586858). Also a manual for same (5745122493). Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
thanks for the comments guys on PL encoding the old midlands. Its been a few years since I messed with them. Seems I remember I did something similar with cap/resistor tapped into it. Will have to dig them back up and see where I was trying to inject it. UHF 440 control/link pairs around here are drying up fast, so I thought I'd reuse these old radios and get some use out of them on 220 MHz. As for main repeater hardware on that band the club is just starting a GE M2 vhf to 220 conversion (w/non-pll exciter). 73's Ralph W4XE -Original Message- From: russ [mailto:[EMAIL PROTECTED] Sent: Wednesday, January 19, 2005 8:14 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater We use to tie them on to the wiper side for the dev. pot throught a 15 mfd bipolar cap. From what I remimber it worked ok. Good luck, Russ, W3CH Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: 220 Repeater
I added p/l to my 13-509 224Mhz repeater a couple of years ago. I just fed it into the mic input and it worked just fine for quite a while. When I got couple of kenwood TR742 radio's I ran into some problems where in the middle of a conversation they would just stop decoding the p/l tone. Some days it would work great and others it would cut out. So a couple of weeks ago I moved the p/l input and coupled it directly to the base of TR28 which is called the integrator. So far no problems with any of the user radios it seems to be working great. The p/l generator is a selectone ST-139 and my Tx audio is fed into the base of TR27 which I believe is called an active audio filter.. John Lock KF0M Wichita KS kf0m at arrl dot net -Original Message- From: Ralph Hogan [mailto:[EMAIL PROTECTED] Sent: Wednesday, January 19, 2005 7:28 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: 220 Repeater While we are on the subject of midland/clegg 13-509 radios/repeaters has anyone had luck PL'ing the exciter. It wasn't setup originally for PL encoders. Initial attempt exciter+PL audio wasn't very promising with a TS-32. Looks like you'd have to FM the varicap directly. Was going to use some I have as link radios and wanted to PL the link. tnx, Ralph W4XE Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater (squelch)
DCFluX [EMAIL PROTECTED] wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. If you use descriminator audio with some controllers, you can add an audio delay board and forget about squelch. The only problem might be the dmtf decoder falsing every so often on no-signal noise. (Depends on the type of dtmf decoder used). Not what I prefer or do myself, just a thought to throw out. cheers, skipp Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
Another option on the 13-509 (220mhz) or the 13-500 (2m) is to use the Link-Comm board that puts a Micor squelch on it. Look at my Mitrek Interfacing article at www.repeater-builder.com for info on that board, specifically http://www.repeater-builder.com/mitrek/mitrek-interfacing.html. The actual details are in the Carrier Squelch and in the Repeat Audio sections. Just take raw audio off the discriminator, run it through that board, and add the .01 cap to it to get de-emphasized audio (or leave it off to get flat audio). Mike WA6ILQ At 02:36 PM 1/18/05, you wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. On Tue, 18 Jan 2005 16:03:17 -0600, Paul Finch [EMAIL PROTECTED] wrote: I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
Our 220 repeater has been running a 13-509 receiver with an RLC-MOT on it for several years. We're extremely happy with it, although we're planning to convert to a Micor receiver some time soon. 73, Chris, KG0BP - Original Message - From: Mike Morris WA6ILQ [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 18, 2005 7:15 PM Subject: Re: [Repeater-Builder] Re: 220 Repeater Another option on the 13-509 (220mhz) or the 13-500 (2m) is to use the Link-Comm board that puts a Micor squelch on it. Look at my Mitrek Interfacing article at www.repeater-builder.com for info on that board, specifically http://www.repeater-builder.com/mitrek/mitrek-interfacing.html. The actual details are in the Carrier Squelch and in the Repeat Audio sections. Just take raw audio off the discriminator, run it through that board, and add the .01 cap to it to get de-emphasized audio (or leave it off to get flat audio). Mike WA6ILQ At 02:36 PM 1/18/05, you wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. On Tue, 18 Jan 2005 16:03:17 -0600, Paul Finch [EMAIL PROTECTED] wrote: I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
Mike, Do you still have the stuff you wrote on this radio and can you scan it? Can't seem to find The Book On Tue, 18 Jan 2005 19:33:24 -0600, Chris Peterson [EMAIL PROTECTED] wrote: Our 220 repeater has been running a 13-509 receiver with an RLC-MOT on it for several years. We're extremely happy with it, although we're planning to convert to a Micor receiver some time soon. 73, Chris, KG0BP - Original Message - From: Mike Morris WA6ILQ [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 18, 2005 7:15 PM Subject: Re: [Repeater-Builder] Re: 220 Repeater Another option on the 13-509 (220mhz) or the 13-500 (2m) is to use the Link-Comm board that puts a Micor squelch on it. Look at my Mitrek Interfacing article at www.repeater-builder.com for info on that board, specifically http://www.repeater-builder.com/mitrek/mitrek-interfacing.html. The actual details are in the Carrier Squelch and in the Repeat Audio sections. Just take raw audio off the discriminator, run it through that board, and add the .01 cap to it to get de-emphasized audio (or leave it off to get flat audio). Mike WA6ILQ At 02:36 PM 1/18/05, you wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. On Tue, 18 Jan 2005 16:03:17 -0600, Paul Finch [EMAIL PROTECTED] wrote: I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
--- In Repeater-Builder@yahoogroups.com, DCFluX [EMAIL PROTECTED] wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. One of the 2 13-509 repeaters I maintain was modified for flat audio (FM modulator, minimal processing). The other uses the stock phase modulator. I can't tell the difference between the two. They both sound good to me, but we had a problem with a 1.5 kHz rolloff at the discriminator. If you look at the schematic, you'll see a 1 K resistor on the discriminator output with a 0.1 uF cap to ground. My guess is that this was a poorly designed LPF to block the 455 kHz. We changed the .1 uF cap (C42) to .01 uF to fix this. As far as the squelch mod goes, here's what I have in my notes: C89: replace 4.7 uF with 1 uF or 0.33 uF (I think I used 1 uF; 0.33 uF made the squelch action a bit too choppy). C91: replace 4.7 uF with 0.47 uF Add a 1 megohm resistor between base of TR13 collector of TR14. This adds hysterisis which allows the squelch tail to be shorter without chopping, similar to how the G.E. MVP squelch works. I have the board layout scanned will try to post the 1 Mohm resistor location later. Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
A mod like this should be posted on to the repeater-builder web site. -- Original Message -- Received: Tue, 18 Jan 2005 10:23:44 PM CST From: no6b1 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: 220 Repeater --- In Repeater-Builder@yahoogroups.com, DCFluX [EMAIL PROTECTED] wrote: I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. One of the 2 13-509 repeaters I maintain was modified for flat audio (FM modulator, minimal processing). The other uses the stock phase modulator. I can't tell the difference between the two. They both sound good to me, but we had a problem with a 1.5 kHz rolloff at the discriminator. If you look at the schematic, you'll see a 1 K resistor on the discriminator output with a 0.1 uF cap to ground. My guess is that this was a poorly designed LPF to block the 455 kHz. We changed the .1 uF cap (C42) to .01 uF to fix this. As far as the squelch mod goes, here's what I have in my notes: C89: replace 4.7 uF with 1 uF or 0.33 uF (I think I used 1 uF; 0.33 uF made the squelch action a bit too choppy). C91: replace 4.7 uF with 0.47 uF Add a 1 megohm resistor between base of TR13 collector of TR14. This adds hysterisis which allows the squelch tail to be shorter without chopping, similar to how the G.E. MVP squelch works. I have the board layout scanned will try to post the 1 Mohm resistor location later. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: 220 Repeater
While we are on the subject of midland/clegg 13-509 radios/repeaters has anyone had luck PL'ing the exciter. It wasn't setup originally for PL encoders. Initial attempt exciter+PL audio wasn't very promising with a TS-32. Looks like you'd have to FM the varicap directly. Was going to use some I have as link radios and wanted to PL the link. tnx, Ralph W4XE Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
We use to tie them on to the wiper side for the dev. pot throught a 15 mfd bipolar cap. From what I remimber it worked ok. Good luck, Russ, W3CH - Original Message - From: Ralph Hogan [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, January 19, 2005 8:28 AM Subject: RE: [Repeater-Builder] Re: 220 Repeater While we are on the subject of midland/clegg 13-509 radios/repeaters has anyone had luck PL'ing the exciter. It wasn't setup originally for PL encoders. Initial attempt exciter+PL audio wasn't very promising with a TS-32. Looks like you'd have to FM the varicap directly. Was going to use some I have as link radios and wanted to PL the link. tnx, Ralph W4XE Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
I do not remember the value of the resistor... But I put my pl on the wiper of the deviation Pot worked for years.. I ran a 13-509 repeater in the 80's then got a Spectrum around 1989. and its still running... If I had to Build a machine today I would be running a Maggorie. as for the 13-509 I just recently tossed it into the trash.. the transmitter and amp stayed in the original case. and the receiver was placed into an RF box.. Neal-ka2caf Ralph Hogan wrote: While we are on the subject of midland/clegg 13-509 radios/repeaters has anyone had luck PL'ing the exciter. It wasn't setup originally for PL encoders. Initial attempt exciter+PL audio wasn't very promising with a TS-32. Looks like you'd have to FM the varicap directly. Was going to use some I have as link radios and wanted to PL the link. tnx, Ralph W4XE Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: 220 Repeater
Heard comments about the Maggiorie (probably mispelled) and such. Just yesterday I was at the KRXT tower in Rockdale Texas and lo and behold, a VHF Engineering 2M repeater - still ticking on 147.28. AF5C/R for the last 20 some odd years. Also, at my farm up in Gatesville, N5DDR/R on 146.96 still has the original Spectrum Communications with all the pretty lights and press buttons on the air. This is not to say they are the greatest, but by the same token, they are not the trash they are made out to be. Of course our local ham club, the Temple ARC with W5LM on 146.820 uses an Ericsson M3 with a TKR720 for backup. De NU5D Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: 220 Repeater
I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
I am intrested in the conversion procedure for the squelch, I am not happy with the audio quality of the midland as well. I was working on a new squelch board my self but too busy to sit down and build it then write the software. On Tue, 18 Jan 2005 16:03:17 -0600, Paul Finch [EMAIL PROTECTED] wrote: I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] Re: 220 Repeater
I'm setting up two of them as link radios for my 2-meter repeater. I also use a couple of them mobile to access my 220 repeater. Also loaned 3 of them to friends so they can use the repeater. They are inexpensive (if you can find them) and they still work fine! Lance WN0L - Original Message - From: Paul Finch [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 18, 2005 4:03 PM Subject: RE: [Repeater-Builder] Re: 220 Repeater I was wondering if anyone was still using one of those beasts, I am about to start my 220 project and that radio is probably the on I can have on the air the fastest. Paul WB5IDM -Original Message- From: Bob Dengler [mailto:[EMAIL PROTECTED] Sent: Tuesday, January 18, 2005 2:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: 220 Repeater At 1/17/2005 01:07 PM, you wrote: I was getting ready to split a Clegg FM-76. Basically identical to a Midland 13-509. Our club has 2 on the air now have performed well for over 25 years. Recently we did have one problem with one of the RXs: a cold solder joint on the 2nd LO (10.245 MHz) xtal. That's it. The 509's squelch leaves a bit to be desired. You can add a Micor squelch, or I have a mod to the existing squelch circuit (change 1 cap, add 1 resistor) that greatly shortens the tail (makes it sound like a G.E. MVP). Let me know if you need the latter. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
[Repeater-Builder] Re: 220 Repeater
Mike, I can give you a very positive reference for the repeater-builder 220 Micor conversions that Scott Z does. We purchased one for our 220 machine here in Philadelphia two years ago. We only had to go back to the site once within a few days to touch up centering the receive crystal which is normal for a first time implementation. Absolutely zero problems since. Very hot receiver and a good 25-30 watts out of the modified PA. They have certainly perfected the method. If you are in a low RF environment, I use the old Midland 13-513 (the synthesized model, NOT the crystal 509) as a repeater receiver on another one of my machines with very good sensitivity and overall results. I have also use the crystal 509 as a 1 watt exciter on the TX side. Steve K3PHL Philadelphia 224.180 PL 127.3 --- In Repeater-Builder@yahoogroups.com, k4ij [EMAIL PROTECTED] wrote: I am looking for a radio for my 220 repeater project. Just need the radio, have everything else. I would prefer something already on band. Something that is already converted is fine such as a Micor or Mastr II. If I don't find something I will do the conversion but want to check to see if someone might have one that would save some time. This will be used in a high RF enviroment and on a mountain top. If you have something drop me a line to: [EMAIL PROTECTED] 73 Mike K4IJ Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
