Re: [Repeater-Builder] Re: Frequency Change do I retune duplexer?
No Skipp, deviation was not mentioned, but the frequency change is on the same magnitude as increasing transmitter deviation - a 12.5 khz shift in frequency. 73, Steve NU5D skipp025 wrote: Steve S. Bosshard (NU5D) [EMAIL PROTECTED] wrote: I beg to differ on this one, most respectfully, but we are
Re: [Repeater-Builder] Re: Frequency Change do I retune duplexer?
The pad is only used during testing to isolate mismatch between the signal generator and spectrum analyzer and the device under test - not to be left in permanently. At WACOM it was standard practice to use a 10 dB pad between the test equipment and the device under test. This is because it is not a perfect world, and even top notch equipment may not be exactly what you expect - cheap insurance. 73. Steve NU5D [EMAIL PROTECTED] wrote: At 6/29/2008 22:57, you wrote: This is why it is best to put about 1-2 db 50 ohm pad between the duplexer and the receiver, to help keep the receive side at 50 ohm. And degrade my system sensitivity by that same amount? No thanks. The
Re: [Repeater-Builder] Who's fixing Service Monitors these days?
Ken did a nice rehab on my IFR500. http://www.kgelectronics.com/about.html Steve NU5D ka9qjg wrote: I really had Great Service from Bob at http://www.cardinalelec.com/ Fortunately it was only a Couple hour drive to drop it off and pick it up , This is where the Pros go for the FCC And Military Certification . Good Luck Don KA9QJG -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] isolator - circulator loss
Running 19 chs X 4 sites Simulcast / Voters - Already split antennas - 9 ch / 10 ch DB Spectra combiners - Still get around 37 watts after combining 100 watt station - The old DB CUBE was a little better on loss - would need another room for combining, though. Steve NU5D KF4TNP wrote: Jamey, Brent here, how you been? 10 channel system on 800mhz
Re: [Repeater-Builder] Re: Folded Diploles or Vertical antenna?
I beg to differ on the PEP vs Average in this instance. On an amplitude varying signal, PEP and AVERAGE are not the same (SSB or a complex amplitude modulating waveform). For FM, however, since FM has a constant amplitude signal, I believe PEP and Average will be the same. Once had a VHF Mastr Pro mobile showing well over 150 watts - a broken antenna connection and infinite (almost) SWR can make a meter read funny - also had a 450 IMTS mobile phone with a broken center conductor that had a very good SWR reading - just not much range - Your Mileage May Vary, and I may be wrong. 73, Steve NU5D Wayne wrote: Questions can arise here. First, what kind of wattmeter, with what accuracy level is he using. Is in an RMS or peak reading unit? Makes a difference. Where is he measuring the power. 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] noise on exposed folded dipole arrays and fiberglass encased antennas - YES !
A couple of observations: Same gain - same coverage. Fiberglass encased or exposed dipole - 5.8 dBd = 5.8 dBd - this is about the max you can expect from a 2M antenna before the law of diminishing returns kicks in. More Gain for BUCKS - look at a DB228 - 40 some odd ft long exposed dipole array and an offset pattern. Some of the numbers I have seen published for antennas are pure bull. Let the buyer be ware. My 30 years in LMR and lots of trips up the tower. Fiberglass encased antennas get blown to kingdom come more often than exposed dipole arrays. Exposed dipole arrays suffer loose hardware and noise when you run in duplex - learn about isolated TEEs and effective sensitivity before you go any further. Ron, N9EE makes a lot of sense on this one - easy to get to and change - use the diamond or comet job - also hustler. Nate hit the nail on the head about Height...Why have a 100 plus watt repeater in a non-voted system with 2 to 4 watt talkies trying to talk inDon't make much sense and won't buy you any coverage - now one way paging, or tall tower with split send and rec antennas and TTA - makes a whole new game plan. Best option - birds nest on the ground - find a tall building WITHOUT radio tenants - A congested site that cannot receive is close to useless unless you have a separate receive site, or voting receivers. You can also reach a point of diminishing returns on antenna height - remember 96.6 plus 20 times the common log of the distance in miles plus 20 times the common log of the frequency in Ghz will yield path loss. Start with a 4 watt talkie in the clear (deduct 20 dB for wearing the talkie on your belt in a car), and calculate to space loss, antenna gain, line and duplexer loss, and see how much over say -120 dBm actually gets to the receiver. Most receivers get 12 dB sinad at around 118 to 122 dBm at the antenna. Don't forget effective sensitivity - just because the receive can hear -119 from a generator don't mean the noise from a paging or fm broadcast station won't stifle the receiver. Also cavity filters don't necessarily block out of band signals. Anyhow, the point is that when the subscriber unit lacks enough RF to get to the receiver due to path loss, antenna height won't help. 50 ft - I would probably use 1/2 heliax, and first use whatever antenna I have laying around. If I have to reach in my pocket and buy the thing, then the $200 job looks pretty good (because at 50 ft it is easy to change out when it craps out) - Don't forget proper grounding, grounding kits on the transmission line, polyphasers, etc. Another thing - is the site in the middle of the desired coverage area ? If not, an offset pattern antenna may be in order (no need to pump signal into an area where there are no users. If the 50 ft tower is on a big mountain overlooking the town, then both an offset pattern AND depressed pattern may be in order. Anyhow that is how I would handle the question for my own use. As always I may be wrong, your mileage may vary, etc. Best 73, Steve NU5D skipp025 wrote: after our test here we found also that Fiberglass seems to catch static much more then metal antenna. Static is not exclusive to one type of antenna... I've had
Re: [Repeater-Builder] P25 (mis)Information?
On re-re-reading the post, I suspect the MA/COM salesman proposes just adding an analog trunked group to the system and calling that group talk-around. Just another group in the trunked system. Any group can be either Provoice (EDACS only) or P25 digital or Analog FM. To many folks in the land mobile business talk-around refers to simplex operation on the output frequency of a repeater station and operation independent of the repeater station. (hence my earlier post about collisions with trunked and simplex operations). From what I understand the problem with high noise environments and intelligibility is due to the characteristics of the DVSI IMBE vocoder and how this noise is treated in quantizing. Another talk group will not help in building coverage issues because the trunked system treats all groups alike unless a group by attributes is steered to one particular site in a multisite system. I am most familiar with simulcast. I believe the problems with P25 digital are exactly that and have nothing to do with brand or manufacturer. 73, Steve NU5D [EMAIL PROTECTED] wrote: Not wanting to start a flame war, but since I know there are some P25 gurus on here, I am posting this email exchange between an EDACS user and their local representative. Its rather self explanatory, I am looking for comments on the response; specifically, don't P25 radios have an analog mode? All (constructive) comments welcome.
Re: [Repeater-Builder] Re: P25 (mis)Information?
I believe there is more that just amplitude involved Dan. The vocoder coding algorithm handles sound patterns to (hopefully) improve intelligibility. I remember part of the selection of the IMBE vocoder dealt with voice inflection and the receiving station being able to discern subtleties in voice - fear - panic, or so I have heard. Of course I very well may be wrong. I do remember the old Secode consoles having compression and alc on the TX - not sure about receive - made the mechanical clock sound like a teletype machine next to the mic. Lets see, in 1995 were you referring to Motorola DES voice encryption as the digital communications system ? 73, Steve NU5D Dan Hancock wrote: I never cease to be amazed at how the simple answer to problems like this get overlooked. Give the FD /noise cancelling microphones. /The less background the mic picks up the less distortion problem there is. I've been on an 800 digital sytem for about 13 years now. Our earlier purchased radios came with noise cancelling mics, that later ones didn't. OMG what a difference. Some radios are so low in TX audio that even with the console volume at full you have trouble hearing the troopers. Then you get someone who's used to the noise cancelling mics using the non cancellers and they blow you out of the console. I guess the Motherola engineers never heard of ALC or the concept of using it on the console to keep audio levels even. Dan Hancock N8DJP
Re: [Repeater-Builder] Mastr II white noise on transmit
You could also turn the deviation pots - CG and Voice to min - not as solid as a ground on the input, but might help divide and conquer the noise source - I don't recall a M2 mobile making noise / hiss during TX. On a repeater station, a gate may be leaking causing some pass thru, but this would go away with a strong signal on the input. Steve NU5D Chuck Kelsey wrote: Tom - Let us know your results. Chuck WB2EDV - Original Message - From: Thomas Oliver [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, May 28, 2008 10:24 AM Subject: Re: [Repeater-Builder] Mastr II white noise on transmit I don't think there is anything connected to the CG HI input right now so I will give it a try. It is a Mastr II station.
Re: [Repeater-Builder] mice at repeater sights
The Later Mastr Pro GE series base stations used a slanted heat sink for the 12.6 and 10 V pass regulators. The chassis formed the back, and there was a cover on the front making a conduit for forced air from the 4 inch muffin fan. Poor field mouse got into the slanted heat sink, lost his grip, and went head first into the muffin fan - - did not decapitate but did trap him there and stall the fan - found the mummified remains some time later - then there are stories of a micor repeater loosing the 10 v return in the exciter - due to mouse urine destroying the trace on the PCB and various stories of stench. Best Memorial Day wishes to all, 73, Steve NU5D
Re: [Repeater-Builder] Re: mice and the trusty old GE Master Pro
Never fazed the Station - BTW, we are using some ultra sonic noise sources that plug into the AC outlets to deter rodents in our 911 center and some rural tx sites. Steve NU5D skipp025 wrote: Re: mice and the GE Master Pro What you didn't say was how the GE Master Pro in most typical cases probably kept working as normal. Hard as heck to kill a GE Master Pro I'd still have a number of them in service except I have to pay the site power bill and those tx strip tubes love to stay warm 24/7. The Master Pro Receivers are still very much killer good for current repeater projects. The front ends are very stout and the design is a well known solid peformer. I hate to see the receivers go in the dumpster... cheers, skipp
Re: [Repeater-Builder] IFR 1900 CSA
One of the few boxes that goes 1296 and beyond. Don't know how much support you can get from AEROFLEX or Cardinal Electronics. Nice box - is more a cell site test unit than a service monitor. I have both an 8921, 1900, and 120B. The 8921 rides with me all the time. Steve NU5D cruizzer77 wrote: I've been interested in a service monitor with spectrum and tracking for some time. Now I'd have the possibility to get an IFR 1900 CSA for $1200, the problem being that power meter and am modulation fail the self test. The plus points I see in this unit are that it's not too old and it seems to be a full-feature rig with nothing left to desire. I'd like to ask you the following: - Is there any hope to repair the non-working parts? - Does anyone have a service manual (maintenance manual) for it? These seem to be damn hard to track down. - Should I in general prefer this rig to a 8924C? Most other monitors including the 8920B (which seems to be an all-time favorite) are too expensive from the start. Of course this is a matter of personal opinion, but I'd like to hear your opinion. Thank you. Regards Martin Yahoo! Groups Links -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] OT Dayton Hamvention Group OT
http://groups.yahoo.com/group/hamvention/ MCH wrote: List NAME??? Joe M. 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/
Re: [Repeater-Builder] IFR 1600s
My 1900 has similar Tracking Generator Resolution. Low Resolution = Fastest Sweep - may pass over some stuff that would be displayed in HI RES that is a much slower sweep. I would expect some difference in the trace. Best success, Steve Bosshard NU5D Joel wrote: Hello Group Hope you'all may be able to help,my IFR 16006 is due for calibration but still passes all self test.The problem is in the trackin generator when tuning duplexer's it has three settings for the tracking gen, low, medium and high,I thought it was only susposed to just change the scan rate but it will show at different positions in low, medium and highmaybe http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] Cushman CE3
Seems like to OEM is Oven Air - I believe they are still in business. Steve NU5D n9wys wrote: If Tom needs a 5 MHz reference oscillator, they can be had for under $50 at www.alltronics.com... I picked one up to use as an HSO in an MSF5000
[Repeater-Builder] Angle Linear 3/31/08
I just received a note from Chip Angle that he will continue to provide preamps for the ham community. Filters and duplexers for amateur applications were taking a disproportionate amount of time and he is discontinuing that part of his business. 73, Steve NU5D
[Repeater-Builder] 24 vdc to 12 vdc smoke
The protection diode is typically across the power leads to the radio being protected (in parallel) , and not in series wit the radio because of both the forward drop of a silicon diode (around 0.7 V depending on the characteristics of the diode) , and the current carrying capability of the diode. The Cathode of the protection diode connects to A+. The Anode of the protection diode connects to - which when you use the bottom battery in a string of 2, 12 volt batteries is chassis / frame Ground. Much like a Zener that clamps -this clamping voltage is what a distinguishes a transorb from an ordinary protection diode. When both batteries are alive and well, the 2, 12 volt batteries in series form 24 volts which when applied through the solenoid, to the starter motor, and back to chassis form a complete circuit or loop. When someone forgets and leaves the radio turned on, connected across the bottom 12 volt battery and discharges the bottom battery, the top battery remains charged. The bottom or discharged battery is depleted and cannot power the radio or aid or oppose current through the starter motor. It is as though the bottom battery were removed. Now when the operator engages the starter motor, only the top battery has the potential to cause current to flow. This current flows from the + post of the top battery, thru the solenoid, thru the starter motor, thru the radio (the battery that the radio is connected across is dead and for all practical purposes does not exit) and completes the circuit at the - post of the top battery. (I don't want to start an electron current vs conventional current discussion). The starter will try and draw several hundred amps. The radio and protection diode can only handle maybe 20 amps, and then only for a brief period of time. If the radio is fused, the fuse should blow. If the radio is not fused, the radio will blow, because the current carrying capability of the protection diode is no match for the current carrying capability of a 24 volt starter motor and 500 mcm cable... I hope this makes sense, Dave, 73, Steve NU5D Dave Gomberg wrote: At 09:56 3/25/2008, Steve S. Bosshard (NU5D) wrote: Anyhow, without a fuse, the reverse protection diode or transorb in the radio tries to short and shunt the reverse current from the radio. So you are saying it is in parallel (and reverse direction), not series (in forward direction)?
Re: [Repeater-Builder] Re: 24 vdc to 12 vdc
I have installed land mobile stuff in Gov Surplus fire equipment, (right next to Fort Hood) and 24 volt Forestry Service and 24 V street sweeping equipment over the years. I will NOT install any equipment across one battery in a 24 V string. Take it somewhere else and let them do it. I will not. Without exception, from a RaVo street sweeper to a 2.25 ton truck, the driver will forget and leave the equipment turned on that is across the one battery resulting in that one battery going dead. Now picture this. 2 batteries in a string. One dead, one hot and healthy. Just for sake of discussion. lets say the radio / siren, stuff is across the bottom battery. Neg to GND, Positive to the Radio / Siren stuff AND the Negative of the second battery. Positive of the second battery to the starter solenoid, etc. As long as both batteries are charged this works GREAT. When the bottom battery is dead, and the top battery is OK, and the driver hits the Cole Hersey Switch and tries to crank the engine it is just as though the first battery was no longer there. Remember that the Positive of the bottom battery (now dead) is connected to the Negative if the second battery, thru the starter motor and back to ground. This effectively does 2 things. 1 - reverse polarity is applied to the dead battery and whatever equipment is hooked to it. 2 - The cranking current will be in excess of 400 amps. The fuse in the Neg side of the radio most likely won't make any difference because the case of the radio is tied to the chassis of the vehicle - ground. The fuse in the positive side (if present) may save the radio, but most often, the audio PA and RF PA are history as well as any protection diodes - 10 amp protection diode against 400 amp starter current - no contest. So, spring for the Astron or NewMar or whatever DC-DC converter - I like the fully isolated if possible or else I would encourage anyone to stay away from the one battery connection. Forklifts are even worse. Remember it is just a matter of time before stuff gets smoked... Steve NU5D School of Hard Knocks... Ron Wright wrote: Depending on the load connecting across one battery, the one connected to ground or the lower of the 2 12 batteries, will work. I would not do is load is heavy because I am sure the charging system is for both batteries and draining one much more than the other could upset things.
[Repeater-Builder] 24 vdc to 12vdc
Some of the earlier equipment with 24 volt power and tube radios did use a big ballast resistor. It did put out some heat. There was not that much difference in current draw between send and receive, so you might have 14 volts on receive and drop to 11 or so on send - with solid state the currents are much different - get a dc to dc converter. Some fire apparatus also had a separate battery and charging system for a water pump. We have connected radio equipment to the pump electrical system but the conductor runs were kinda long and lots of opportunities to pick up noise in the power system. Steve NU5D I know I could use a droping resistor but I can see it making a lot of heat
Re: [Repeater-Builder] Re: 24 vdc to 12 vdc
This assumes that the installer did not fuse the + lead to the radio. Normally a 25 to 35 watt radio has a 15 amp fuse but you might be surprised how many times the power cable has been cut and no fuse. Anyhow, without a fuse, the reverse protection diode or transorb in the radio tries to short and shunt the reverse current from the radio. Most of these can handle about 20 amps for a few seconds before the smoke gets out. Then the reverse protection diode is essentially gone and next in line us usually the audio power amp, and RF PA. While the radio tries to act like a short (for a few brief moments during cranking with the first battery dead the starter will draw hundreds of amps (or try to) thru the radio and protection diode. This doesn't continue very long at all. If the radio is properly fused, then the diode may short and blow the fuse, but without a fuse, the radio gets blown. Steve Dave Gomberg wrote: At 05:22 3/25/2008, Steve S. Bosshard (NU5D) wrote: any protection diodes - 10 amp protection diode against 400 amp starter current - no contest. Steve, this confuses the dickens out of me. I now understand the reverse polarity part, but won't the protection diode be reverse direction, and therefore the only relevant stat is the reverse voltage, 12v, and therefore presumably within ratings? I don't see what the current has to do with it because the diode will be non-conducting. The current rating is only for the conducting direction, right? (with one battery dead, the other battery will cause reverse current thru the first battery during cranking and at that time the protection diode will be briefly conducting). -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] Ritron RRX450 Manual
I have the 454 but no RRX - might try http://www.ritron.com and see if they will sell a manual ? Steve NU5D Jack Hayes wrote: I'm still searching for a manual (of copy) for a Ritron Patriot RRX450 UHF programmable repeater. Happy to pay copying costs and postage -- or whatever you like. Thanks,
Re: [Repeater-Builder] Tricks Tips to get a VHF Mastr III on 2M..
1 - Be sure it is working properly BEFORE you change anything. 2 - Program the new send and receive frequencies and adjust the VCO's if necessary. 3 - Align the receiver front end. An extender card really helps, but can be done without. I have tuned the front end looking at the IF out with a spectrum display unit. Last - go thru the factory alignment procedure at the back of the service manual and make sure the audio levels are set properly. Steve NU5D n2mci wrote: Are there any Tips Tricks to get a Mastr III rptr. on 2M? We have the transmitter working and the rec'er VCO, but the frontend is as fas as it goes but is still not enough.. About 1-1.5 uv sens. Thanks for any help.. -Pete N2MCI Yahoo! Groups Links
Re: [Repeater-Builder] Combination of Omni and Yagi antenna
Decibel Products called something similar a Keyhole Pattern array. (3 dB omni and 2, 3 ele yagis in VHF). Steve NU5D Camilo So wrote: Does any know is it possible to use two antenna with a matching line, I mean a G7 and a 12 element Yagi, on 220 MHZ, my G7 have a very good coverage in farther distance, but at a closer distance there is a dead spot due to tall building blocking on the way, but if I use the yagi pointed to that particular area, I have good signal, but to use a voting system It s going cost me a lot, I was thinking of using two antenna combination at the same time, The question now is how to calculate the exact length of the matching cable to go for 222.660 MHZ. any suggestion is highly appreciated. Thank You. de W4CSO http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] Astron RS-35M pass transistor Socket
Hi Vince, cannot help you with the socket - maybe Newark or Mouser, or such. I have seen folks actually solder to the leads on the pass transistor if all else fails. 73, Steve NU5D Vince Staffo wrote: My Astron RS-35M Power Supply has developed a problem with one of the sockets used for the TO-3 Pass Transistors. The Astron supplied socket does not look like it is very good quality. Does anyone know of a better replacemnt socket that I could use? If so please provide part number and where to order if possible. Thank You, Vince WB2FYZ begin:vcard fn:Steve Bosshard n:Bosshard;Steve org:Bosshard Radio Service adr:;;503 B. South 25th. Street;Temple;Texas;76504;USA email;internet:[EMAIL PROTECTED] tel;work:254-773-1102 tel;fax:254-773-1174 tel;home:254-770-0111 tel;cell:254-624-4230 url:http://www.bosshardradio.com version:2.1 end:vcard
Re: [Repeater-Builder] Unknown board
Seems like the chips are switched capacitance audio filters - similar used in packet tone encoder / decoder. Don't have a clue. Steve jeffcarlyle wrote: Hi all, I posted 4 pics in the photo section of a board I got in a lot
Re: [Repeater-Builder] Unidentified Tone Board
You can probably get the truth chart from a Maxon LMR or Selectone LMR service manual - The MXCOM chip was not uncommon for them - will take a peek in the morning. Steve NU5D Terry wrote: Can anyone ID this tone encoder board? IC is mx-com mx315 marked with FT303 6 dip switches DCS / PL ? Truth Chart ? THX, WX3M -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital
Re: [Repeater-Builder] Community Repeater War Stories
Amen on the LTR trunk. Worst problem was an electrical contractor and a materials hauler. The haul guy had instructions to report to base when he reached the gravel pits. This is unit 10, I am at the gravel pit, where do you want me to go from here? Poor gravel hauler's loudspeaker went open. He called in every 5 minutes for the next hour or so, while the electricians were dispatching calls - took a 12 pack of Bud to calm that one down. Steve NU5D skipp025 wrote: Ahh... that magic Busy Channel Lock-out feature that never
Re: [Repeater-Builder] 1272 Mhz Preamp
I have used many of the ARR preamps. They are great. They do not have a product in the 1200 Mhz band. Also I cannot find a cross band coupler other that a Diamond MX37 or possibly a Comet product. I was hoping some folks here tried something beside 2M and 70 CM. Thanks for your reply, James and VY 73, Steve NU5D James Delancy wrote: I am personally a big fan of Advanced Receiver Research (Burlington, CT). I just ordered 3 different pre-amps from them and had them in a few days. James
Re: [Repeater-Builder] feedline advice
Ditto on the super flex - or 1/2 heliax. de nu5d Jay Urish wrote: Just go get some 1/2 suplerflex and call it good. Willis M. Hagler wrote: Hello All, I am putting up a UHF repeater in Seattle and have a question regarding feedline losses. The repeater site is on top of a /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital
Re: [Repeater-Builder] Re: Matching a 75 ohm antenna
I had some very nice 3/4 catv 75 ohm line some years ago. It was foam dielectric with a jelly filled outer jacket - nice stuff. I took a hack saw and split the outer shield kind of like peeling a banana, then cleaned out the dielectric, and took a small hammer and drove a PL258 over the center pin after using a small amount of passivating compound on both the center conductor and the outside of the PL258. Then I took a small stainless steel water hose clamp to secure the shield, and skotch coated and taped the mess. I used this line on a 150 ft water tank UHF repeater behind the MW Cafe / City of Harker Heights, Texas water tank for over 10 years. The standing wave was not perfect, but the system - UHF Pro with a Wacom Duplexer and ARR Preamp worked very well for many years, until the City decided to de-commission the water tank. Also I used water hose clamps to attach grounding braid top and bottom - again skotch coat and tape and noalox compound sparingly applied. Yep, its better to match impedances, and it makes it easier to avoid desense when you do things 'right', but in reality, I doubt you will see much difference one way or the other - your mileage may vary - back to bed with visions of left over of sugar plumbs going through my head, etc. Steve NU5D [EMAIL PROTECTED] wrote: At 12/23/2007 23:52, you wrote: Bob, those 1/12 wave lenths are prety short, I figuerd (in my head)
Re: [Repeater-Builder] Sinclair Q202G duplexer Conversion
When I moved some 155 mhz duplexers to 146 I found adding a type n elbow in places where I could not get the notch to move made just enough difference. This adds about an inch without having to rebuild the harness, or else a nice way to test cable lengths. Also if adding the elbow makes things worse, then you might want to cut and try. 73, Steve NU5D Eric Lemmon wrote: Bill, This topic has been addressed several times in recent years. There is no formula for the harness; Sinclair makes two harnesses, one with 12
Re: [Repeater-Builder] RF Guys Chip Programmer problem
Which radio and which chip - Xicor 2212 and 9346 are pretty simple. Others are not as common. Steve NU5D PS - 2212 is a parallel eeprom and 9346 is a serial eeprom. Neither has links to burn. 2764s ? are different. steve w4wsm wrote: Just got a programmer to burn GE chips. I've tried it on 4 different computers now and all kinds of printer port settings. It will act like it is burning but when I verify it just shows errors. Put the chip
Re: [Repeater-Builder] Zetron model 48 controller
http://www.zetron.com/data/site/templates/zetrontemplate.asp?area_0=pages/menus/privateradioprodarea_1=pages/products/privateradio/m48-max http://tinyurl.com/yva5pd R.Wesley Bazell Jr wrote: Picked up this Model at fort Wayne Hamfest for my MastrII 440 Repeater. Have been using Software with computer for ID up till now. See no info on Repeater tech website on this Zetron. anyone know how to program the Eproms on this unit. Have I bought an White Elephant? -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital
Re: [Repeater-Builder] Re: AM interference on long cable run
Both ends need an isolation transformer and both send and receive audio. Also if there is a high Z circuit, you may try adding a 1K or so shunt resistor to lower the impedance of the circuit. I would experiment with grounding only one end of the cable at first. Of course this is moot with the cable severed by the mower, but there is no reason the circuit should not work. Also the .001 line to line and line to ground may help. We had music on hold from an AM broadcast station into a telephone patch years ago, and the .001 capacitors fixed that particular problem. Best luck, Steve NU5D Jim Brown wrote: Skip, I did have transformer coupling on the audio lines out at the repeater with both sides of the twisted pair isolated from ground, but did not try putting transformers in the line back at the computer. -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital
Re: [Repeater-Builder] AM interference on long cable run (was PSE-508-2 Repeater Controller for Mastr II Station)
I have had good luck with k-comm line filters. First would try 0.001 mf line to line and line to ground - on the audio pairs - be sure you are using balanced pairs and not grounded single ended lines. This may mean adding a 600 ohm 1:1 transformer at each end. Also 1/4w 100 ohm resistors and movs make great line protection for lightning mitigation. 73, Steve NU5D Mike Morris WA6ILQ wrote: At 05:58 AM 11/21/07, you wrote: (big chunk cut out) Al published my EchoLink interface on his web site
Re: [Repeater-Builder] Re: Ailing Wacom 220Mhz Duplexer
See if the screw in side connecting pin on the TEE is loose - glad you found it. I have had a type N tee with a loose connection where the side pin screws into the other pin. sb Keith, KB7M wrote: Just an update on the status of this project. I thought what I've found might be interesting to the group. At the suggestion of a group member, I removed the top and side ports to the cavity. It turns out that this is quite easy to do. You just remove the three screws holding the top port, and the nut holding the side port. At this point the whole assembly lifts out easily. I inspected the assembly and could see no problems. I resoldered the
Re: [Repeater-Builder] A couple of questions
Be very sure the repeater is working properly BEFORE you re-crystal and re-tune. This is probably old hat for you, but I have seen many problems in recrystalling an unknown status station. Steve NU5D Ron Wright wrote: Joe, I order a number of crystals each month and use Bomar. I also like International, but have had delivery problems with them. However, both make an excellent crystal. Bomar has min of $50 so if get only a pair then $25 each with 1 week delivery. If order 4 or more can get for $15 each with 2 weeks, $10 for 3-4 weeks. International is I think $19.95 for 2 weeks, but not sure if they will make it. It's been a while. All you need is freq, model (GE mastr II), where to ship to and method of payment. Both take credit cards. On the radio for remote base cannot comment. 73, ron, n9ee/r From: Joe Landers [EMAIL PROTECTED] Date: 2007/11/19 Mon PM 04:45:20 CST To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] A couple of questions Hey everyone I want to ask a couple of questions and see if I get any replies I am getting ready to change a frequency in a mastr II and I got to buy some crystals Who is doing the best job at a resonable rate with them nowadays . Secondly I have a radio I want to use for remote base use I need a mike plug diagram of pinout diagram to make a jack for the controller The radio info is as follows it is a maxon model 1520a mobile plate on back has p/n 717810 no serial number Thanks everyone have a great holiday Michael J. Landers Assistant Emergency Radio Officer Chesterfield County Virginia. Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Yahoo! Groups Links -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital/
[Repeater-Builder] Wide Area Coverage
Imagine your 2M or 70CM base station were on a tall, tall, tower and you can key and operate any one of 140 different repeaters world wide, no noise, static, etc. Thats DSTAR today. From Hawaii to Alaska, to Vancouver to Ottawa, to Los Angeles, to London, to Berlin to Venice, to Darwin, AU. Today and NOW. I know this is probably a bit off topic, and I appreciate your indulgence. visit www.dstarusers.org and see who's talking. Steve NU5D, /K5CTX B Temple, Texas US -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] MSR2000 info
http://www.batlabs.com/models.html Jim wrote: Ron Wright, Skywarn Coodinator wrote: hi all, Anyone know details of a MSR2000 with part number C73GSB-3145B. -- /Subscribe to dstar_digital/ Powered by groups.yahoo.com http://groups.yahoo.com/group/dstar_digital
Re: [Repeater-Builder] Installation of Radio Equipment in Elevator Machine Rooms and Hoistways
In Texas the JCAH (Joint Commission on Accreditation of Hospitals) guidelines forbids installation and operation of radio transmitting equipment in hospital elevator equipment rooms. Both Scott and White and Kings Daughters Hospitals had us re-locate all of their radio equipment in the early 90s.. Coaxial cables still run through the elevator rooms, but there is no radio equipment installed therin. As earlier stated graphite from the motor brushes along with noise from relay contactors and now SCR/Triac control is not nice to say nothing of the ambient noise in the rooms - had to wear headphones to hear a receiver, make such installations unpleasant at best. I believe the reasoning was RF emissions possibly affecting elevator controls. Steve NU5D Nate Duehr wrote: On Oct 31, 2007, at 10:29 PM, Eric Lemmon wrote: to go. If I remember correctly, the issue was resolved by erecting a fireproof (cinder block) wall to separate the radio equipment from the elevator machine room, in essence creating a new room with a separate
Re: [Repeater-Builder] Re: duplexer isolation and reciev
Even magnetic amplifiers and tunnel diodes.. [EMAIL PROTECTED] wrote: At 10/24/2007 19:26, you wrote: I would consider anything that uses a semi-condutor material to be active, Silicon and Germanium transistors included. According to Wikipedia, a passive device is a device that is not capable of power gain. If it is capable of power gain, it is an active device. If needed, I can probably dig up some definition in an IEEE reference that essentially says the same thing. Bob NO6B
Re: [Repeater-Builder] Re: duplexer isolation and receiver noise bud
Can't an isolator do both, provide a constant 50 Ohm load to the transmitter, and offer 30 (single junction) to 60 (dual junction) of isolation from signals travelling from the antenna to the transmitter for mixing. If isolators were just to provide a constant load, why are there dual junction isolators ? Steve NU5D The primary reason for a isolator is to prevent intermod I strongly disagree... An isolators main purpose is to prevent a power amplifier from burning up due to excessive reflected power; due to antenna system issues. http://groups.yahoo.com/group/dstar_digital/
Re: [Repeater-Builder] Re: duplexer isolation and reciever n
Wonder if any of these here diodes 'tunnel' ? Steve NU5D Jeff DePolo wrote:
Re: [Repeater-Builder] duplexer isolation and reciever noise budget
If this is going mobile on a 40 ft crank up I would sure consider separate antennas is possible. You can get into some real challenges, and even with separate antennas you will still have issues to consider. Also you will have a much better idea when the repeater pair is determined. Steve NU5D Gary Schafer wrote: You won't do it with band pass cavities unless you crank the insertion loss way up. What would work for the two simplex radios with the 660 Khz spacing is a pass/notch duplexer. It needs to work just like a regular repeater duplexer with the same kind of isolation from one radio to the other. You need in the neighborhood of 70 to 90 db depending on how good the radios are. Very hard to get with pass band cavities. Just look at the curve of a pass band cavity at different insertion loss settings and move off of center frequency 660 Khz and you will see how far down the attenuation is. Most cavity manufacturers have those curves on their web site. Look at different size cavities, 4, 6, 10 and you will see that the larger cavities are better (have steeper skirts) than the smaller ones. Most will show curves for two cascaded cavities too. You will quickly see what is needed for pass cavities to get the isolation needed. When you get the repeater frequencies you will probably have to start over again. Two antennas would be a big help if you can do that. 73 Gary K4FMX -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:Repeater- [EMAIL PROTECTED] On Behalf Of John B Sent: Thursday, October 04, 2007 12:51 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] duplexer isolation and reciever noise budget I'm attempting to design a system that will have a VHF repeater (freqs not yet determined) sharing an antenna with 2 packet radios (APRS on 144.39 and Winlink on 145.05, either of which may be active as a digipeater at any time). I'm currently considering a bandpass-only quadplexor to isolate the radios from each other.. each radio running through a bandpass filter tuned to its frequency only (that includes the transmitter and receiver for the repeater), on the theory that it is a lot easier to pass one frequency than it is to reject 3 others. Assuming that none of the transmitters run more than 50w, how many DB down do I need to be outside of the passband to minimize desense for any of the 3 receivers ?? Any other suggestions on how I might handle this hookup would be greatly appreciated. I'm nearing completion my trailer-mounted 40ft crank up tower, and I'm having some problems budgeting space for a filtering system with 12 bandpass cavities without cutting into general cargo space. Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Re: Duplexer and noise question
If it works into a dummy load without desense you either have a feedline/antenna problem or external noise and most likely not the duplexer - be sure and use an isolated TEE and sig gen with a dummy load to test. Steve NU5D jminn699 wrote: -I am having the same problem also with a wacom duplexer. On a dummy load the tunning checks great with no desense, but with the antenna attached the repeater will hang on transmitting noise as long as the ttansmitter is on. I can`t take the system off the air, and I don`t have another duplexer. My short term solution has been to set the repeater hang time to zero. Another would be to make the tx pl different from the rx; but I am hoping to avoid reprogramming all the radios on the system. My system is located in a lousy enviorment, a elevator equipment room-there is a layer of carbon dust on everything. I suspect that this dust may have found its way inside the cans, but I can`t take it off the air to open up the cans. I hope someone has a solution to this problem. Joe -- In Repeater-Builder@yahoogroups.com, Dan Cation [EMAIL PROTECTED] wrote: Hi everyone - new to the group looking for help on a strange problem. I've been involved with two repeaters in Southeast Kansas (Humboldt - 147.18 and 442.900) for over 30 years and work in Electronics, although not in radio. A couple months ago we lost both repeaters when we had a flood in this area - I took the Wacom duplexer apart and cleaned any obvious corrosion or such and assumed it would be fine - it tuned up without any trouble and there was almost no corrosion. I replaced as many of the T connectors as I could and carefully cleaned any that remained and made new cables of the correct length. I have built a new repeater but am now having a problem with intermittent buzzing sometimes when the transmitter is up - it will hold the receiver open and cover any signals that aren't pretty strong. Comes on whenever the transmitter comes up but not always - sometimes it is fine. I have tried 3 different transmitters - a Midland 3400, a Midland 340A and even a couple Icom rigs - makes no difference. Same for receivers - makes no difference. Never shows up unless the duplexer is hooked to an antenna - works fine on a dummy load. Tried two different antennas as well. The noise sounds like bad line noise, but I can't hear it except on the repeater. The repeater is at my house right now, but I intend to haul it back to the site to see if it shows up there as well when I can get time to do it. Anyone else ever ran into this kind of thing? Yahoo! Groups Links -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Overlapping Coverage
The idea with simulcast is to keep the non capture area as small as possible. Typically the capture area is that where the dominant transmitter has a 10 dB or greater advantage. In capture areas subscribers hear only one signal A good test is to broadcast different audible tones from each site and see which tone is heard. Running as high power as possible keeps the capture areas as large as possible and minimizes non-capture areas. For simulcast to work the signal in the non-capture area needs to arrive in the non-capture area at the same time from each contributor. Most systems are designed in a straight line so that the outer sites don't overlap. The GPS signal is used to discipline a master oscillator at each site. Every transmitter uses the same MO. Depending on the number of channels, you may want to use receiver voting along with bulk delay in a 1.544 mb/s T1 stream. Contact Ed O'Connor at Simulcast Solutions or visit their site for some good information. http://www.simulcastsolutions.com/ 73 Steve NU5D Bill Powell wrote: I'm considering a trunked (type TBD) system on 470 that will have significant on-channel overlap. The overlap comes about due to the need for multiple sites to fill the many holes that will exist with a single site regaurdless of location or (reasonable) tower height. Assuming that ALL the transmitters are GPS locked and properly set up for simulcast operation, what operational problems might I expect? Thanks, Bill Powell
Re: [Repeater-Builder] New Article: Mastr II self quieting
Once upon a time in the early 80s I worked on an Army Mars repeater that self quieted. Transmitter on 143.990 and received on 148.01. Seems like the transmitter used a X12 multiplier, and the receiver had a 12 mHz. IF. Took lots of screen wire and feed thru capacitors to make that puppy work. Steve NU5D ex AAV6NQ. Scott Zimmerman wrote: Fellows, I have finally published my article on why the UHF mastr II radio self quiets when converted to a repeater using low-side receiver injection. Please read over it and let me know of any problems or things that just don't make sense. http://www.repeater-builder.com/ge/mastrII/m2loproblem.html flame suit on Scott Scott Zimmerman Amateur Radio Call N3XCC 612 Barnett Rd Boswell, PA 15531 -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Spectral Power
I once heard of a term called Gain Bandwidth Product where the greater the bandwidth - lower the gain. FM commercial broadcast uses extremely wide bandwidth to support 15 Khz audio and good s/n. Business once used +/- 15 kHz transmitter deviation to support 300 to 3000 Hz, then +/- 5 kHz, and now +/- 2.5 kHz. I have had it explained that DSTAR has better s/n because of it's narrow bandwidth. My own observations in 460 mHz trunked radio, repeaters and systems, is there is not much noticeable difference in analog FM radios whether they are running 2.5 or 5 kHz transmitter deviation. Every one has told me that the s/n will be somewhat worse on 2.5 but I have not noticed it. This all considers the receiving station is intended to receive the bandwidth being transmitted. As far as the antenna goes - within reason bandwidth is not an issue - kinda like how bright is the light bulb in terms of power applied to the antenna - the bandwidth should not matter unless you get out of the design bandwidth of the antenna. Maybe some graduate engineering student has a thesis on this topic? Steve NU5D (tired old bench technician) Kris Kirby wrote: I've been milling a few things over in my head and one thing that has struck my mind and resonated is power versus modulation -- our 900MHz repeaters typically use a +/-2.5KHz average deviation, which is smaller than the VHF norm of +/-4.5KHz. At almost half the deviation, it would seem that one would obverse an apparent increase in signal power of a little less than three decibels. Here's where I'm getting confused: Does 50W RMS at 950MHz over +/-2.5KHz deviation mean the wideband (+/-4.5KHz) rating would be 25W? Does the antenna manufacturer even bother to take deviation into consideration when factoring power specifications? How does this factor in terms of power wasted as heat (in the unlikely case that I'll attempt to put too much power into an insufficently-sized radiator)? -- Kris Kirby, KE4AHR [EMAIL PROTECTED] * WAR IS PEACE * FREEDOM IS SLAVERY * * IGNORANCE IS STRENGTH * KETCHUP IS * * A VEGETABLE * -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Duplexers
A transmitter may have broadband noise with considerable noise content at the receive frequency. The notch in the transmit side removes transmitter noise that may impair your receiver's capability. In an earlier post there was mention of a solid state transmitter. Traditionally tube transmitters have higher Q output circuits as opposed to wideband circuits in solid state transmitters, so a solid state transmitter may need more filtering. There are also combination band pass / band reject duplexers and also band pass only. Each has a characteristic suited for a particular job. Beware, a duplexer may pass an intended frequency PLUS unintended frequencies outside the normal band pass. I found that 158.100 radio paging was being received by a dual band antenna, and passed right thru a 440 duplexer to cause overload in the receiver front end. In this particular instance the best solution was to go to a monoband antenna. Wishing you best success, Steve NU5D [EMAIL PROTECTED] wrote: Thanks for the great info as soon as we get the service monitor back we are going to try these things. I have already seperated the 2 sides and have seen much improvement so I think that this is really my problem. I do have a question about duplexers in general. I am sure that this is a dumb question but What is the purpose of notching out the receive frequency on the transmit side? Since I have 6 cans couldn't I move one of the cans from the transmit side to the receive side to give me 4 on the receive and 2 on the transmit? Thanks, Vern
Re: [Repeater-Builder] Duplexers
Time for an isolated TEE test with a dummy load. Why did you have the duplexers tuned ? Was there a problem prior? You should be able to split the duplexer without any trouble - just mark things so you can go back as it was. Best luck and 73, Steve NU5D [EMAIL PROTECTED] wrote: I am having some receive problems on my repeater and I am thinking that it might be desense. I am on 2M running a MASRII repeater with a Decibal Products band reject 6 can duplexer. While I can key the repeater from a pretty good distance the audio that makes it through the repeater drops off pretty quickly. I just had the duplexers tuned and they are tuned very well. So on to my question. If I were to take and seperate the recv cans from the xmit cans and run to 2 seperate antennas would that mess up the duplexer tuning? will 20' of vertical seperation plus the cans and the fact that I would be running through seperate cable, make a difference? Thanks, Vern KI4ONW
Re: [Repeater-Builder] Duplexers
Decibel did make a 6 cavity notch duplexer - 4 full sized cavities - that would work nicely on a 110 Watt M2 station @ 600 kHz. Isolated TEE test into a dummy load - how bad is the receiver desense ? If you don't have some test equipment - signal gen, dummy load, and a TEE fitting with the side pin cut away (makes 60 dB lossy coupling, there abouts) you probably will need to find someone who does locally that can help. 73, Steve NU5D Eric Lemmon wrote: Vern, Did this problem exist before you had the duplexer tuned? Was anything at all done to your repeater system just before the problem was noticed? A band reject (notch) duplexer may be incapable of performing even satisfactorily at 2m. Please advise the model number of your duplexer, so we can understand your situation. Are all of your cables double-shielded? It might be a good idea to perform a noise-floor test using an iso-tee and a service monitor. Some helpful information about investigating desense problems can be found here: www.repeater-builder.com/ge/datafile-bulletin/df-10002-02.pdf 73, Eric Lemmon WB6FLY
Re: [Repeater-Builder] Re: NFCC votes to recommend FCC treat all repeaters as repeaters
My DSTAR repeater has 3 inputs, and 3 outputs. In 70 cm it transmits on 442.000 and receives on 447.000. On 23 cm it transmits on 1292.1000 and receives on 1272.1000, and the high speed simplex data port operates on 1253.. Since like many programmable repeaters, I am not locked into a 5 mHz offset, I can use a 3 mHz split, or a 4.5 mHz split, or pretty much any 2 frequencies in the 70 cm band that I choose, like wise, in 23 cm digital voice, there is an input and output. Our Texas VHF FM coordinator recommended a 20 Mhz split, but I could just as easily used a 12 mHz split, or 15 mHz split, or what ever pair of frequencies I want. The HS DATA is simplex, but I believe I could have a different send and receive frequency but have never explored this facet - today I am using 1253.. I cannot imagine the 70 cm DSTAR repeater not having a transmit frequency programmed in, thus making it just a receiver in 70 cm, or just using the 1272.1000 receiver without also using the 1292.1000 transmitter. I don't even know what would happen if I left the transmit frequency blank when programming - I suspect there is a default number that would go into the synthesizer. When I send on 447.000 the repeater repeats on 442.000, regardless of any other setting. When I send on 1272.1000 the repeater repeats my transmission on 1292.1000 and when I connect to the internet this takes place on 1253. with a 50 ms turn around time. I cannot send on 447. without being repeated on 442.000 unless I choose a different transmit frequency. I don't know what would happen if I left the 442.000 transmit field blank. I don't know of anyone who has done this or any reason why anyone would have a repeater without haviing their transmitter functional. I can not send on 447. without my transmission being repeated on 442. regardless of whether I choose to cross band to 1292.1000 also, or choose to make a gateway call to London, I am still repeated on 442.. This is kinda like one of my first 2M repeaters that had a 10 Meter simplex drop that I could activate with touch tones, and I could also cross to my 6Meter repeater with touch tone commands if I wanted. It was still a 2M repeater. There is no reason you can't refer to these 2 repeaters and one simplex high speed data box as multiple inputs and outputs, but they are not independent of one another. They are 2 repeaters and a simplex data box (for lack of a better description). When I first installed the DSTAR system May the 5th, It consisted of 2 GE Phoenix radios, one transmit radio on 442.000 and one receive radion on 447.000 with some creative interfacing to repeat the DSTAR signal. About 2 weeks later, the Icom 440 repeater and controller arrived and we changed out the GEs for the Icom. Function was the same, except it now would ID in DSTAR properly. Next we connected to the internet to enjoy the gateway features, and next a few weeks ago we added a 23 cm digital voice repeater and a 23 cm high speed data repeater *loose term repeater because it uses one frequency, 1253.*. Maybe there is someone out there that does not use a DSTAR repeater as a repeater - I have never heard of this but there are many things I do not know. Best 73 and also KUDOs to the hard working unpaid volunteer frequency coordinators who do their split level best to make jello stick to the wall while they are trying to push wet spaghetti in a straight line uphill on a slippery slope at the same time while swatting at gnats buzzing at their sweaty faces. (No sarcasm meant - I really do appreciate the work these folks do) Steve NU5D . Bottom line guys gals, The D-Star units have two frequencies one for Transmit and one for Receive Incorrect. Most D-Star systems have multiple inputs outputs are networked via radio internet to other D-Star systems around the world. But a 2-meter D-Star repeater has ONE input frequency and ONE output frequency, and does NOT transmit point-to-point communications on that output frequency! What the rest of the SYSTEM has, or does, is irrelevant: if that 2-meter transmitter is not transmitting point-to-point communications, it is NOT in auxiliary operation. You are continuing to ignore the key requirement for auxiliary operation on any given frequency, that point-to-point communications are actually TRANSMITTED over that frequency.
Re: [Repeater-Builder] Simulcast questions
That would be Ed O'Conner at Simulcast Solutions http://www.simulcastsolutions.com/ Steve NU5D Brian Gieryk wrote: I am looking to set up a simulcast tx with voted rx system on VHF hi band (2 meters) using 3 MSF-5000 digital capable stations, with spectra tac rx'ers.
[Repeater-Builder] Making room for the new guy - repeater coordination - Hope this is not too off topic...
Illegal is Illegal period. Look at what there is to gain by promoting digital repeater technologies - more spectrum - less interference - better range and better quality communications - no pots to adjust on your repeater - 1s and 0s We have it within reach to re-farm present spectrum for a 2 for 1 or better yield in recovering spectrum by fostering digital technologies, be it P25 or DSTAR, or other means not to market at present. First - voluntary negotiated agreements - ie. Hey Joe, that repeater you have, you know, the one on the North side of town with the bad antenna - our group would like to share the channel and put up a new digital repeater and would like to partner with you - what do you think ? Second - Dear Coordinator - Old Joe has an unused repeater pair on the North side of town. We respectfully request you re-consider coordination because we the undersigned (hand full of folks) have monitored this frequency for the last XX days and find little or no activity - well beyond the alloted 90 days allowed for repair / replacement, and respectfully request Old Joe's coordination be waived to the extent we may construct and operate a digital repeater using part of the spectrum alloted to Joe while at the same time offering to share this spectrum with Joe. (Sharing a frequency is not interference). Third - Dear Coordinator - We have tried unsuccessfully to negotiate with Old Joe to share his un-used / underutilized repeater pair, and while we concede the station to be constructed and operational, we also note a lack of activity as documented herein and propose our group would better serve the purpose of amateur radio by being allowed to share this coordination. Maybe the wording is not so great, but the idea is to work within the existing rules to promote more spectrally efficient frequency use to the end that there is more spectrum for everyone. I do not believe DSTAR repeaters to be anything other than repeaters, and unless there is a proper waiver of the FCC rules, should not be placed in any part of the band where repeaters are not permitted. Again, thanks to the volunteer coordinators who do their best to make things fit for the betterment of our hobby and service, Steve NU5D moderator dstar_digital yahoo group. MCH wrote: I know, but in many areas there are a lot of unused frequencies. Still, I would never seriously tell someone to operate there. I would also not recommend operating repeaters in the parts of the band where repeaters are prohibited. Others don't see this prohibition as a deterrent, however. The reason? The repeater bands are full and there is a desire to put more repeaters on the air.
Re: [Repeater-Builder] Making room for the new guy - repeater coordination - Hope this is not too off topic...
Hi Glenn, If old Joe's repeater were usable and folks were making use of it by all means leave it alone. Poor old Joe's repeater is not working so well with a bad antenna, and it only has 2 folks that make contact for a couple of minutes a day. The folks wanting the digital repeater could help fix Joe's antenna and get it back in shape, but Joe don't want to mess with it. If they get is back in shape they have a 20 Khz FM repeater not much different than the others in town. If they partner with Joe and upgrade to digital, depending on whether they occupy the middle of the channel, or offset up or down 6.25 Khz, they can restore Joe's system to a ?better? system, and make room for one more repeater in the area. This is only because there are no more 2M or 70CM channels available in Joe's neighborhood, and the folks wanting to place the new digital system have no other place within the rules to go in the band they want. Never would I want wholesale run this through and make it happen, but thoughtful well planned migration might be a good thing. Also like you said, the new equipment would cost more than fixing the old system for Joe, but then folks would not have the benefits of the digital system - no white noise (garble instead), good comm grade audio, and a smaller occupied bandwidth. I certainly respect your comments, and your points are valid. I am just trying to put forth some ideas that will foster a planned gradual move for some folks to digital - by no means a wholesale jump like the cellular folks did. Also there are still folks with radios that don't have channel guard tone - some things don't change. Lets put your 2 cents and a few others together and have a cup of coffee, 73, Steve NU5D (BTW - I can assure you that not all land mobile operators, RCCs etc have buckets of money - forced migration in the SMR business was very costly for me, and this don't take into account loss of customers who didn't want to mess with re-programming radios) sb. Glenn Shaw wrote: Steve Wouldnt it be easy and more effective and cheaper if your: ...hand full of folks just go ahead and use Joes repeater that is already on the air instead of complicating the situation more than it needs to be? Of course Refarming ham radio wholesale will be ill advised and I dont think you will see it in our lifetimes.. The users of ham radio are not the US government or public saftey or RCC's with bottomless buckets of money to just go out and replace equipment. We are losing people in the ham radio community not gaining them. Most hams buy a radio and use it for years and dont have to For those that want to experiment and promote investigation of the new dig modulation such as DStar and P25 that is good and we should encourage this on new spectrum that can be found that is unused, without destroying the existing repeater sub bands. Just my .02 for thought. Glenn N1GBY
Re: [Repeater-Builder] Making room for the new guy - repeater coordination - Hope this is not too off topic...
[EMAIL PROTECTED] wrote: I think you'll find in most areas where the repeater frequencies are Full, that there are more repeaters to talk on than there are people to actually talk on them. And we need more repeaters? My point exactly, Larry - is ham radio best served by more repeaters than there are folks to use them blocking folks who want to try and revitalize things with a digital system? Look at http://www.dstarusers.org and see who is talking now. Maybe this digital stuff is just a fad, and when it dies out, channels used for digital should be returned to re-coordination, but to kill an innovation at the onset by not allowing a place to operate when there is unused / underused space available just isn't right. As far as constant chatter - I would not want that either, but there are some repeaters that are just plain dead. It also seems the assumption here is that Joe would not be agreeable to the new folks proposal, maybe he would be. Anyhow this is all intended in the spirit of amateur radio and I don't want to provoke any arguments or ill will, as before I am thinking about ways to make this work for everyone. Almost coffee time, 73, Steve NU5D
[Repeater-Builder] Re: Making room for the new guy - repeater coordination - Hope this is not too o
wb6ymh wrote: Technical question: Does a DSTAR radio automatically switch between analog and digital? i.e. can the DSTAR user hear the analog activity when his radio is in DStar mode so he can share the frequency? Sharing between digital and analog was tried back in the packet days... to say the least it didn't work. 73's Skip WB6YMH Hi Skip, Dang service call broke into coffee time, but I did get to visit the local hams for a bit. As far as I know the DSTAR user radios can be set to busy channel lock out, so they will not transmit when there is anything on the channel. They also have an S Meter that will show activity, and can be set to monitor for analog or digital. One down side would be the internet gateway. I can direct a call to the DSTAR repeater in Malibu, CA from here in Temple, Texas and have no idea whether the channel in Malibu had analog traffic or not. Local folks could be observant, but folks thru the gateway would not know. This may be how folks contrive the DSTAR repeater to be an AUX Station because it can be caused to transmit by another station via the internet in another area. This may be a secondary function, though, because primarily the repeater works as a repeater, and I would venture that 2/3 of the DSTAR systems in the US are not connected to the internet. 73, Steve NU5D
Re: [Repeater-Builder] Making room - testing DSTAR
I take care of a pretty large EDACS system. There is a simulator built into my COM120B just for EDACS and LTR - even decodes pocsag paging. This is never used in setting up the base station/repeaters. The procedure uses simple deviation and receiver tests. Same with subscriber units - most (but certainly not all) problems can be caught in conventional mode. On the repeater receiver a sniff point on the discriminator output allows basic receiver testing. This does not simulate DSTAR but gets to a go/no go point. Kind of like the first DPL - I had to buy an aftermarket board and wire it to my CE50 service monitor - would encode and if the light went out on receive - would decode as well. I doubt any manufacturer will make a test set for a low volume product because there are not enough folks wanting to pay for a DSTAR tester. Next problem - if the thing is broke - I am not gonna go probing around surface mount chips with my simpson and weller - better to box and ship. Anyhow that another 2 cents - might make payroll if this keeps up... 73, Steve NU5D Mike Morris WA6ILQ wrote: And one more point - and it's a major one You can get P25 test equipment. Show me one piece of test equipment - an IFR, an HP, a General Dynamics (the folks that made some of Motorolas R-series of service monitors) or any other test equipment manufacturer that makes a dstar tester. Not even the manufacturer has one. So haw do you verify that a dstar system is actually working right?
Re: [Repeater-Builder] Making room - testing DSTAR
No flames here, Mark, Maybe we should have stuck with straight keys - those bugs might obscure transmissions - maybe a 10 wpm speed limit. But no, folks added microphones and heising coils. Next thing the cans went to the sideline and there were loudspeakers, then Central Electronics with the multiphase exciter, and here comes sideband and warbulators2M and 6M AM gave way to fm - point being this should be progress - just as digital has surpassed almost every analog strong hold. Your telephone network has used PCM digital mux since the days of N Carrier went away - remember LD calls with cross talk in the back ground - gone. Digitized voice is in its infancy in ham radio, but I do believe with continued development it will continue to gain acceptance. I am not so big on critical traffic on ham radio - that is what public safety networks are for. We as hams provide comms for events like marathons, parades, etc, and during disasters, augment failed and downed public systems. Critical traffic is not intended to be hams mainstay. - kind of off topic for repeater builders, though. As for serviceability I have been a bench and field tech since 1972, when selenium rectifiers stunk, and tuned lines were king. We could actually repair radios then. Today, unless you have hot air soldering / desoldering stations and a microscope, I defy the average tech to get into board level repair - has nothing to do with digital, or smarts, or education and everything to do with automated manufacture and unbelievable reliability. It was unusual to see a tube radio in a butane truck go 6 months without some kind of failure. Now it's unusual for a modern radio not to outlast several butane trucks - things have changed. Our technology has changed too - the diddle stick is replaced with digital pots and firmware upgrades - flash new data and go. The really sad thing is my profession is also fast disappearing - 2 Way Radio Shops are turning into dinosaurs - we still change mics and volume controls and do minor repairs - but most major fixes go to a depot because who buys several thousand $$$ in custom repair and testing fixtures to change a 128 pin IC that cost $20 and fails in 3 out of every 500 radios in the first 2 years ??? So, no flames my friend - I too don't like all the change taking place but like a wise friend once said a bend in the road is not the end of the road, unless you fail to turn. 73, Steve NU5D n9wys wrote: Gentle people, Although I'm usually very open to newer technology, this digital (or better said, digitized) voice thing has me very concerned. As a public safety worker, I shudder to think that maybe some day I might need assistance and call for back-up, only to have my meaning misunderstood because a few As ham radio operators, one of our missions is to pass critical traffic... Now in regard to the testing/repairing these D-Star systems... I didn't become a ham until later in life, although I've always had an interest in radio. But since I have, I continue to strive to be more than just an appliance operator... I need to be able to understand how it works, and if within my means, troubleshoot and/or repair it. Based on the earlier statement that the only way to test/repair these stations is to box and ship it back to the manufacturer, I feel we as Amateurs are taking a huge step backward, both for ourselves and for our hobby. 73 de Mark - N9WYS
Re: [Repeater-Builder] Slick Identifier
Hutton no longer carries Comspec. I just ordered 3 ID8s yesterday. My account from 1985 was still good. Steve NU5D I wonder if I should have purchased one of the micro repeater controllers, though - get ID plus controllersb Mike Morris wrote: At 09:13 AM 09/20/07, you wrote: Milt I could not find an ID-8 to purchase. ComSpec did not list the item. I could have missed it. Your email settings: Individual Email|Traditional Change settings via the Web http://groups.yahoo.com/group/Repeater-Builder/join;_ylc=X3oDMTJlbzlwaG8yBF9TAzk3NDc2NTkwBGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDc3RuZ3MEc3RpbWUDMTE5MDMxMDMzNQ-- (Yahoo! ID required) Change settings via email: Switch delivery to Daily Digest mailto:[EMAIL PROTECTED]:%20Digest | Switch to Fully Featured mailto:[EMAIL PROTECTED]:%20Fully%20Featured Visit Your Group http://groups.yahoo.com/group/Repeater-Builder;_ylc=X3oDMTJjNTA0cWNiBF9TAzk3NDc2NTkwBGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDaHBmBHN0aW1lAzExOTAzMTAzMzU- | Yahoo! Groups Terms of Use http://docs.yahoo.com/info/terms/ | Unsubscribe mailto:[EMAIL PROTECTED]
Re: [Repeater-Builder] Digest Number 5793
Your local NOAA Weather station is a good test transmitter for frequency and peak deviation.. Steve NU5D JOHN MACKEY wrote: If your service monitor showed 13 to 15 KHz deviation from 3 different digipeaters in this area, something is definately wrong. The radios those digipeaters are talking to are designed for 5 KHz deviation receivers. Are you sure your service monitor is working correctly? Go listen to a local 150 MHz land mobile FM system and see what it measures that deviation to be. Be glad I trimmed this puppy ..
Re: [Repeater-Builder] Digest Number 5793
I am surprised. That has not been the case in the Temple/Waco Texas area. Steve Ken Arck wrote: At 04:29 PM 9/18/2007, you wrote: Your local NOAA Weather station is a good test transmitter for frequency and peak deviation.. Steve NU5D ---I disagree. I have seen MANY NOAA WX transmitters off-freq - some well outside tolerance. Usually however, (while their audio quality is overdriven, distorted and generally pure crapola), their deviation *is* within limits. Ken --
Re: [Repeater-Builder] Mastr III
try launching the program Mastr.exe /M3 and see if that does the trick. Steve NU5D Tina wrote: I recently purchased a Mastr III repeater and the person i bought it from said he would include the software. Well, after over a month I finally got the software and it's for a Mastr IIe (from what I have read they both use the same or similar software) it reads the machine OK but I cannot find where to to change the freq, I can only change the PL tone. Do I have the wrong software, or am I missing something? I really want to use this thing for my clubs main repeater, but I am rather exasperated at this point. Please help. KE7DZZ SNARS Tech Chair [EMAIL PROTECTED] Yahoo! Groups Links -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Any seen these?
Joe Tryzenski from Aerotron was the sales mgr - they were based in Raleigh NC - their claim to fame was a fiber optic control cable - the things would have some kind of malfunction in the control head - massive overheat - nice radio but poor reliability. User programmable. Had 2 units VHF - returned them both dead. Seems like State of Utah may have bought a bunch around 1990 or so. Steve NU5D Gary wrote: Anyone heard or seen the Teletec Corporation IQ 2000 Omni series radios/repeaters (circa 1987-?)? I'm looking for info on these so any help would be appreciated. I'm aware Teletec has changed hands and they claim to have no info on these but I'm still digging. Thanks, Gary Yahoo! Groups Links
Re: [Repeater-Builder] D-Star systems as auxiliary stations?
The first concept of D-STAR that I saw used 10 Ghz for the point to point connections between sites. Internet is cheaper and we are hams. Some time back I said if it walks like a duck, looks like a duck, quacks like a duck, it just may be a duck. I believe DSTAR is a repeater. I also believe there should be a framework to foster new more spectrum efficient technologies. P25, D-STAR and others not yet dreamed of. In other places there is a process to seek a waiver of the rules when there is no other means of operating. Could this work in our ham radio hobby? Better yet, find an under utilized repeater - meet with the owners and see if they would be willing to share - invite and educate them about the new proposed system. Who knows, they may be willing to partner with the new system. DON'T be gutless and spineless and go behind someones back and try and take their repeater pair by surprise. 73, Steve NU5D Jim wrote: George Henry wrote: The point-to-point communications within a D-Star system take place over a LAN, WAN, or the internet, not over-the-air. Therefore, I doubt very much that the claim that D-star systems are auxiliary stations will pass FCC scrutiny. Yes, I know that there already is a D-Star system in the San Francisco area operating in that sub-band, but most likely, no one has ever challenged its presence. If someone does, I'm betting it gets shut down. I would say if the input and output freqs are the same, it is NOT a repeater. However, if the input and output are different, it may still not be a repeater. Is it TRUE full duplex? Is it near real time vs. a store and forward technique? I'm sure there's other questions that should be asked as well.
Re: [Repeater-Builder] D-Star systems as auxiliary stations? - Delay
Wonder how much of the delay is inherent in the subscriber units, and how much is attributed to the repeater ? Measure response on simplex, then through a repeater, unless of course, these ducks aren't repeaters, then it won't matter. Coffee time, Steve NU5D /K5CTX B, Temple, Texas Jamey Wright wrote: From the demo I saw locally, it is near real time. There is some delay but it is only noticeable if you are close enough to hear the transmitting and
Re: [Repeater-Builder] D-Star systems as auxiliary stations?
Except for the Simplex High Speed Data, (128K on 1250 Mhz) the i/o uses an offset on DSTAR. 1292 uses either 12/20 Mhz. 440 in Temple uses 5 Mhz, and 2M uses whatever they can get. Look at the list of repeaters on www.dstarusers.org for more details. There is a delay caused by coding the voice in the transmitting subscriber unit, and then decoding the voice in the receiving subscriber unit, plus whatever delay is encounter in the repeater. There is also delay in some squelch tail eliminator circuits - buffer the voice - and chop off the burst of noise and unkey before it gets to the transmitter. Works in function like reverse burst, but does not rely on tone codes. So far the only real argument deals with delay, and there are plenty of analog repeaters with as much or more delay than DSTAR. Would running your plain old FM repeater's audio thru a dsp board or an audio delay for squelch tail elimination make it no longer a repeater ? Steve NU5D /K5CTX B Jim wrote: MCH wrote: If the I/O is the same, it cannot simultaneously retransmit and cannot be deemed a repeater under the current Part 97 definition. Part 97 does not consider simplex repeaters to be repeaters. Joe M. My point exactly. begin:vcard fn:Steve Bosshard n:Bosshard;Steve adr:;;503 B. South 25th. Street;Temple;Texas;76504;USA email;internet:[EMAIL PROTECTED] tel;work:254-773-1102 tel;fax:254-773-1174 tel;home:254-770-0111 tel;cell:254-624-4230 url:http://www.bosshardradio.com version:2.1 end:vcard
[Repeater-Builder] More efficient use of spectrum.
The full D-Star stack of VHF, UHF, and 1.2 GHz all at the same physical SITE is a waste of spectrum, and should be avoided also. Nate Duehr There are around 14 DSTAR users in Temple, Texas, and our neighbors in Waco and Austin are moving forward with their own systems as well. The 'full stack' may indeed be a waste of spectrum unless there is a need for more capacity. I am finding the 1253. digital HS data repeater is unique to the system - no voice just 128kb/sec data. Thus far we have not set up a network between stations, just tested the internet connection and it does work at around 80kb/sec. (3 of the 14 have 1.2 capability and the number will grow). Also the coverage at 1296 is not bad (different than 2M or 440, but not bad). There are many times when a user wants a local chat on 2m/440 (not necessarily both) and there are times someone wants to use the gateway to make an out of area contact. Having 1292.1000 digital voice plus either 2M (very crowded most places) or 440 (not as crowded here in the sticks) while not a full stack, does have a place, and 1.2 G is pretty much under utilized most places. Propagation on 1.2 Ghz makes frequency re-use less of a challenge. Add to this an occasional traveler through the area, and with the Belton Hamfest bringing several thousand hams to the Temple/Belton area a couple of times a year, I can see how a single repeater might be less than ideal. Having DSTAR Chat run concurrent 1.2kb/sec low speed keyboard chat with digital voice at the same time on any of the digital voice repeaters is also a nice added feature that better utilizes spectrum. (You cannot have separate voice and data transmissions - low speed data rides with voice whether you use it or not) Add to this the 6.25 Khz bandwidth for still better spectrum utilization. I cannot see using a 20 Khz channel in 2M plus a 20 Khz channel in 440 to duplicate efforts unless there is a real demand, but I can see 23 Cents added to either a 440 or 2M system to offer some unique features. Seems like the 23 cent HS data repeater is a simplex operation that is around 200 Khz wide and could not pratically be used in the lower bands. I believe coordinators should offer incentives to more spectrally efficient technologies such as P25 and DSTAR. This will ultimately open more spectrum over time, and while I agree both P25 and DSTAR are repeaters, rule changes to foster more spectrally efficient technologies may be indeed appropriate, especially when dead repeaters block the use of channels that would otherwise be used. It does seem (while the new hasn't worn off yet) there is a surge of activity on DSTAR repeaters while many other repeaters lay virtually dead. Time and the market will tell. Visit http://www.yahoogroups.com/group/dstar_digital for D-STAR ONLY discussions. 73, Steve NU5D /K5CTX A or B
Re: [Repeater-Builder] Re: Frequency coordinator authority (was Re: subaudibe tones..)
Nate Duehr wrote: But... I'll point out that even the Icom VHF/UHF D-Star systems are just mobiles in a box... which anyone who has worked on a properly engineered repeater knows... SUCKS -- on many levels. They are $1500 mobiles in a box. Not $6000 M3 or the like. Maybe not a good value. Certainly not top of the line. Lots of hams see a repeater as a used base or mobile that can be converted to repeater operation. Lots of M2 mobiles out there, and Micor hand me down stations. No argument that the Icom DSTAR could easily be 5 times as expensive. No argument that they are a couple of not so hot mobile radios in a box. No argument that they are cheaper than a new Master 3 or Motorola product. I don't think Icom would sell many stations at $6000 to $10,000 a pop. But it's selling, so I guess people don't care. The quality level of these systems will certainly come back to bite someone in the ass, sooner or later. I keep asking how Icom's planning on allowing for field repairs, and getting nothing from owners. I guess you send the whole thing back to them... No user serviceable parts inside. I don't know about you, but when a system module fails on a M3, (over $2000 board) or a systhesizer goes out of lock - I box and ship the module. Let a depot do the repairs. I am too damned old to see much of the SOT stuff and could easily do more damage than good with a soldering iron. Other things as negatives include : - No service monitor adding the D-Star protocol or Icom's particular flavor of it natively to their test suite. - Bad behavior when co-channeled with other D-Star or analog systems. - Proprietary/closed CODEC (AMBE) I can't listen to ProVoice either. I can look at the demodulated transmit waveform, and I can inject a signal into the receiver and look at discriminator output, but I can't take my COM120B and shoot a ProVoice signal into a radio and listen to it thru the speaker. And I'm certainly not going to gamble club money on all of that. Better than a club - I took my own money and bought the stuff. No government grants, no committee taking years to decide how to do things. Benevolent Dictator. (Trust me, I love digital technology, and want to see hams using it -- I just find the current products from Icom somewhat hard to take seriously. Some would say I'm a P25 fan, but not really that either... the callsign-based Internet routing of D-Star gives it an edge for the Ham market that P25 can't touch. But at least the P25 repeater offerings were designed to be repeaters, and the test gear manufacturers all have products that can actually test their performance in real-world conditions. For commercial operators, MotoTRBO is fascinating too, but again -- lacks ham specific features and test gear...) Is MotoTRBO the right tool when you only need one voice path? or does it have to run with 2 time slots ? H(kind of like AlkaSeltzer - plop plop fizzz fizzz,do you really need 2 tablets or is it a marketing ploy)? -- Nate Duehr, WY0X [EMAIL PROTECTED] You have good and valid points Nate. I am just looking at things a little differently. Not a right or wrong thing. Actually this BP medicine makes me get up in the middle of the night and I had the computer running, and stopped to shut it off when I saw your posts. Back to bed, Best 73, Steve, NU5D
Re: [Repeater-Builder] Re: ltr repeater system
I think I have had enough ESAS for one natural lifetime. Actually, except for the remote computers locking up, and loosing track of circuit index, the stuff actually worked pretty well. Had it roaming, multisite dispatch, etc. Used Multitech VOIP equipment to tie sites together and remote print servers for RS232 links. When it worked it worked well. Got tired of having to go to sites for hard reset. Watch dog timers would not hunt ! Steve Tom Parker wrote: Try to buy a Trident Raider book... $35 hardly buys the postage... Also, home channel needs to be FB8 if at all possible. Steve, want to buy some more Uniden ESAS switches? We have four sites of six channels each! thp skipp025 wrote: Hi Mike, Nothing wrong with the way most Zetron Products work. My beef with Zetron is how they dropped all support after 5 years on some high end Zetron Products I have here. Then they tried to charge me $35 f No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.484 / Virus Database: 269.12.10/977 - Release Date: 8/28/2007 4:29 PM
Re: [Repeater-Builder] Re: subaudibe tones..
If you S1 is like mine Chuck, do you remember the low battery alert - the user could not hear it, but everyone else could ? steve - former S1 owner. Chuck Kelsey wrote: Yep. That's what I did, added a ComSpec encoder to my 4AT. My Tempo S1 has the added encode with DIP switch. Both radios work fine today. Chuck WB2EDV
[Repeater-Builder] LTR Rocks !
Kinda off track for a Ham repeater group, but been there done that. Mine was due to loss of 800 SMR channels when they were easy to come by, then later impossible to get due to freezes. Exclusivity. You need at least one repeater that has exclusive use in a service area because LTR uses centralized control and the HOME repeater needs to be exclusive. Having the second repeater also exclusive is a big plus. Next narrowband vs wideband. Depending on location you may be narrow band - that seems to work OK. You need two repeaters and controllers. Some repeaters like the Johnson VX have logic built in. Others use IDA, RLC, Trindent, Zetron Model 42, etc. You should be able to handle 6 to 10 groups of 10 to 15 radios pretty comfortably - probably more. The curve for users vs channels is exponential as adding a channel makes much more capacity than one channel by itself. Best success, Steve NU5D wadeds2003 wrote: Hello group. Just looking at putting up a ltr system. I would like to go 2 channels for now just to see how it all works. My plan is to use it for my business plus sublease some space to other companies. Has anyone here ever tried a 2 channel ltr system before? How does it work compaired to a larger system? A tech over at trident told me not to waste my time with a 2 channel system as he said it would not work but I have talked to other people who have done 2 channel systems and
Re: [Repeater-Builder] Re: ltr repeater system
An LTR mobile will try and access the repeater - short data transmissions, even if the base repeater's transmitter is inhibited. Some of the older stuff had to hear the data word from the repeater first in order to transmit, but newer radios, though they cannot handshake with a dead repeater, will try. Also if the home repeater is locked out, the subscriber units have no way to go to repeater 2 unless repeater 1 (locked out due to busy channel) tells the mobile to go to rept 2. So, you need at least one exclusive channel for the system to have any reasonable chance of working (or else use a very poor guard receiver.) Steve NU5D Jim wrote: I have to agree with what Skip said. The big issue with LTR (and other trunking formats) is that you have to either 1)have an exclusive license for each channel for the area you want to cover (may be hard to find, and licensing is expensive once you do), or 2) put monitor rx's on each OUTPUT freq. at the site with a cross busy to keep that channel from being assigned when someone else is using it down the road. The CSI unit Skip mentioned does have that provision, among most others.
Re: [Repeater-Builder] LTR Rocks !
LTR indeed does not use a dedicated control channel like EDACS or PP - control is distributed. Subscriber units are programmed to seek a HOME repeater and if it is not available (busy channel inhibit) the radios homed to that repeater are dead. When the home repeater is servicing a call it at the same time tells subscriber units to find a new home on RPT #X and will continue to send that data word even after the user on the home repeater is finished, so long as the transmission continues on the new home to service late entry. LTR is considered by the FCC as centralized trunking. De-Centralized trunking lets mobile units decide when to transmit. LTR does not have a provision for the mobile radios not to transmit on a busy channel. In centralized trunking, the site orchestrates mobile transmissions. But I may be wrong, Steve NU5D Jim wrote: Steve S. Bosshard (NU5D) wrote: Kinda off track for a Ham repeater group, but been there done that. Mine was due to loss of 800 SMR channels when they were easy to come by, then later impossible to get due to freezes. Exclusivity. You need at least one repeater that has exclusive use in a service area because LTR uses centralized control and the HOME repeater needs to be exclusive. Not quite true. LTR does not use a control channel, and does not transmit continuously, however, if you do not have exclusivity on a channel-ANY channel-you need a monitor rx on the output cross-connected so that it prevents that channel from keying if it hears other traffic. Having the second repeater also exclusive is a big plus. Next narrowband vs wideband. Depending on location you may be narrow band - that seems to work OK. 512 MHz and down to 136 or whatever will all be narrowband by 2013 anyway, except I haven't seen provisions for it for part 95 (GMRS) yet, so it will likely be exempt.
Re: [Repeater-Builder] Re: ltr repeater system
I have 14 channels at 3 sites running Johnson VX on 800 - they tell me the VX logic was developed by Trident. In 460 Waco is a 4 channel Uniden Esas, Temple is a 5 channel Uniden ESAS, and Killeen is 5 channel ESAS, Killeen and Temple were originally a mix of Ida RLC's and Zetron 42's - the 42' and RLC's never gave any trouble. Several other sites have a mix of 460 VX with on board logic and RLC's and Model 42's. Have somewhere around 50 channels of LTR running. Steve Mike Mullarkey wrote: Skip, If I can add my two cents in, use the Zetron controllers and your project will be much easer and work. Not knocking the other controllers, im sure there are plenty of good controllers but I just have the most experience with the Zetron controllers. Mike
Re: [Repeater-Builder] Duplexers
Generally the duplexer only makes a slight contribution to the reflected power. How doe the reflected power between the transmitter and antenna, without the duplexer in line look? Steve NU5D dallasreact112 wrote: Anyone one know what to expect SWR wise with a duplexer? I have a DB products 2 meter duplexer on an amateur repeater. Measuring with a Bird wattmeter between the duplexer and antenna I read 50W forward and a couple watts reverse. That is ok. But when I check between the transmitter and the TX port on the duplexer I get a about 60 W forward and 25W reverse power. Is there a rule fo thumb for a known good SWR value thru a duplexer? Should a good duplexer introduce any significant SWR? Thanks Bernie Parker K5BP Yahoo! Groups Links
Re: [Repeater-Builder] Cushman CE-5
Saw this on eham.net 2007-07-14 *KD0YX http://www.eham.net/user/profile/KD0YX* Test Equipment *FS: About 20 Cushman Plug Mods $50 Ea http://www.eham.net/classifieds/detail/235720* I have a large selection of about 20 Cushman Plug in Modules. I know they will work fine for the CE6 Series service monitors but may fit others like the CE3. Please check your manual. I need to get $50 each plus shipping. I can take PayPal or a Postal Money Order. I will leave this listing up on the swap board for remainder of July. In Early August whatever is left will go on Ebay. I have the following: 301, (2) 304B, 304, (3) 303, (4) 305, (2) 306E, 305B, 305, (2)308, 301,301A, 303 and 308. hwingate wrote: The power transformer in the 301 scope has died. Does anyone know where I might find the transformer or a junker for parts ? This scope is used in both the CE-3 and CE-5. Thanks Henry, K4HAL Yahoo! Groups Links
[Repeater-Builder] TNC Carrier Detect, DCD
Best I recall there was a choice between hardwiring COR to the TNC or using internal Data Carrier Detect for the TNC to recognize activity on the radio channel. This was an input signal from the radio to the TNC. Way back whenSteve NU5D Nate Duehr wrote: Nate Bargmann wrote: * Ron Wright [EMAIL PROTECTED] [2007 Aug 03 08:48 -0500]: Nate, I looked in my KPC-3+ manual and they do call out a DCD line on both the RS232 DB25 connector, pin 8, and also on the 9 pin radio connector. However, I cannot find any reference to it in the manual. Probably there, but cannot find. Wonder why they could put in a simple chart saying pin 1, does this, lo or high to turn on/off. In the RS232 spec the pin 8, known as CD, is Receive Line Signal Detector. It does take the unit on/off line. So I am assuming if the CD (DCD here) is in off state then the TNC will not do anything including receive or transmit??? Perhaps this was dropped in the newer KPC-3 command set, but my old KPC-2 version 5.0 has this to say about the CD command: CD INTERNAL | EXTERNAL | SOFTWAREv3.0 ... When set to EXTERNAL, the carrier detect is supplied by an external device, connected to the XCD pin on the radio port. That's what I remember also... my KPC-9612 is so old, I have no idea what firmware is in it. Last time I checked the internal battery was dead, and it's been sitting on a shelf for years... I have lots better ways to move bits around these days than ham radio... sadly. Nate
Re: [Repeater-Builder] Your old work bench - shop pictures are on ebay!
Ever run a 6V Carter on 12 V - gets kinda broad on the output. Steve NU5D Beats a Mallory 1701 hands down. Paul Finch wrote: How about a Dynamotor? Worked on, talked on 100’s back when I first started in two way business. Course they had a vibrator in them also for the receiver. Still have a bad back from them! Paul 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/
Re: [Repeater-Builder] non-silver RG-214 was Lloyd is Well was Cable Lengths
Do I need to call Lloyd again?? Steve NU5D Bob Dengler wrote: At 7/30/2007 02:21 PM, you wrote: Bob That doesn't square with the large body of repeater owners who have used Wacom cavities. Their UHF products used RG-142. However, their VHF
Re: [Repeater-Builder] Rohn 25g Tower
I tried something a little different in fastening a house bracket. I took 2, 4 Ft lengths of 3/8 all thread rod. I welded one end of each all thread to 1/2 of a 5 X 7 X 1/4 steel purlin clip. A purlin clip is a flat soft steel plate used to join 2 red iron steel purlins. After welding, the contraption looked like an oversized fly swatter. I then drilled 2 holes in the fascia and ran the all thread from the attic outside the house thru the fascia board. Next I ran 2, 1/4 X 2 1/2 bolts thru each clip (plate against the truss) with the bolts going thru the truss and thru the clip. I used flat washers on the wood side of the truss. This allowed the all thread rods, securely fastened to the truss to go outside the fascia for attachment of the house bracket. I believe this gives a little more strength to the attachment. The tower was pretty much self supporting to begin with, but this gave an extra measure of safety. At 90 mph wind, each foot in length of the tower has 113 pounds of force exerted by the wind. This can be a formidable amount of force. Best success and 73, Steve NU5D Jack Taylor wrote: Depending upon the wind loading on the tower, I would be cautious about fastening *anything* to the fascia board of a modern day house! If your tower is self supporting, design the base to handle the load. Don't rely on the house else over time you may end up with cracks in the interior walls. If the tower is to by guyed, don't use the house for an anchor :-) But on the otherhand if it is a short tower with little wind load, have at it! Jack - N7OO
Re: [Repeater-Builder] Coax length between added cavity and duplexer
W5AC at Texas AM has a 2M repeater on 146.820 co-located with an 800 Mhz PST. The 146.820 transmitter mixes with one of the 800 mhz transmitters and has a direct hit on 146.220. They use split channel guard tones because if in and out tone were the same, the transmitter mix would open the receiver. They could have left tone off the transmitter, but then the co-channel 82 repeaters would be an issue to folks listening. The ham repeater is a MastrII. Seems like they moved the 2M repeater from Kyle Stadium to Rudder Hall and the problem lessened but did not entirely go away. PS - I called Lloyd Alcorn this morning but got his answering machine - will call back later in the day. Steve NU5D. Jim wrote: Ron Wright wrote: Nate, A local, in Tampa, FL, high profile repeater has a similar problem. They are on 2 meters along side a 800 MHz repeater which gives them interference. They have to live with it. However, it is weak and they PL'd their repeater. Since weak the users can over ride and the PL only allows the users to bring up the machine. Wow-an 800 repeater is giving a 2M rx problems? Must be a really crappy rx! Or the antennas are REALLY close! -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Lloyd is Well was Cable Lengths
The question was a band pass filter between a receiver and a duplexer. First thing Lloyd said was lengths between cavities and the output TEE, comprising a duplexer are extremely critical. The original post cited a working system with interference, hence a band pass filter between the receiver and the duplexer, followed by questions concerning cable lengths between the receiver and in line filter, and the inline filter and the duplexer receive port. The supposition being receiver overload in the ham repeater coming from the 155? Mhz public safety system. Often a BPBR cavity may not reject signals 5 to 10 mhz from the pass frequency but do a splendid job of rejecting signals 600 khz from the pass frequency. Your pdf is excellent and very well done. Thanks for the great presentation Jeff. Best regards, Steve NU5D Jeff DePolo wrote: According to Lloyd, the cable length between a duplexer and an inline cavity filter and the receiver makes little or no difference. Steve, Was the question posed (or probably misunderstood as being) whether the cable length between the receiver and the filter being critical, or the cables between filter sections being critical? If the latter, then I would have to humbly disagree with the answer, as theory and personal experience, as well as the results of the test earlier today, has been to the contrary. --- Jeff
Re: [Repeater-Builder] Re: Coax length between added cavity and duplexer
Lots of times those BpBr cans will pass stuff not too far from the desired pass freq - A 2 loop BP cavity could very well help with receiver overload from a 155 Mhz signal - a simple test would be to hook a receiver to the REC port of the duplexer and see how strong the 155 Mhz signal is. As far as the placement of the BP cavity in line with the receiver, first, kill the transmitter and see what the receiver sensitivity through the duplexer might be. Next, add the BP cavity and see how much it impairs the receiver - then you decide - Me thinks the cable lengths won't make much difference, but as my friend Jack Daniel at RF Solutions sez, but I might be wrong. Best 73 and let us know how the extra can works out. Steve NU5D skipp025 wrote: I don't have time to debate or argue the point...
Re: [Repeater-Builder] Mastr III - Anybody using one?
Whilst I have my GE books out, was anyone needing any info on the M3 or M2e - lemme know - Steve NU5D Jim wrote: Jamey Wright wrote: Based on the year you specified, it was probably Mastr II or Mastr IIE although it could be Mastr III. I'm not sure when the Mastr III were introduced. I'll say either '92 or 93. They were still supplying MIIe's in '91 for EDACS systems.
Re: [Repeater-Builder] Coax length between added cavity and duplexer
You could always try and scrap the front end from a thrashed M2 mobile - kinda lossy but can be used as a preselector - Also even a 3 dB. attenuator might help against overload at the cost of 3dB. in RX sen. Out of curiosity, what kind of repeater are you using? Probably said in an earlier post - don't remember. 73, Steve www.bosshardradio.com Nate Bargmann wrote: * [EMAIL PROTECTED] [EMAIL PROTECTED] [2007 Jul 26 12:14 -0500]: Thanks for all of your input. I'm learning more as I go along. I did not get a chance to performance check the RX on site. It just happened that we were able to stop by the site a week ago and see what we were up against. -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Re: Mastr III - Anybody using one?
http://www.bosshardradio.com/m3 discg.doc You have to send this file to the repeater after you program the other info, and resend it every time you reprogram the repeater. Steve The Zetron file shows how to wire a Zetron Community Repeater Panel (or any other outboard controller - not recommended) to a M3 Station. Steve Jim wrote: Steve NU5D wrote Almost forgot - did have a problem with talkies talking down the channel guard tone - there is a software fix - hex code that once ctcss is detected - will remain detected until RUS goes away. sb Hey Steve, care to share that hex code? Having the same issue with a IIe station, HT's falsing the CG. TNX de Jim / KC2LEB -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] MASTR IIe dozing off
Be sure the control line is terminated. I have seen m3's get repeat disable from voice on the control line (even if remote control is not used). Vexing problem. Steve NU5D - BTW that tip came from Pete Lascelle at GE, or EGE, or Comnet, or MA/COM now days... Vincent Caruso wrote: Is it out of band? [EMAIL PROTECTED] mailto:[EMAIL PROTECTED] wrote: Have any of you experienced a MASTR IIe dozing off? No open fuses, no loose connections, it just forgets that it is supposed to key up when the receiver squelch opens. After resetting the control module, it works fine for a day or so and then the problem reappears. I'd settle for an over-the-air control module reset code (if one exists), but would prefer to get to the bottom of this. Any suggestions? _
Re: [Repeater-Builder] Mastr III - Anybody using one?
Bought new around 1991 - lost one driver module in the PA - use internal CWID/hang time, timeout timer, etc - Have outboard dtmf decoder tied to a 440 receiver to turn off the repeater, otherwise everything stock from GE - we do have a doug hall voter wired in using the local receiver plus 3 satellite receivers carried back to the hub on 438 mhz - been very solid repeater.We do not have any outboard controllers / noise makers wired in. The repeater is W5LM in Temple, Texas www.tarc.org Steve NU5D Almost forgot - did have a problem with talkies talking down the channel guard tone - there is a software fix - hex code that once ctcss is detected - will remain detected until RUS goes away. sb Tony L. wrote: Does anyone out there have a VHF Mastr III in service as a ham repeater? Feedback - good or bad? Sources for purchase of used/reconditioned? Yahoo! Groups Links
Re: [Repeater-Builder] looking for parts
Wacom built their duplexers from aluminum irrigation pipe, seems like they used several heavy metals in the electroplating process (outside company). I remember when the EPA shut down the electroplating company - dumping chemicals into the Brazos River - Wacom had to send their goods to Fort Worth for plating. Steve Anyone interested in how the Brazos got is's name? Steve Ron Wright wrote: Some have built coax, hardline type, duplexers for 6. When using 7/8 I've been told 1 MHz split is needed. Some have used 1-5/8 with better success. I have the plans from a site of 5 years ago if interested. Test data was given. Thars lots of metal in thar 6 m cans and they aint cheap...$2k is a common price new. Free from most commerical shops just to get rid of them. 73, ron, n9ee/r -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Re: crystal/channel element compensation..
I was thinking most every radio used a crystal (TCXO) as the reference from which everything else frequency wise is derived. One really stable oscillator vs many oscillators. Steve NU5D MCH wrote: Regardless of how many modern radios use temperature stabilization, that does nothing to diminish its effectiveness at keeping the frequency stable and eliminating the need for temperature compensation. Few rigs today use crystals for the operating frequency. Does that mean crystals are bad? Joe M. -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Dual repeater antennas..?
Sounds like you have the makings of a db 228 if you add the proper harness. Else maybe run the repeater on one antenna, and used the second antenna with proper cavity filtering as a diversity (term loosely used) receive antenna. Steve NU5D s3hampton wrote: I presently have a DB-224E as my 'main' repeater antenna. I have a second DB-224E available to me. The existing antenna is on a four-foot side-mount at the top of my now-40-foot tower. (The tower was a 140' self supporting unit, but suffered a failure; I am now using the remaining 40 foot 'stub' as the present position of the side-mounted DB-224E.) -- Ham Radio Spoken Here !!! EM11ma - South Mountain, Texas begin:vcard fn:Steve Bosshard n:Bosshard;Steve adr:;;503 B. South 25th. Street;Temple;Texas;76504;USA email;internet:[EMAIL PROTECTED] tel;work:254-773-1102 tel;fax:254-773-1174 tel;home:254-770-0111 tel;cell:254-624-4230 url:http://www.bosshardradio.com version:2.1 end:vcard
Re: [Repeater-Builder] Re: crystal/channel element compensation..
Just remembered another plus for rock bound equipment - used to be lower power consumption (before mosfet technology) because it took less power to run a xtal osc than to run a synthesizer plus a crystal reference oscillator. Don't know if power consumption is true today, though. Steve NU5D MCH wrote: Which is why I specifically said for the operating frequency - to eliminate the argument you just made. My point was that crystals are still fine for a repeater - as is temperature stabilization - even though modern radios may not use either. Sometimes, newer is not better. -- Ham Radio Spoken Here !!! EM11ma - South Mountain, Texas begin:vcard fn:Steve Bosshard n:Bosshard;Steve adr:;;503 B. South 25th. Street;Temple;Texas;76504;USA email;internet:[EMAIL PROTECTED] tel;work:254-773-1102 tel;fax:254-773-1174 tel;home:254-770-0111 tel;cell:254-624-4230 url:http://www.bosshardradio.com version:2.1 end:vcard
Re: [Repeater-Builder] D-Star
Thanks Ron - 73, Steve NU5D Ron Wright wrote: Steve, The link to the D-Star you gave is an e-mail address. Is the new group a yahoo group in the form of: http://groups.yahoo.com/group/dstar_digital This is the normal format for a yahoo group page. 73, ron, n9ee/r -- Ham Radio Spoken Here !!! NU5D EM11 http://www.qrz.com/callsign/NU5D Nickel Under 5 Dollars
Re: [Repeater-Builder] Acronyms-a little OT
The General Electric MCD (Mobile Communications Division) was big on TLAs (Three letter Acronyms). I always hoped there would be an LBI (Lynchburg Book of Instruction) outlining TLAs. We have GETC's, MOM PC,s IEA computers, CSD computers, The MOM looks at CIC's the TRIM, VMIMs, and AIC's as well as the EDG. GETC - General Electric Trunking Controller MOM PC - Monitor Module PC IEA is the Integrated Ericsson Alarm computer I don't remember the CSD - took the place of the System Manager CICs are Console Interface Cards TRIM is the Trunked Recorder Interface Module VMIM is a Conventional Interface Module and then the AIC Audio Interface Card. EDG is the Ericsson Data Gateway Ad Infinum Steve NU5D John J. Riddell wrote: * Eric, the Kids my grandchildren, use LOL as Laugh out loud in their E mails * * * * 73 John VE3AMZ * - Original Message - *From:* Eric Lemmon mailto:[EMAIL PROTECTED] *To:* Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com *Sent:* Saturday, July 07, 2007 10:07 AM *Subject:* RE: [Repeater-Builder] Acronyms-a little OT Doug, Here's my take: AFAIK = As Far As I Know FWIW = For What It's Worth IMHO = In My Humble Opinion BTW = By The Way FYI = For Your Information YMMV = Your Mileage May Vary LOL = Lots Of Luck (often misused as a meaningless closer) 73, Eric Lemmon WB6FLY
Re: [Repeater-Builder] Hello...
Howdy Lou, FB on wanting to put up a repeater. First step would be to see what demand/need for a repeater might be? Is there already a repeater serving the area and folks want to split off, or is this an unserved area, and folks who cannot operate simplex needing a repeater? For me that would be the starting point, next support, power utility, site rent, funding, etc. Wishing you much success, Steve NU5D Original Message Subject: [Repeater-Builder] Hello... From: lou_c1357 [EMAIL PROTECTED] Date: Tue, July 03, 2007 9:06 am To: Repeater-Builder@yahoogroups.com Hello all. Just joined the group, and looking forward to getting all the information that I can. I am looking at a long term project, and want to put up a repeater. I want to know where do I get started?? I am looking for the basics first, and then move along from there. 73 Lou KC2RVD
Re: [Repeater-Builder] ctcss and dcs at same time?
The DCS turn off code is 132 hz. So, 131.8 hz ctcss and dcs could be a problem. Otherwise we ran dcs with paging tones because tone coded squelch and paging tones do have issues. I would think the two would be OK, but where are you going to find a radio to encode tone and dcs at the same time? If you mean both on the same repeater at different times - no problem notwithstanding 131.8 hz. We have mixed ctcss and dcs on community business repeaters with no ill effects. Steve NU5D DaveH wrote: chances are one will interfere with the other. They would but be present and active at the same time. I have never seen it done successfully. David R. Henry LME Licensed Master Electrician Amateur Radio W2DRH Member ARRL Accredited Instructor
Re: [Repeater-Builder] ctcss and dcs at same time?
It would be a problem my friend because the 132.0 will cause the repeater to decode 131.8 during the turn off interval and ker chunk that tone briefly, with out any reverse burst. When the DPL radio releases the PTT it does not immediately quit sending, but instead sends a burst of 131 hz turn off code. If your panel is equipped for 131.8 it will ker chunk just a moment - no problem for hams, but on a business repeater the 131.8 guy will get annoyed. Wish I could remember if TOC is 131 or 132 - the data rate is 134, but thats another story - Seems like Ferritronics had an application not for this, if they were still in business. Have your self a super 4th, Steve NU5D mch wrote: A problem? Why? When the turn-off code is sent *after* you have unkeyed. Who cares what stops decoding after you've stopped transmitting, as any decoder should stop decoding then. Granted, the TOC could false a 131.8 Hz decoder, but not while the person is transmitting. Joe M. Steve S. Bosshard (NU5D) wrote: The DCS turn off code is 132 hz. So, 131.8 hz ctcss and dcs could be a problem.
Re: [Repeater-Builder] ctcss and dcs at same time?
I just left a 911 Med Dispatch Center - I am pretty sure a kerchunk every time another user keyed their radio and the TOC falsed their 131.8 PL would be a major issue. But, if you want to run 131.8 PL on the same channel with DPL and a turn off code kerchunking the radio every time they let off the key, go for it...again, not at the same time. Keep smiling, Steve NU5D mch wrote: Interesting reply given my statement Granted, the TOC could false a 131.8 Hz decoder You're describing a problem that may exist regardless of the dual CTCSS/CDCSS encode (the topic of this thread). Also note that it will still not interfere with each other. There will merely be a 'kerchunk' of the 131.8 Hz decoder from the 134 Hz (not 131 or 132 Hz) TOC of the CDCSS. Oh, and it would be just as annoying for hams as for business users. Joe M.
Re: [Repeater-Builder] Cable formula
That (isolator in place of tee) is how moto configured their Q package UHF Med Radio. The receive port gets the receive signal plus reflected energy that the preselector bounced back...never heard of that damaging an isolator, matter of fact, aside from burning up too small loads or lightning, I have never run into a damaged isolator, but I am sure there are instances - I have 14, 800 mhz smr boxes, and 80, 800 EDACS stations, plus 30 something UHF repeaters, I can only recall one piston capacitor failure on a telewave dual junction job. Steve NU5D. Gary Schafer wrote: Why would you ever want to do that? Unless you like destroying isolators. :) 73 Gary K4FMX -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:Repeater- [EMAIL PROTECTED] On Behalf Of Steve S. Bosshard (NU5D) Sent: Sunday, July 01, 2007 8:52 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Cable formula That would be the typical installation, unless you install the isolator at the output of the duplexer with the #1 (input) toward the TX cavities, #3 (load) toward the receive cavities, and #2 port (output) toward the antenna, used in place of the TEE fitting. Steve NU5D [EMAIL PROTECTED] wrote: Doesn't the isolator typically installed at the transmitter output spin off any anything reflected from the duplexer (or the feedline) into it's load? In a message dated 7/1/2007 5:33:33 P.M. Pacific Daylight Time, [EMAIL PROTECTED] writes: But at some off frequency that is not 50+j0 that impedance is going to get transformed into something yet again by the time the cable reaches the transmitter.
