Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK
Hi George, Thanks for the reply. I had downloaded the diagram for the Moxy earlier from that website, but discovered the connector is different for the Maxar 80. Not sure if the pinout #s are the same though. I could spend the money and get a manual, but that is another 20 dollars and more time, plus I don't think I need much information really, since the new target frequency is not much higher than the original frequency and may not need retuning. It's for a beacon transmitter, so RX tuning isn't necessary. Jeff KP3FT --- On Wed, 9/8/10, George Henry ka3...@att.net wrote: From: George Henry ka3...@att.net Subject: Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK To: Repeater-Builder@yahoogroups.com Date: Wednesday, September 8, 2010, 3:40 PM I know that they are available on the Batlabs site... try http://www.batlabs.com/nosynth.html and scroll down to the Moxy section. I believe that the pinouts for the Maxar, Maxar 80, and Moxy were all the same. George, KA3HSW / WQGJ From: KP3FT kp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Wed, September 8, 2010 1:58:15 PM Subject: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK Hi all, Does anyone have a scanned schematic and/or a pinout diagram for a Maxar 80 lowband? I moving one that is presently at 49.520 MHz, up to 50.065 MHz, but have no idea what the pins are for PTT, etc. There is no microphone or other cables that came with the radio. Thanks for any help. Jeff KP3FT
Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK
Hi George, If you don't mind going to the trouble, that would be great. Just verifying if the pin number/functions are the same as the Moxy would be good because I already have the Moxy pinout. 73 Jeff KP3FT --- On Wed, 9/8/10, George Henry ka3...@att.net wrote: From: George Henry ka3...@att.net Subject: Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK To: Repeater-Builder@yahoogroups.com Date: Wednesday, September 8, 2010, 7:45 PM I think I have a Maxar 80 manual at the office... I will check tomorrow morning. I think the only real difference in the connectors is that the Maxar 80 connector has 2 large pins at the top for power, while the Moxy has all pins the same size, and uses the first 2 in the 2nd row for power. All the metering, audio, and PTT pins are the same... I *THINK*... - Original Message - From: Jeff KP3FT kp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Wednesday, September 08, 2010 2:53 PM Subject: Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK Hi George, Thanks for the reply. I had downloaded the diagram for the Moxy earlier from that website, but discovered the connector is different for the Maxar 80. Not sure if the pinout #s are the same though. I could spend the money and get a manual, but that is another 20 dollars and more time, plus I don't think I need much information really, since the new target frequency is not much higher than the original frequency and may not need retuning. It's for a beacon transmitter, so RX tuning isn't necessary. Jeff KP3FT --- On Wed, 9/8/10, George Henry ka3...@att.net wrote: From: George Henry ka3...@att.net Subject: Re: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK To: Repeater-Builder@yahoogroups.com Date: Wednesday, September 8, 2010, 3:40 PM I know that they are available on the Batlabs site... try http://www.batlabs.com/nosynth.html and scroll down to the Moxy section. I believe that the pinouts for the Maxar, Maxar 80, and Moxy were all the same. George, KA3HSW / WQGJ From: KP3FT kp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Wed, September 8, 2010 1:58:15 PM Subject: [Repeater-Builder] schematic and/or pinout diagram, Maxar 80, D51TSA4000BK Hi all, Does anyone have a scanned schematic and/or a pinout diagram for a Maxar 80 lowband? I moving one that is presently at 49.520 MHz, up to 50.065 MHz, but have no idea what the pins are for PTT, etc. There is no microphone or other cables that came with the radio. Thanks for any help. Jeff KP3FT
RE: [Repeater-Builder] Wacom WP-639 Duplexer question
The PLL exciter is why you're having such good success running a 4-cavity duplexer. If you had a PM exciter, chances are you'd be experiencing desense. The PLL exciter produces about 22 dB less noise at 600 kHz offset, reducing the noise supression requirement of the duplexer by a like amount. See: http://www.repeater-builder.com/pdf/GE_Isolation_Curves.pdf The OP also mentioned he was using a preamp - that's not helping his situation either. Even with a good receiver he's probably on the edge of crunching it with only a 4-pack. Personally, I'd never run a preamp with nothing but a 4-cavity duplexer on 2m, but if it works for you, God bless... A Q202G gives more isolation than a WP639 from what I've seen/measured, in part because the cavities are larger diameter (I think they're 7 versus 5?). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of NORM KNAPP Sent: Wednesday, September 08, 2010 11:38 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Wacom WP-639 Duplexer question I got a set of 4 sinclair cans, like a Q202g on a GE mastr II running 100 watts with pll exciter and GE preamp with no desense. Antenna is roughly 300' away fed with LDF7-50A. Is this a miracle or typical? - Original Message - From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Wed Sep 08 20:10:44 2010 Subject: RE: [Repeater-Builder] Wacom WP-639 Duplexer question I'm not surprised- you're asking too much of a duplexer that has four 5 cans. According to my CommShop program, a duplexer with an 80 dB spec is more suitable with transmitter power in the 10-15 watt range, assuming a solid-state PA and a receiver sensitivity around 0.35 uV at 12 dB SINAD. On a 100 watt repeater, I'd expect something like a WP-642, which has six 8 cans. BTDT, got the T-shirt and mug... 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of RichardK Sent: Wednesday, September 08, 2010 3:11 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] Wacom WP-639 Duplexer question Good evening, our club has a Wacom WP-639 four can duplexer as part of our repeater system. Input Fq is 147.915 and Output Fq is 147.315. We have a 600kHz (+) offset. Very simply, our main problem is when we run the transmitter at full power 100 watts, there is a HUGE desense on the receive side of things. When we drop the transmitter power level to around 20-50 watts, the receive side opens WAY up to a large area where people can get into the repeater. As we begin to bring up the transmitter power, white noise begins to appear and the receive side starts to desense again. All the cables have been switched to double sheilded cables and all the same wavelength in length. We have the duplexer seperated sheilded from the transmitter preamp parts. We have not replaced the antenna feed coax with double sheilded coax yet. Antenna is a Hustler G7 atop a 55' mast. The duplexer was retuned just over 1 year ago. Any suggestions as to what we could look into next? Some of us believe the problem is with the tuning of the duplexer receive cans. Thank you very much.
RE: [Repeater-Builder] To DVP or not to DVP
If you have a nearby first adjacent (especially at 20 kHz), you might be better off with a standard receiver. Might be worth measuring it and comparing it against a standard receiver - I'd be curious to hear the results as I've never done that test myself. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tim Sawyer Sent: Tuesday, September 07, 2010 5:45 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] To DVP or not to DVP Hmmm... I didn't realize the DVP has a wider IF. I gather DVP requires up to 6 Khz of audio. So now I'm thinking that this receiver is not suitable for my busy hill (Santiago Peak). What do you think? -- Tim :wq On Sep 6, 2010, at 8:17 PM, Jeff DePolo wrote: The SP docs show it being a DVP station. DVP receivers have wider (and flatter) IF filtering than standard Micor Sensitron receivers. They need a flatter IF passband to decode DVP properly. I'm wondering if that's why the 20 dBQ reading comes out higher than normal.
RE: [Repeater-Builder] Micor UHF Sensivity
Not all voltmeters behave the same with complex AC waveforms (such as noise). Some of my Flukes are inaccurate at higher AC frequencies (like above a few hundred Hz) - and they're spec'ed that way. What kind of meter are you using, and where are you measuring (speaker terminals is where you should be measuring from)? Do you know what, exactly, the SP features/modifications are on your SP Micor? --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tim Sawyer Sent: Monday, September 06, 2010 6:07 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Micor UHF Sensivity The Micor book says less than 0.5 uV for 20db quieting or 0.35 for 12 db SINAD. So the two are in fact equivalent. I get better than 0.35 for 12 db SINAD but I don't measure 0.5 for 20 db quieting. I must be doing something wrong. -- Tim :wq On Sep 6, 2010, at 12:52 PM, John J. Riddell wrote: 2V AC down to .2 v. AC is 20 DB quieting John VE3AMZ - Original Message - From: Tim Sawyer mailto:tisaw...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Monday, September 06, 2010 3:48 PM Subject: Re: [Repeater-Builder] Micor UHF Sensivity I'm getting about 0.35 for 12 db SINAD. But that looks about 10 db quieting to me. What I typically do is open the squelch with no signal and set the volume to 2 Vac then crank up the signal to 0.2 vac. Isn't that 20 db, or am I missing something? -- Tim :wq On Sep 6, 2010, at 10:46 AM, Eric Lemmon wrote: spec is 0.5 uV without a preamp and 0.25 uV with a preamp, when using the 20 dB quieting method, and 0.35 and 0.175 respectively when using the 12 dB SINAD method
RE: [Repeater-Builder] Re: no power out of duplexer SOLVED with more questions
Or speed up the CWID one or two WPM, or change to a slightly higher tone frequency. Top 40 stations sometimes still do this trick (pitching up their CD players or automation system playback speed maybe 1%) - some PD's are convinced that it improves ratings for one reason or another... --- Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Joe Sent: Monday, September 06, 2010 6:38 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: no power out of duplexer SOLVED with more questions I agree. Put it back to the original output. I always like to turn my stuff back at least 10%. Turn the beep tone up in volume, tell them you increased the power. see what they say. 73, Joe, K1ike On 9/6/2010 5:04 PM, Paul Plack wrote: John, here's a more subtle lesson on repeaters, and it has nothing to do with hardware... If you dial the power back 1 dB, your PA may be much happier. If you simultaneously change the courtesy beep to be 10% faster, users will ask you what's changed on the repeater. Tell them you've increased the transmitter output 3 dB, and they'll claim to have noticed the improved coverage. Tell him guys...am I wrong? ;^) 73, Paul, AE4KR - Original Message - From: Tim Sawyer mailto:tisaw...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Monday, September 06, 2010 2:43 PM Subject: Re: [Repeater-Builder] Re: no power out of duplexer SOLVED with more questions
RE: [Repeater-Builder] Micor UHF Sensivity
I have tried with 3 volt meters and 2 SINAD meters: a Fluke 77, a Sinadder 3 (SINAD AC voltmeter) and a HP8924c. Pretty much same results with all. That is 20 db quieting around 0.7 uV, SINAD around 0.35. So what's the recommended meter? Should I trust the SINAD reading and chock the quieting reading up some unknown meter problems? Very odd. I'd probably want to load the speaker PA; I usually just leave the speaker connected or use a load box. Yes. The Micor came with a 3 page document detailing SP71 modifications. Would you like me to scan and email you a copy? I'd be curious to see if any of the mods would affect AF response, IF bandwidth, or anything else that could be throwing off your numbers. IIRC, older Micor manuals didn't even have a 12 dB SINAD sensitivity spec, only a 20 dBQ spec/test procedure. That's what I remember always using as a pass/fail reference. Of course, SINAD is a better test, but you should expect an in-band Micor to still meet the quieting spec. --- Jeff WN3A
RE: [Repeater-Builder] Re: Circular polarization for VHF repeaters?
It looks like the FCC rules give you extra power when opting for dual polarization. No, they don't give you extra power. For commercial stations, horizontal polarization is the standard. You can supplement it with vertical, either as cross-polarized linear, or as elliptial/circular, but that Vpol component's ERP can't exceed the Hpol ERP. For non-commercial stations in the reserved band (i.e. below 92 MHz) within the affected area of a channel 6 station, there are many cases where they are authorized for more Vpol than Hpol to protect channel 6 (which is presumed to always be horizontally polarized). The only extra power you get is additional transmitter power output (TPO) due to the reduced antenna gain (assuming the number of bays remains the same, and the same bay spacing) when you go from horizontal polarizaton to mixed polarity. That's a confusing point, I know. Every circularly-polarized FM station I've seen (and that's a lot of them) use an antenna design that handles the phasing and time-delay to create the circularly-polarized signal. That's pretty much correct, but there are many stations that have a vertical component added that isn't necessarily part of a circularly-polarized array. The vertical may be added as a separate radiator, but not phased with the Hpol radiators to yield circular, so you just have two non-coherent linear polarizations. Or a single linear radiator may be tilted to give slant polarization, which the FCC will accept as having both an Hpol and Vpol component, with the ratio being a function of the tilt angle. The license reference to H and V powers (regarding c-pol station) is intended to say how much ERP should some out when the signal is V and how much when it is H. It is possible to make the two components different, resulting in elliptical polarization rather than circular. They can be different, and yet not be elliptical. If they aren't phased together to yield a coherent rotation at all azimuthal angles, it's just random cross-polarization, not elliptical. 99% of the current topic was covered a year or so ago on this list - might want to revisit the archives. For those thinking about building Cpol bays, I'd suggest starting out with something simple like a ring-stub. Easy to make with a tubing bender (or Armstrong method), feed with a gamma, DC-ground at the mounting bracket at the rear of the bay, decent pattern circularity (but not great axial ratio symmetry), cheap and easy way to start. For those not familiar, a ring stub bay looks like this (I don't recommend OMB, it's just a decent picture of a very basic ring stub bay): http://www.omb.com/en/index.php?option=contenttask=viewid=78Itemid=38 Ring stubs are sometimes also called cycloids (albeit sometimes erroneously), often built with a balanced feed. You can try Googling cycloid, ring stub FM antenna, etc. for more pics and design ideas or email direct. --- Jeff WN3A
RE: [Repeater-Builder] DB212-3
I'm doing this from memory - I have the docs at home and can verify later. The DB lowband dipoles are 50 ohm feed Z due to the close spacing to the tower leg. 1 dipole - fed directly with 50 ohm coax (VB-8) 2 dipoles - fed with equal legs of 50 ohm coax (VB-8) to a tee, match 25 ohms from tee to 50 ohm feedline with quarter-wave transformer (35 ohm VB-83) 3 dipoles - fed with equal legs of 50 ohm coax (VB-8) to two mated tees (two mated tees give you four ports - three to bays, one for input) yielding 17 ohms. First transform 17 ohms to 72 ohms via a quarter-wave of 35 ohm VB-83. Then transform 72 ohms to 50 ohms with a 'twelfth-wave' transformer (1/12 wave of 50 ohm cable then 1/12 wave of 72/75 ohm cable) to result in 50 ohms to feedline. 4 dipoles - same as 2 dipole case, but add another tee, two more equal-length 50 ohm cables from the added tee to the 35 ohm matching sections on the bay pairs described above, and another final 35 ohm Q section from the new tee to the feedline These dipoles couple a lot of energy to the tower - you'll likely need even more vertical isolation than what free-space curves might otherwise predict. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Monday, August 30, 2010 2:35 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] DB212-3 Doug - Do you know how the phasing harness was constructed for the three-element version? I don't, and that's why I suggested to Norm that he go with four - the phasing harness is easy. Or, he could use two elements for transmit and one for receive. I don't know how much isolation he'll need, but he might just get away without a duplexer if there's enough tower. Chuck WB2EDV - Original Message - From: Doug Rehman d...@k4ac.com mailto:doug%40k4ac.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Monday, August 30, 2010 2:28 PM Subject: RE: [Repeater-Builder] DB212-3 In a previous life I managed the communications for a state police agency. We used 45 MHz for our main system and had forty some odd tower sites, almost all running DB212-3 antennas. Two of the sites were on 1000+ towers and used a single DB-212 element due to the large tower face and the great height. One was a repeater using a receive antenna at 1450' and a transmit antenna at 1350'. The other was a remote base station with the single loop at about 850'. As we were an investigative agency, almost all of the mobiles were using AM/FM disguise antennas. (Yeah, I know, but we were stuck with the band that the State Division of Communications had dictated...) Despite the radiating dummy load antennas, we had excellent mobile coverage in virtually all of the state. A consideration for DB212 antennas is that lining them up on one leg can make them pretty directional. For towers that were very close to the coast, I would put all three elements on a single leg, but skew them so that only one was pointed directly off of the leg. This seemed to give me a somewhat cardioid pattern, but with a little better pattern to the back than if all three elements were in line. Another consideration is that they were designed to be used on Rohn 45/55/65 sized tower. If you put them all on one leg, a larger tower face doesn't matter much except that the rearward pattern will likely have a larger null. Mounting them on all three legs of a larger face tower will result in reduced gain and a pretty messed up pattern. I don't know if I'd worry a whole lot about adding a fourth element- the three element antenna will deliver excellent results. Doug K4AC (Running for ARRL Southeastern Division Director- please check out my website at www.k4ac.com)
Re: [Repeater-Builder] Kenwood TKR-750 (VHF repeater)
IF you have a ver 2, you can do a mod detailed in the service manual by switching the position of some cap's to make it work on one port without a antenna relay. On Sat, Aug 28, 2010 at 3:11 PM, Ken Arck ah...@ah6le.net wrote: At 01:47 PM 8/28/2010, Juan Tellez wrote: For simplex use, you have to have an external antenna relay. -Yup. You need an external relay. Checkout RF Parts as they have fairly reasonably priced ones Ken -- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcontrollers.com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net We don't just make 'em. We use 'em! -- Jeff Ackerman Peninsula Communications 6 Rossi Circle, Suite C Salinas, Ca 93907 j...@peninsulacom.com
RE: [Repeater-Builder] Running a Mastr II Repeater QRP
I don't know the current frequency, but suspect it's in the 460/465 MHz range. Will it move down into the 440s without a lot of grief? Yes. Also, I don't need anywhere near 100 watts, and need to avoid abusing the good nature and power bill of my landlord. (Also hope to have battery backup.) Can the 100-watt UHF PA be jumpered from an intermediate stage to the filter, bypassing the final? I seem to recall these would run at something in the 10-25-watt range with such a mod. The driver is 40 watts, just bypass the final board. But if you're really trying to safe your landlord's electric bill, the ferro power supply is really what you should be eliminating. That's a real beast of a vampire. Or, is this just gross overkill for a local repeater, and the Mitrek-based idea more appropriate? I'd go with the M2, hands down. --- Jeff WN3A
RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek?
Thanks guys. Looks like this radio might work; need something for a 6-meter beacon transmitter. Tried a Mocom but it wasn't functional. Tried a Maxtrac but the carrier was really squirrely even when I tried the various mods, must be due to the PLL instead of crystal-control. Have to see how the carrier sounds on the Mitrek; if it's good I'll have one of the TX channel elements re-crystalled. Been trying to get something for a 6-meter beacon that doesn't cost a fortune, on and off for the past few years between other projects, and finding it a lot more difficult than it was finding a suitable 10-meter beacon transmitter! Learning a lot in the process though, that's a good thing... 73 Jeff KP3FT --- On Sun, 8/29/10, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? To: Repeater-Builder@yahoogroups.com Date: Sunday, August 29, 2010, 12:56 PM Jeff, The reason that most trunk-mount radios are locked is to prevent theft and tampering. The lock has no electrical function. You will need the ubiquitous #2135 key to unlock your Mitrek drawer. You definitely want to open up the radio before applying power to it, so that you can ascertain if the channel elements are in place, and what optional components are installed. Since Motorola shipped two keys with every radio sold, most radio shops will have a drawer full of #2135 keys. If you ask, you will likely get one or two free. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of KP3FT Sent: Sunday, August 29, 2010 9:09 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? Hi, I know it's a dumb question, but after scouring the internet for info, I find everything about locks and replacement keys for Motorolas and other radios, but I still don't know what locking the Mitrek actually does. Does it kill all power to the radio, or disable certain functions? I'm asking because I just acquired a low-band Mitrek that I need to power up and verify its working condition. It doesn't have a control head, so I need to use the front panel pins, but if the radio is locked, I may end up getting nowhere and still not know if it's either the radio that is bad, it is locked out, or I wired it wrong. This is the first Mitrek I've had. Thanks for any help. Jeff KP3FT
RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek?
I'm assuming this is a CW beacon? I would think that whether rockbound or synthesized, you'd probably be best off having the oscillator running all the time and keying RF at a gain or multiplier stage. You might have to do some keying waveform shaping to avoid keyclicks. I'd take a real close look at the output spectra with something capable of catching transients or any spurs that occur during the keying ramps; maybe key it on/off at a rapid rate repeatedly while doing a peak-hold with the SA for a few minutes to look for any anomalies as a first pass. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff KP3FT Sent: Sunday, August 29, 2010 1:16 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? Thanks guys. Looks like this radio might work; need something for a 6-meter beacon transmitter. Tried a Mocom but it wasn't functional. Tried a Maxtrac but the carrier was really squirrely even when I tried the various mods, must be due to the PLL instead of crystal-control. Have to see how the carrier sounds on the Mitrek; if it's good I'll have one of the TX channel elements re-crystalled. Been trying to get something for a 6-meter beacon that doesn't cost a fortune, on and off for the past few years between other projects, and finding it a lot more difficult than it was finding a suitable 10-meter beacon transmitter! Learning a lot in the process though, that's a good thing... 73 Jeff KP3FT --- On Sun, 8/29/10, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? To: Repeater-Builder@yahoogroups.com Date: Sunday, August 29, 2010, 12:56 PM Jeff, The reason that most trunk-mount radios are locked is to prevent theft and tampering. The lock has no electrical function. You will need the ubiquitous #2135 key to unlock your Mitrek drawer. You definitely want to open up the radio before applying power to it, so that you can ascertain if the channel elements are in place, and what optional components are installed. Since Motorola shipped two keys with every radio sold, most radio shops will have a drawer full of #2135 keys. If you ask, you will likely get one or two free. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of KP3FT Sent: Sunday, August 29, 2010 9:09 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? Hi, I know it's a dumb question, but after scouring the internet for info, I find everything about locks and replacement keys for Motorolas and other radios, but I still don't know what locking the Mitrek actually does. Does it kill all power to the radio, or disable certain functions? I'm asking because I just acquired a low-band Mitrek that I need to power up and verify its working condition. It doesn't have a control head, so I need to use the front panel pins, but if the radio is locked, I may end up getting nowhere and still not know if it's either the radio that is bad, it is locked out, or I wired it wrong. This is the first Mitrek I've had. Thanks for any help. Jeff KP3FT
RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek?
Hi, I tried that with the Maxtrac, kept the oscillator on and keyed the TX at the second driver stage, but it was still nowhere close. I know the Maxars are used quite a lot for beacons, but I've had no luck finding one at a reasonable price, so figure to try the Mitrek. It's set now at 49.3 MHz, so it's already not far from the beacon subband. --- On Sun, 8/29/10, Jeff DePolo j...@broadsci.com wrote: From: Jeff DePolo j...@broadsci.com Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? To: Repeater-Builder@yahoogroups.com Date: Sunday, August 29, 2010, 3:48 PM I'm assuming this is a CW beacon? I would think that whether rockbound or synthesized, you'd probably be best off having the oscillator running all the time and keying RF at a gain or multiplier stage. You might have to do some keying waveform shaping to avoid keyclicks. I'd take a real close look at the output spectra with something capable of catching transients or any spurs that occur during the keying ramps; maybe key it on/off at a rapid rate repeatedly while doing a peak-hold with the SA for a few minutes to look for any anomalies as a first pass. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff KP3FT Sent: Sunday, August 29, 2010 1:16 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? Thanks guys. Looks like this radio might work; need something for a 6-meter beacon transmitter. Tried a Mocom but it wasn't functional. Tried a Maxtrac but the carrier was really squirrely even when I tried the various mods, must be due to the PLL instead of crystal-control. Have to see how the carrier sounds on the Mitrek; if it's good I'll have one of the TX channel elements re-crystalled. Been trying to get something for a 6-meter beacon that doesn't cost a fortune, on and off for the past few years between other projects, and finding it a lot more difficult than it was finding a suitable 10-meter beacon transmitter! Learning a lot in the process though, that's a good thing... 73 Jeff KP3FT --- On Sun, 8/29/10, Eric Lemmon wb6...@verizon.net wrote: From: Eric Lemmon wb6...@verizon.net Subject: RE: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? To: Repeater-Builder@yahoogroups.com Date: Sunday, August 29, 2010, 12:56 PM Jeff, The reason that most trunk-mount radios are locked is to prevent theft and tampering. The lock has no electrical function. You will need the ubiquitous #2135 key to unlock your Mitrek drawer. You definitely want to open up the radio before applying power to it, so that you can ascertain if the channel elements are in place, and what optional components are installed. Since Motorola shipped two keys with every radio sold, most radio shops will have a drawer full of #2135 keys. If you ask, you will likely get one or two free. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of KP3FT Sent: Sunday, August 29, 2010 9:09 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? Hi, I know it's a dumb question, but after scouring the internet for info, I find everything about locks and replacement keys for Motorolas and other radios, but I still don't know what locking the Mitrek actually does. Does it kill all power to the radio, or disable certain functions? I'm asking because I just acquired a low-band Mitrek that I need to power up and verify its working condition. It doesn't have a control head, so I need to use the front panel pins, but if the radio is locked, I may end up getting nowhere and still not know if it's either the radio that is bad, it is locked out, or I wired it wrong. This is the first Mitrek I've had. Thanks for any help. Jeff KP3FT
Re: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek?
Hi Mike, Thanks for the links. The second link was in fact the first webpage I read and bookmarked yesterday. Ton of good info, plus I found a PDF service manual online. The keys page link didn't work, and then I ran across this Yahoo group so I joined to get advice. Still have some questions on bypassing the antenna RX/TX relay, but will cross that bridge when I get the top cover off and get it to transmit. --- On Sun, 8/29/10, Mike Morris wa6i...@verizon.net wrote: From: Mike Morris wa6i...@verizon.net Subject: Re: [Repeater-Builder] dumb question: what is purpose of lock on Mitrek? To: Repeater-Builder@yahoogroups.com Date: Sunday, August 29, 2010, 6:46 PM At 09:09 AM 08/29/10, you wrote: Hi, I know it's a dumb question, but after scouring the internet for info, I find everything about locks and replacement keys for Motorolas and other radios, but I still don't know what locking the Mitrek actually does. Does it kill all power to the radio, or disable certain functions? I'm asking because I just acquired a low-band Mitrek that I need to power up and verify its working condition. It doesn't have a control head, so I need to use the front panel pins, but if the radio is locked, I may end up getting nowhere and still not know if it's either the radio that is bad, it is locked out, or I wired it wrong. This is the first Mitrek I've had. Thanks for any help. Jeff KP3FT http://www.repeater-builder.com/keyspage/keyspage-index.html Please don't solder to the front connector pins. Get hold of a matching connector and solder to that. Please go to this web page at http://www.repeater-builder.com/mitrek/mitrek-index.html and scroll down to the Low Band section and read the articles on 6m mods. Then scroll down to the Non-RF section and read the two articles titled Interfacing the Mitrek mobile radio to your repeater controller and Karl AK2O and the Spokane Repeater Group have a different take on converting the Mitrek. Both have good info on interfacing (i.e. connecting to the radio) and mounting/cooling. Mike WA6ILQ
RE: [Repeater-Builder] Re: Intermod Calculation
The deviation is 15 kHz, or you're seeing 15 kHz of bandwidth on the spectrum analyzer? The latter would be normal, the former wouldn't be. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tim Sawyer Sent: Saturday, August 21, 2010 1:33 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Intermod Calculation I haven't noticed a hum. There's more of a scream on it. It's POCSAG. Is that analog? The dev is basically 15 Khz but there is, what I going to call splatter that is like 30 Khz. -- Tim :wq On Aug 21, 2010, at 10:14 AM, MCH wrote: Many times (but not all), there will be a grungy sound with the spur. Think of a very loud 60 cycle hum. And 15 kHz is higher than normal. I think the typical shift is 5 kHz (+/- 2.5 kHz) if we are talking about digital paging. Analog might be 15 kHz, as the bandwidth limit would be 16 kHz. Joe M. Tim Sawyer wrote: I'm not sure what you mean by grungy. What are you getting at? -- Tim :wq On Aug 21, 2010, at 6:59 AM, MCH wrote: Does it have a 'grungy' sound to it when you hear it on your input?
RE: [Repeater-Builder] Intermod Calculation
Before we get into the math, an important question that needs to be answered is whether or not this mix occurs when your repeater transmitter is unkeyed. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Tim Sawyer Sent: Friday, August 20, 2010 6:36 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Intermod Calculation I have paging intermod from 157.740 Mhz. My receiver is on 144.540 Mhz. I'm 100% sure there is another transmitter involved in the mix because sometimes the pager is transmitting and I have no interference. I have an intermod calculator program but it wants all the known transmitters and the target receiver. But I need to solve for an unknown transmitter. Is there a way to calculate the other possible soruce(s)? -- Tim :wq
RE: [Repeater-Builder] Celwave CC460-A circulator
The simplified instructions for tuning an isolator are: 1. Tune input (tx port) for maximum return loss with antenna port terminated in 50 ohms and reject load connected to reject port 2. Tune output (antenna port) for minimum insertion loss, sweeping from tx port to antenna port, again with reject load connected to reject port 3. Tune reject port for maximum isolation (i.e. best match into load), sweeping from antenna port to transmitter port, adjusting for minimum amplitude 4. Repeat. If you're trying to use it far from its design frequency, you may not get it to meet spec, or you may find that the return loss maximum in step #1 doesn't align well with insertion loss minimum in step 2, or other similar performance problems. The Celwaves usually tune over a fairly broad range, so I think you have a good chance of having it work right, assuming you have the right test equipment to tune it. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of cruizzer77 Sent: Wednesday, August 18, 2010 3:19 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Celwave CC460-A circulator Does anyone have a datasheet or tuning instructions for this kind of circulator? It's a single stage with 3 adjustment screws and right now the sticker says it's on 420 MHz and I would like to know how I get a working range from 430 to 440 MHz. If somebody can explain without the doc this is fine as well. 73 Martin
RE: [Repeater-Builder] Coax length, etc.
But why? If all of the power (or, let's hope, at least 99.99% of it) is on-channel, *should* a properly-designed and properly-functioning transmitter misbehave due to the poor match a duplexer presents at frequencies far removed from the channel center? Well yes, properly designed transmitter. But how much do you want to pay for it? Me personally? I'll pay for a transmitter that works, and works right. The way I see it, repeaters are like cars. You have to get your car inspected for safety. Your car doesn't pass safety inspection? You can't drive it on the public roads, lest you'd be putting other people at risk. Same with a repeater transmitter. If it's unstable and has the potential for causing interference other systems (ham repeaters, public safety, aviation, etc.), it shouldn't be on the air. Either fix it, or if you can't afford to fix it, take it down. I don't want some scmuck driving a beat-up 1972 pickup down the interstate in front of me and having his rear bumper fall off any more than I want somebody putting some clunker up on a mountantop and having it go spurious and interfering with EMS or ATC. That's just the way I see it, sorry if that rubs some people the wrong way. A built in isolator will solve all of those problems as an example. Maybe. An isolator will help flatten the load on, and around, the carrier frequency, but isolators, too, have a finite VSWR bandwidth, they won't provide a perfect load across the entire spectrum. And if you can afford an isolator, you can probably afford a better PA. It is almost impossible for a high Q cavity to not present some reactance away from the tuned frequency. It's not almost impossible, it's definately impossible. If it didn't then it would not have any selectivity. Right. The random length cable of course transforms that reactance to something that the transmitter may or may not be comfortable with as discussed above. Just to clarify, the complex Z is being transformed (both R and jX), not just the reactive component. The thing with random-length cables is just that - they're random. How do we know what cable length is going to make the transmitter happy? Does the transmitter like more XL or more XC, or bigger R's or smaller R's, and at what frequency, because as I'm sure you know, the complex Z is going vary wildly at different frequencies, due to the duplexer's Z, its behavior as a transformer with respect to the load Z at the antenna port, the antenna feedline acting as a transformer with respect to the antenna feedpoint Z, and the cable between the PA and the duplexer also acting as a transformer, so you end up with this complex system of cascaded transformers. Chances are if the PA is that picky, its behavior may also change with temperature, voltage, who knows what else. Antenna feedpoint Z's change with environmental conditions (precipitation, icing, etc.). Feedline electrical lengths (phase) change with temperature, so the resulting Z at the duplexer antenna port is also going to change. There are *so many variables* that will constantly be changing over time that what may seem to work when you walk off the site may fail miserably months, days, maybe even hours later after you think you've found that magic cable length. At least with an isolator we've taken the bulk of those external variables out of the equation - I can agree with that. But, call me a fundamentalist, I still believe that a PA should work, and work right, when it sees 50 ohms on-channel no matter what's happening off-channel. --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
Actually I think that even though Service Monitors have finally become *relatively* commonplace in the Ham Shack, the VNA is not something most hams have seen or know how to use. For $100, Rick's (Amtronix) return loss bridge is a must-have for anyone that has a SM with a SA/TG. With it, there's no longer any excuse for not being able to tune cavities properly for maximum return loss. Like Service Monitors used to be before the flood of HPs on eBay in the last few years, I hear rumors of great deals on VNAs, and yet never see them in any way plentiful, easy to acquire, or affordable, but then again I'm also not exactly looking that hard, and perhaps I'm missing one of those everyone knows about Bob's VNA Warehouse! kinds of sources for such things. Hey, I didn't say they were cheap, nor that everybody can or should own one. There's nothing more enjoyable than tuning up a $100 duplexer from Dayton on a $50,000 network analyzer, especially when it's a 3-porter and you don't even have to swap cables around :-) --- Jeff WN3A
RE: Properly designed PAs (was: Re: [Repeater-Builder] Coax length, etc.)
Jeff, out of all the PAs you've seen out there, both commonly used and not-so-common... which ones (in your opinion) are properly designed (when working right)? I think a lot of them, generally speaking, are properly designed. That's not to say that some of them don't have some downsides or specific, recurring points of failure (to wit: the beloved Mastr II output strap connection failure). I'd name manufacturers that are on my $^!+ list, but I'd rather not do that here, but I will say that most of them are the made-for-amateur brands. I've had great luck with just about anything Micor (and, I have to say, significantly better long-term results with Micor over M2, sorry GE fans). Crescend and *newer* TPL amps have been good to me. EFJ CR1010 PA's have also been workhorses. I have this feeling that most, if not all, have various problems... but you've seen a heck of a lot more of them in-service than I have. Well, I dunno, there are probably others on this list in the two-way business that have seen more than me. I do broadcast for a living; I'm generally an RF guy, my interest in repeaters is just a subset of that. I have a bunch of ham repeaters (20-some I think), and maintain a bunch for other individuals/clubs, and have built or maintained many for others over the years, but I'm sure there are others that do two-way on a daily basis that can give more points of reference as far as recurring problems with other brands/models that I'm not as familiar with. I ask, because this is always the kind of mature, well-developed tech I'm looking for. Price is still a factor, but when you find something that just works... it's truly grand in the tech world, for all sorts of reasons that tend to degrade what something was intended to be, vs. what it really ended up being. To me, the cost of the radio hardware is the least of my worries. I'm not saying that to sound like an alpha-hotel. I look at it this way. I've got all of these repeaters to deal with. I have no free time the way it is. When one breaks, that means I have to take a day off work (or away from family, or away from something else) to go deal with it. It probably means a few hundred miles of driving. And, more than likely, if it's a major failure, I'm probably going to have to make a return trip, doubling the time/cost. So do I really want to take a chance on low-grade hardware up front? No way. Whoever said time is money was an idiot. Time is worth inifinitely times more than money. You can make more money. You can even borrow money. Hell, if you were desparate you could even steal money. You can't do any of those things with time. Time is the one resource you can't make more of. And, for me, I've never had enough time to get everything done that I want to get done. Life's too short to waste time on high-maintenance equipment. I'm also curious to see if your recommendations are new gear, or 20+ year old gear. Both. While I still believe the glory days of two-way turned out the best damned equipment ever made, there is still some decent stuff being made today. I really like MASTR II Stations, but I will admit to some consternation over how the PAs *sometimes* act. We've had 'em run for a decade, and we've had 'em pop like light bulbs every few months. With the exception of the PA's, they generally just run. 100 watt UHF M2 PA's have been rather disappointing for me, both with and without matching networks, with or without isolators. 75 watters seem to run forever. Highband and lowband, much fewer problems. I have a bunch of the 200 watt solid state M2 stations, and have pulled them all out (except for one, which is coming out in a week or two), they're just a nightmare to keep all three PA's working all the time. Is the answer to this question the Crescend amps perhaps? I've been happy with them. I have 7 or 8 of the previous-vintage UHF Crescend/Milcoms (the gold-alodined ones that you're probably familiar with) on the air, and they've been fine, running in the 150-175 watt range. I ordered a couple 100 watt highband amps for a local club about a year ago, they seem OK. I have a bunch of their 900 MHz linear amps in use on STL's and they've been solid. I wouldn't hesitate to buy them. How did their acquisition of Vocom affect their quality? They did change their design, and talking to their engineers a few months ago, they're doing some re-designs due to some of the devices they had been using going on EOL, so more changes will be forthcoming. Some of the older pre-Crescend Vocom amps weren't very good. I haven't looked lately, did they mix up the model line and keep the Vocom stuff? They still have the Vocom line which they market as a lower-cost alternative. I like the TPL RXR series because they are extremely simple. They also have one device per board, so in the event that you have a device fail or burn up a collector trace or something, you only have
RE: [Repeater-Builder] Coax length, etc.
I know I'm going to regret stepping into this one, but since when has that stopped me before... Thanks, Gary, for admitting the 43 doesn't measure power directly. What do you mean by measure power directly? If you're talking about comparing a thruline measurement against absorptive/calorimetric techniques, then that's apples and oranges, one is measuring power in a transmission line (either with or without reflections present), the other is measuring power absorbed into a load, big difference. Please clarify what you mean by measuring power directly so at least we're all on the same page. Of course, it is a directional coupler, no argument. That makes it a reflectometer No, it's not a reflectometer, it can't do forward and reverse measurements concurrently. If the meter did as you suggest, then it would show what the voltage and current are at any point in the line, and therefore be able to tell you what the impedance is at that point Not without knowing the phase between the two it couldn't. BTW, my POS Daiwa can show me a 100% reflected condition, just like the Bird. And just like the Bird, it doesn't indicate if that's an open or a short. A Bird isn't a VSWR bridge, it's a directional wattmeter. Yes, it can be used in a roundabout way to measure/calculate VSWR, but it's not a VSWR meter. Sidebar. I grit my teeth when I hear someone on the radio say my SWR meter shows I'm putting out 100 watts. Since when does a SWR meter measure power!???! Do you use your bathroom scale to check your blood pressure? Egads. I'm not taking a stance here (at least not yet) on the relative merits of the Bird 43 or other thruline-type wattmeter line sections or elements, I'm just trying to get a handle on the matter that is the subject of debate... --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
making a living playing blackjack... --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
Jeff, you aren't stepping on my toes at all. Glad to see your comments. OK, good. Since you've never met me, I can assure you, you definately DO NOT want me stepping on your toes, it would be painful. I do have to agree with Kevin that most duplexer manufacturers recommend different cable length trials between the transmitter and the duplexer when full power can not be reached into the duplexer. Ah, but the crux of the matter is that we're not changing the performance of the duplexer, we're just getting the transmitter to transfer more power into the line. Over the years I have been a manufacturers rep for TX-RX, Sinclair and Telewave. All of them recommend the same thing. Again, it's a CYA measure as Kevin pointed out. PA won't make power? Don't blame us, try mucking with the cable length, see if that helps. I am not a transmitter expert but it is my understanding that the problem is not one of the duplexer not presenting 50 ohms at the wanted frequency but the impedance that it presents off frequency to the transmitter finals. Some solid state devices do not like to see high reactance, even off frequency. But why? If all of the power (or, let's hope, at least 99.99% of it) is on-channel, *should* a properly-designed and properly-functioning transmitter misbehave due to the poor match a duplexer presents at frequencies far removed from the channel center? For one thing the reactance causes them to draw more current than normal. Again, why? This may be why you find that tuning for minimum pa current and maximum power out don't exactly agree with one another. I can promise you they almost never do, but that's not any great mystery. You are probably finding a balance between the off frequency reactance and the on frequency wanted load that the finals see. No, that's not it. The off-frequency Z issue is a totally separate topic from the efficiency vs maximum output subject. Let's keep those two topics separate for the sake of this discussion. If you have the duplexer properly tuned to provide 50 ohms at its input port, the transmitter may still not be happy because of the off frequency reactance presented by the duplexer. I disagree. I would accept the notion that the transmitter may not be happy (and I put that in quotes not to mock you, but becuase I can't come up with a better word either) because it is not *properly matched* when looking into a 50+j0 load. This indicates a deficiency in the amplifier; if it were designed and working right, it *should* make rated power when terminated in a 50 ohm load on-channel. Changing the cable length in this case really does nothing for the on frequency load between the duplexer and transmitter, when the duplexer is presenting 50 ohms, but it can change the off frequency impedance transformation that the transmitter sees. Yes, but again, I argue that this all points back to a PA problem. Or the input Z of the duplexer really isn't 50 ohms and the line is acting as a transformer. Detuning the duplexer and or changing cable length to get the transmitter power up is the wrong way to go here. First the transmitter should be optimized into a 50 ohm load. Then optimize the duplexer input for 50 ohms input. Yes, yes, yes, amen! Someone asked about a rule of thumb for transmitter to duplexer cable length. There is none! Yes there is. You take out a tape measure and the distance from the transmitter to the duplexer. You make the cable at least that length. The cable length between multiple cavities is predictable. As an example between two notch cavities; the first notch presents a very low impedance. With a quarter wave line to the next cavity that low impedance is transformed to a high impedance at the input to the next cavity. That high impedance is then presented with a very low impedance of the second cavity. This critical length cable increases the ultimate notch depth because the high impedance that the cable presents and the low impedance of the cavity form a voltage divider. The greater the ratio the better the rejection. 'zactly. When done right, you can pick up close to 6 dB additional net notch depth when cascading notch (or pass/notch) cavities when the intra-cavity cables are cut this way. Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
So will someone post a simple rule of thumb. If you have the option of optimizing cable length from PA to first cavity, IE you haven't made them yet what's the best simple rule of thumb to follow to build them to avoid reactance. 1/2wl if allowed minus coupling loop depth? Or is that past a simple thumb. Also, This will obviously not work well for 220 or 440 or a most vhf repeater setups. So what would the next ideal cable wl be? And so forth. The reason I ask, if your building new cables why not? Answers on here seem to range a lot. There is no simple rule of thumb, and if anybody tells you that there is, ask them how do you account for the unknown-length of coax that's *inside* your transmitter/amplifier before it gets to the antenna jack. --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
OK, I think, for the most part, we're on the same page. I'm cuttin' and trimmin' a lot here... And this is where I believe the duplexer manufacturers are covering their butt. They don't want the problem with complex reactance presented by the duplexer to be their problem. Not that I don't agree, because it's usually the transmitter that is really at fault. I think that last sentence speaks volumes on the matter. Joe Ham buys a new duplexer and hooks it up to his 110 Watt MASTR II repeater and gets 50 watts out the antenna port. He does his homework and realizes that he should only be loosing 29% with the 1.5 dB of insertion loss stated in the paperwork - but he's loosing over 50%. Ah, but is he really *losing* 50 percent in the duplexer, or is transmitter not making the full 110 watts output to start with? Maybe his transmitter is really only delivering 70 watts to the duplexer. Is it an issue of the duplexer's loss being high, or is the problem the transmitter's not making power? Seems to me it's really the latter. The duplexer manufacturer supposedly engineered and tuned it for a 50 Ohm system. Well, kinda. Many duplexers are spec'ed for 1.5:1 (14 dB RL) input VSWR max. Fortunately, I rarely see any that are that bad. I'll gladly trade off a tenth of a dB of insertion loss for several (if not 10 or more) dB of return loss improvement when I'm tuning on the VNA, but some hams are greedy and don't think along those lines when they're tuning... He knows that the cable he connected to the transmitter is good, because when he disconnects the end going to the transmitter port of the duplexer and connects it to his Bird 43 terminated with a good load - it reads 110 watts. Yes, but did he have a second Bird between the Tx and the duplexer when he was measuring power output? That would have told the real story. Now, is the transmitter becoming spurious Now all bets are off. and the cable length being changed in length satisfies the match between the duplexer and transmitter - I don't know... All I can tell you is I have followed the suggestions written in the WACOM manual and it has worked. I had one instance of a ham radio club loosing PA's left and right on their 2M machine. They told me of the situation and I offered to do a little testing. The 110 watt PA would put out 110 watts into a Bird and dummy, but only 45 watts was coming out the antenna port of the duplexer. At the time I didn't own a spectrum analyzer. The repeater wouldn't duplex without desense. I changed the length of the line between the PA and duplexer until I got the power to read about 75 Watts as I remember. That was 13 years and they still have the same PA - no desense either. Out of morbid curiosity, what kind of PA was it? You are changing the VSWR when tuning the cavity closest to the transmitter. Yes, but once you've adjusted that cavity, from that point on, changing the cable length doesn't vary the VSWR. That was my point - changing the cable length doesn't change VSWR. I realize that impedance transformation cannot occur when you have a 50 Ohm cable (of any length) and a perfect 50 Ohm load - but I think you will agree that a duplexer doesn't, in any way shape or form, present a nice 50 Ohm load. Well, it can get pretty damn close. I can send you some VNA plots of duplexers with input Z's well in excess of 30 dB return loss, some approaching the limits of my test equipment. Of course, when hooked up to an antenna instead of being terminated in a precision load, all bets are off, but hey, that's not the fault of the duplexer... Some transmitters just cannot deal with it without some form of matching after the fact - like a Z-Matcher, Isolator, Circulator, or even a critical cable length. I don't like those transmitters :-) GE MASTR II 110 watt 150.8 to 174 MHz PA and WACOM WP-641. Thinking...thinking...no, haven't done that one. Motorola MICOR 150.8 to 162 MHz PA and WACOM WP-641. Yes, have done that combo, several times that I can think of. Actually, one of the repeaters was low-split from the factory (out of Canada) now that I think about it, so that doesn't count, the others were all H split with no PA mods. Didn't do anything special with cable lengths. Hamtronics 45 Watt 2M PA and Sinclair Q-202. Haven't done any Hamtronics. Well, I cannot believe that I'm the only person on this list that has had success with optimizing the length of cable between the duplexer and transmitter/PA. I don't doubt that others have seen positive (or negative) effects from varying cable lengths - I just said I've never had to resort to doing it, using the equipment that I've used, with the equipment tuned the way I've tuned it. I'll get us some tickets for Vegas - Jeff. I think ZZU has the right idea. He's down in MX-land right now, probably sitting on a beach laughing at us working stiffs
RE: [Repeater-Builder] Re: Coax length, etc.
I'm going to take a stab at this, at the risk of possibly stepping on Gary's toes. 1. RF amplifiers in general (not only solid state) don't *have* a 50 ohm source impedance, they're (nominally) designed to work *into* a 50 ohm load. The difference is subtle, but significant. Transmitters aren't classic generators. 2. GE offered the matching network on station PA's for a number of reasons, among them: a) Amplifier circuit designs (solid-state or otherwise) have a finite bandwidth; a tuning network allows for some output matching adjustment b) Ideally the transmitter will be looking into a nice 50+j0 load (assuming that's what it was designed for), but the world isn't perfect, hence the adjustable output matching network to correct for *minor* load mis-match (strong emphasis on minor) c) Although not explictly described in GE's tuning procedures, significant improvement in efficiency can be obtained with proper tuning of the Z-matcher. Tuning for 50+j0 at the input to the Z-matcher is NOT necessarily the RIGHT match! d) To charge more. I'm half-joking on this; I can't say I've statistically seen more or less failures on M2 PA's with or without the Z-matcher, so I'll give this answer half a smiley: .-, 3. As far as Gary's comment about off-channel Z and its effect on transmitters, some sub-par (or damaged) PA's will go spurious when looking into a load that presents a bad match off-channel, even if it presents a nice flat load on-channel. Some manufacturers suggest playing with cable lengths to tame misbehaving PA's. Again, this is a shortcoming in the PA, and I, for one, am not into band-aid fixes for design flaws or defective equipment; I fix (or replace) the PA. When I walk off the site, I want to KNOW the PA is going to be stable in the future as the load changes, because it WILL change... As far as optimium power transfer, anyone that has passed their tech test probably already knows the textbook answer to that question (the maximum power theorem). But that's not really the issue here, is it OM? Again, we have to accept the fact that amplifiers aren't classic generators; we can't just look at the problem from the perspective of power transfer into a 50 ohm load. We have to look at the devices being used in the PA, the networks doing the impedance transformations, the behavior of the amplifier as a whole (including all cascaded gain stages), its behavior as voltages and temperature are varied, and, one of the most important parameters, efficiency. Just to back up a step, let's revisit the textbook answer of optimum power transfer, which again, is based on a classis generator. In such a case, the optimum power transfer is the *maximum* power that is received by the load. Well, in our little RF corner of the power transfer world, it's not that simple. We're not out eek the last watt out of our amplifier - that's not the goal (or at least it shouldn't be). We all know we can sometimes squeeze a fraction of a dB more out of an amplifier by purposefully mis-loading it, but is that a good thing? Does that make it an optimum match? Hell no. Among other things, we need to look at *efficiency*, and plotting that against power output if we want to find the sweet spot. Efficiency is a primary performance metric for RFPA matching, especially when it comes to continuous-duty solid-state RFPA's where heat is your worst enemy. As far as SS VHF/UHF amplifiers go, good RFPA design should dictate that you have adequate hardware headroom such that you're not stressing the devices or any support components to make rated output, so maximum power transfer should be the least of the worries for the tech tuning the equipment. Stability and spectral purity should be a given in a properly-designed RFPA. So the only parameter that should need to be monitored during fine-adjustment at the output is really efficiency/current draw if everything else was done right from the get-go. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of allan crites Sent: Friday, August 13, 2010 5:41 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Coax length, etc. Gary, Perhaps you can give us some examples to illustrate your thoughts. Perhaps you can also explain why GE chose to include a pi network on the output of the HB M-2 base xmtr to match the xmtr output to 50 Ohms, the shunt capacitor values and the series inductor value used. I'm interested to hear your explaination on how you would determine the length of cable needed. AC From: Gary Schafer gascha...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Fri, August 13, 2010 2:36:23 PM Subject: RE: [Repeater-Builder] Re: Coax length, etc. Hi Allan, Do we really care what the output impedance of the transmitter is? Most
RE: [Repeater-Builder] Re: Mirage B-320-G as a Repeater Amp
The amp does fine without the duplexer inline. Full power and it follows the Mirage chart. But I had a thought (that's SCARY) I pulled out my seldom used MFJ 259 and dialed in my output. I plugged it into the duplexer TX side and noted that it reads 39 ohms. I disconnected the remaining two cans and attached a dummy load to the output of the can and still read 39 ohms. I'm not sure what conclusion to take from this. I mean, low tech! What does the dummy load alone read? How about my other question - do you have grunge with the repeater transmitter NOT keyed (i.e. just listening on the local repeater receiver with the repeater transmitter disabled)? Thank you for your best wishes re: my daughter. She has had a tremendously bad week. The high dose chemo has burned her body and worse that I won't share. But she's a sick little 8 year old. http://princessrachael.com Tried to go to the URL but it took me to some other web site and asked me to log in? Again, best wishes. I have a 1 year old and a 3 year old, they're my best buddies, I can't imagine what you're going through. --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
I must have missed some posts - my inbox ran out of space (I'm on the road and not checking email as often as I usually do), so my apologies if I'm asking questions that have already been answered... Allan Crites and I are currently in discussion which will be used as the basis of a RB web article that will explain exactly what is happening, why it happens, and why an 'optimized' cable length can be used to transfer power ending up with the stated loss of the duplexer and have little reflected power toward the transmitter - so long as the duplexer is tuned properly and exhibits good return loss on the frequency it's designed to pass. Maybe I'm not understanding right. Are you saying that by varying the cable length between the transmitter and the duplexer that you can affect the insertion loss of the duplexer? And also that by varying the cable length between the transmitter and the duplexer that you can vary the reflected power on that same line? Please tell me I'm reading this wrong...I've been on the road a long time and working a lot of long hours, so it's quite possible... --- Jeff WN3A
RE: [Repeater-Builder] Re: Mirage B-320-G as a Repeater Amp
The grungy audio isn't related to the amp. Yes, I know, you said that. My question was whether the grunge was there whether or not the repeater transmitter was keyed. The TKR may be turned down to 20-30 watts and not trip the amp. By not trip, do you mean not key or not cause the amp to fault? I'm guessing the latter. What power output do you measure at 20-30 watts drive? The amp may easily be made continuous duty by driving it at a lower level and adding fans and blowing on it from an inch or so away, or by sucking on it. For the heck of it, I looked at Mirage's specs on their web site. They have a handy-dandy chart showing power in to power out. They're showing that with 25 watts of drive it puts out 165 watts. Doubling the drive to 50 watts, it puts out 200 watts. In other words, a 3 dB increase in drive is yielding only a 0.8 dB increase in output. That tells me you're way into saturation at 200 watts output. Now, saturation in class C is generally a good thing, but that's kind of pushing it. Looking at the power saturation profile, it seems to me that somewhere in the 150-175 watt range is really where that amp would seem to want to be run. And that's based on the intermittant mobile/HT kind of use it was designed for. I think you're only asking for trouble trying to run that amp continuous duty at 20-30 watts of drive no matter how much forced air cooling you push through the fins. We know that the repeater, amp and antenna play nicely and show a 1.1:1 SWR. It's just the duplexer and it appears that the tuning was not done based on the reference I was given earlier. But you said that the VSWR from the amp to the duplexer shows 1.1:1 and the cans are tuned right on the money, so why do you think the duplexer is the problem? Yes, it's a G6-144 and I typed in a state of near exhaustion. I'm living in a children's hospital with a seriously ill daughter. My best wishes for your harmonic. Again, without being there with a spectrum analyzer, it sure sounds like your Mirage is off wandering in the weeds. There's more to building a repeater-grade amplifier than just being able to make gobs of power... --- Jeff WN3A
RE: [Repeater-Builder] Mirage B-320-G as a Repeater Amp
Before adding a Mirage 320 our TKR 750 was putting out 50 watts into a 6 cavity Wacom WP-642 at the cost of 2-3dB loss on TX (as the spec sheet said.) The cans are tuned right on the money and the Hustler G5-144 fed with LMR-400 is 1.1:1. I'm guessing that's a G6...? This has worked for over a year just fine (except for grungy weak signal audio.) Is that grungy weak signal audio with the repeater transmitter keyed, unkeyed, or both? Now add the Mirage B-320-G 200 watt amplifier. Egads. If you have problems without a high-power amplifier, seems only prudent that you should deal with those issues first... Unless I'm mistaken, the B-320G isn't a continuous-duty amp, is it? But as soon as we tune it all up and connect it to the duplexer the Mirage SWR/Drive trips and the amp goes to sleep. A SWR meter between the repeater and the amp shows 1.1:1. The amp to the duplexer shows 1.1:1. How do you know the VSWR is 1.1:1 between the PA and the duplexer if the amp shuts down before you can measure it? In other words, how do you know the amp isn't shutting down because it's going spurious, resulting in high reflected power coming back from the duplexer, tripping the VSWR overload? At the risk of disparaging a particular manufacturer in a public forum, my experience with Mirage repeater amps has been horrific. I wouldn't expect the results of one of their non-repeater amps pressed into repeater service to be any better... Before we go spelunking into the dark underworld of making your Mirage play nice, let's work on fixing your original noise problem. Start by answering the above questions and we can go from there... And for the love of John, get rid of the LMR400 before this turns into a Holy War. --- Jeff WN3A
RE: [Repeater-Builder] Coax length, etc.
The cable length issue is a brother to if you don't like your VSWR, change the point along the transmission line where you're measuring it. I don't know what that's supposed to mean. The VSWR on the line is the same no matter where along the line you measure it. If you're using a meter that reads a different VSWR depending where on the line you put it, you need a new meter... --- Jeff WN3A
RE: [Repeater-Builder] Measuring duplexer insertion loss
Can somebody please explain how the insertion loss of a duplexer is properly measured using a HP 8920A (with specan). 1. Connect duplexer Tx port to duplex port on 8920. 2. Connect antenna port on duplexer to antenna port on 8920. 3. Go to spectrum analyzer screen. 4. Set center frequency = repeater tx frequency 5. Set generate mode to TRACKing 6. Set input to ANTENNA 7. Set generate port to DUPLEX 8. Set generate level to 0 dBm 9. Set the sweep span to something reasonable, like 500 kHz. 10. By default, the marker should be at the center graticule, which should be the Tx frequency you entered in #4 above (if not, go into the marker menu, and set the marker to 5.00, which is the center of the display). The difference between the marker level and the generated level is the loss, minus your cable losses. For example, if you're generating 0 dBm, and the amplitude at the marker is -2.10 dBm, and you have 0.5 dB of patch cable loss, the insertion loss through that leg of the duplexer is 1.6 dB. Repeat the same test for the Rx leg of the duplexer by moving the cable from the Tx port to the Rx port, and changing the center frequency to the Rx frequency. P.S.: Is it correct that a duplexer that has 40 dB isolation in each leg does have 80 dB overall isolation? No. --- Jeff WN3A
RE: [Repeater-Builder] Measuring duplexer insertion loss
Oh, I guess I should have thrown in a couple of generally-applicable guidelines that should go without saying when using ANY sweep gear like this: - terminate the unused port on the duplexer with a high-quality 50 ohm load - it's a good idea to use 6 dB or greater pads on inputs and outputs of the test equipment - use high-quality test cables (double-shielded when you're measuring isolation) - avoid using adapters etc. etc. etc. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Friday, August 06, 2010 4:21 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Measuring duplexer insertion loss Can somebody please explain how the insertion loss of a duplexer is properly measured using a HP 8920A (with specan). 1. Connect duplexer Tx port to duplex port on 8920. 2. Connect antenna port on duplexer to antenna port on 8920. 3. Go to spectrum analyzer screen. 4. Set center frequency = repeater tx frequency 5. Set generate mode to TRACKing 6. Set input to ANTENNA 7. Set generate port to DUPLEX 8. Set generate level to 0 dBm 9. Set the sweep span to something reasonable, like 500 kHz. 10. By default, the marker should be at the center graticule, which should be the Tx frequency you entered in #4 above (if not, go into the marker menu, and set the marker to 5.00, which is the center of the display). The difference between the marker level and the generated level is the loss, minus your cable losses. For example, if you're generating 0 dBm, and the amplitude at the marker is -2.10 dBm, and you have 0.5 dB of patch cable loss, the insertion loss through that leg of the duplexer is 1.6 dB. Repeat the same test for the Rx leg of the duplexer by moving the cable from the Tx port to the Rx port, and changing the center frequency to the Rx frequency. P.S.: Is it correct that a duplexer that has 40 dB isolation in each leg does have 80 dB overall isolation? No. --- Jeff WN3A
RE: [Repeater-Builder] Narrowbanding
Florida Repeater Coordinator proposes narrowbanding: http://www.florida-repeaters.org/FRC%202meter%20narrowband%20p olicy%20released%207-18-10.pdf Apparently Carson's Rule works different in Florida than it does everywhere else. --- Jeff WN3A
RE: [Repeater-Builder] Repeater transmit levels at the receiver?
. --- Jeff WN3A
RE: [Repeater-Builder] Repeater transmit levels at the receiver?
You did an excellent job of explaining the complex interrelationships among 2m repeaters. However, not all 6m repeaters have a 1 MHz split; my 6m repeater on Tranquillon Peak follows the California band plan and has a 500 kHz split. The duplexer has four cans about 12 in diameter and five feet tall. 73, Eric Lemmon WB6FLY Even at 500 kHz split, 100+ dB is more than enough isolation on channel center on 6m. Using simple frequency scaling (not to say that's truly the way to compare, but it gives a rough approximation), that would be like 1.4 MHz split on 2m with the same (100 dB) isolation. 500 kHz on 6m is about 0.9%, still more than twice as much as 0.4% on 2m with 600 kHz split. --- Jeff WN3A
RE: [Repeater-Builder] Repeater transmit levels at the receiver?
At this point, I'm leaning towards the bad mojo/karma phase of the moon! Let's start out with the basics: 1. How much desense do you have? 2. How are you injecting the Rx signal, and what are you using for the signal source? 3. What are you using for a dummy load when doing the desense test? 4. Have you look at both the Tx and the Rx LO to confirm neither are spurious? 5. For the heck of it, have you tried using a totally different Tx and Rx (even just using ham mobile rigs, you have 100 dB of isolation which should make even ham rigs play without desense on the bench, though I'd never use them in production). 6. If do #5, and you still have desense, try flipping Tx and Rx frequencies and see if you still have desense, it might help point to a problem on one side of the duplexer versus the other (e.g. something on the Tx leg generating noise which ceases to be a problem when you're not passing high-level RF through that leg when you have the frequencies flipped). --- Jeff WN3A
RE: [Repeater-Builder] Repeater transmit levels at the receiver?
I wonder how many of the -53 naysayers have or have used a Cushman CE-3? LOL! The folks that have looked at the output of one of these on a spectrum analyzer will get it. K Where I come from, we call that a comb generator, not a signal generator... Ya gotta know the limitations of your test equipment. I recently went several rounds via telephone with a friend of mine who was trying to troubleshoot an apparent desense problem on the bench involving a Mastr II and a 6-cavity DB Products duplexer that I had tuned up for him on the VNA. Long story short, it turned out that when he was doing the desense test using his service monitor (R2600?) as the dummy load and signal source simultaneously that the sig gen would go spurious and result in apparent desense. When he finally did a lossy tee test using an external dummy load, no desense, and likewise when hooked up to the antenna at the site, no desense. --- Jeff WN3A
RE: [Repeater-Builder] Re: Base station coax connector weatherproofing recommendations?
I think you (Skipp) may be confusing 130C with one of the other 3M products. 130C is the self-vulcanizing (self-amalgamating?) tape. It has no adhesive; it's not sticky or gooey; itt doesn't leave any residue. In fact, it doesn't even leave a black stain on connectors like regular vinyl electrical tape; it leaves nothing behind. 3M et al make mastic pads/tapes which, for lack of a better descrption, are like vinyl electrical tape with taffy already attached to one side, with a liner that you remove before applying (i.e. to keep the taffy from sticking to the next layer of tape in the roll. Maybe that's what you're thinking of, Skipp? Even without a courtesy wrap, 130C comes off nice a clean when you slit it with a knife, no muss, no fuss. I've been a big fan/proponent of splicing tape for many years, having been introduced to it by a power plant engineer who showed me how they used it for underground direct-bury high voltage splices. Alternate the 130C with 88, each with an up-down-up wrap, and I've never had a leak. Tape n' taffy is quite effective, and arguably, requires less skill to apply (i.e. I don't force tower crews to use 130C/88 if they're comfortable/trained to do it with taffy), but it's messy if you have to open up the connection, but that can be partially alleviated by using a courtesy wrap. But when I'm doing it myself, I use splicing tape and 88. For the splicing tape I use either 3M 130C or the Plymouth equivalent (can't think of the number off the top of my head). I have a few rolls of the self-fusing silicone tapes that Times, Nashua, Andrew, et al are pushing. It's OK, but I don't see it as being any better than 130C+88. It's a lot more expensive too. Too early to tell how well it holds up to UV, but I would imagine it would do OK. Being silicone, other adhesives (such as vinyl electric tape) don't stick to it well. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of ve7fet Sent: Thursday, July 29, 2010 12:22 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Base station coax connector weatherproofing recommendations? Pulling it back apart isn't an issue with the 130C if you apply it sticky side out. Once you slit down through the vinyl and 130c with a knife, you can peel it apart to open up the splice. Yeah, its a little work to get it to release from the jacket of the cable... but its doing its job keeping the water out. It usually releases from the metal connector parts fairly readily. Lee --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , skipp025 skipp...@... wrote: I lay down a base wrap of decent quality tape before applying the Scotch 130c because I do work for (other) people who very often change their mind. Pulling 130c direct from a connector is a real $#$%* Having a base layer of tape below the 130c can and will make your change order life much happier. s.
RE: [Repeater-Builder] Re: Repeater receiver testing
Kevin, I'm sorry to have to tell you this but I think your calculator batteries need to be changed. 0 dBM = 0.2236 volts in a 50 Ohm circuit. +20 dBM is indeed 100 mW and P=EI and inserting 100 mW into the Eq. for Volts in a 50 Ohm system, E= the sq. rt. of the quantity (.100 x 50) = sq. rt. of 5 = .707 V. or 707 mV. not the 2.24 V. you indicated. I think you blew that one OM. Too much tequila down in XE land perhaps? The square root of 5 is 2.2236 volts, not sure where you got 0.707, that would be square root of 0.5. Kevin was right. Or, to make it even simpler without having to do any real math, +20 dBm is 20 db greater than 0 dBm. 20 dB more than 0.2236 volts is, obviously, 2.236 volts. --- Jeff WN3A
RE: [Repeater-Builder] 420Mhz Radio for Voter?
What is a good radio for building a one way 420 link? The link will be for a remote receiver and will not need to be duplex... RX at the voter and TX at the remote receiver. The link RX has to live on a noisy hill. Thanks for your advice. My preferences, in no particular order, would be Micor/SpectraTAC (low split), Mastr II (77 split), and Delta-S (low-split). MVP/Exec II (again, 77 split) would be fine too. All have excellent front ends. They can be found if you look a bit, especially check Canadian sources; they're not as easy to find stateside as 450-470 radios, but they're not unobtainium either. --- Jeff WN3A
RE: [Repeater-Builder] Re: 420Mhz Radio for Voter?
When you say low split, are you talking about the Motorola TRE1201/TRE8031 406-420 Mhz receivers? I don't have a manual in front of me, but yes, 406-420 receivers, they'll work fine well into the mid 430's without mods. What Canadian sources might have these? Well, Spantek comes to mind as a dealer. CW Wolfe used to get a lot of stuff out of Canada, but I haven't talked to Bud in quite a few years, not sure if he's still in business. This list is probably the best resource. eBay as an alternative. If you get desperate I still have a few dozen low-split Micors in the warehouse, but really don't have the time (or patience) to deal with packing and shipping radios for what few dollars I'd get out of them (i.e. value of my time $value of radio). But if you just wanted a receiver, you can consider me a last resort if you strike out everywhere else... --- Jeff WN3A --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Jeff DePolo j...@... wrote: What is a good radio for building a one way 420 link? The link will be for a remote receiver and will not need to be duplex... RX at the voter and TX at the remote receiver. The link RX has to live on a noisy hill. Thanks for your advice. My preferences, in no particular order, would be Micor/SpectraTAC (low split), Mastr II (77 split), and Delta-S (low-split). MVP/Exec II (again, 77 split) would be fine too. All have excellent front ends. They can be found if you look a bit, especially check Canadian sources; they're not as easy to find stateside as 450-470 radios, but they're not unobtainium either. --- Jeff WN3A
RE: [Repeater-Builder] Re: Repeater receiver testing
Good thoughts Milt, and I'll add a few While not an easy thing to find I would suggest that you most likely need some sort of a bandpass cavity on the receiver to protect from the noise that gets past the heliax notches. Remember that a notch duplexer only removes the notched portion of the TX signal on the RX side and the RX signal on the TX side, all other noise is passed directly to the load. Thus you only have two small notches, one at the RX frequency and one at the TX frequency. Everything else is passed. A duplexer specification that often goes overlooked is mid-band isolation; that is, how much isolation there is between Tx and Rx ports mid-way between the Tx and Rx frequencies. For notch-only duplexers, this value is often very low, often less than 10 dB. The effect of low mid-band isolation is that wideband noise or spurs from the transmitter can result in receiver desense, even if there is enough isolation at the operating frequencies. In other words, the wideband noise passes right across the duplexer at frequencies far enough removed from the notches to cause problems. For pass/reject or bandpass duplexers, the mid-band isolation will be substantially higher, may be somewhere in the range of 30 to 60 dB depending on band, offset, number of cavities, etc. Mid-band isolation is often quoted in manufacturer's specs as a simple scalar value, if it's given at all. Quite often they just give you isolation, and that's just at the Tx and Rx frequencies proper; it doesn't tell you anything about what's happening at other frequencies. A swept transmission response across a broad range from Tx to Rx port with the antenna port terminated will show the true isolation you're getting. As far as adding a pass cavity to attenuate desense caused by noise or spurs coming from the transmitter, it would most likely be more effective if you put it on the transmitter leg of the duplexer rather than the receiver leg. You probably should also look at the TX signal to check for spurs. Micors are generally pretty clean machines, but keep in mind that lowband repeaters were fairly rare back in the day; I don't know if duplex isolation curves were ever published for lowband Micors (ZZU, you QRV?). For the Mastr II you only needed about 50 dB of carrier supression and a little over 60 dB of noise supression for 100 watts at 1 MHz split. I also have had duplexers that look good with a tracking generator but fail under TX power. And we've all had antenna systems that did the same. And I've had dummy loads that did the same as well; point being, don't rule out a problem in your test equipment... --- Jeff WN3A
RE: [Repeater-Builder] Repeater receiver testing
The holy grail for FM performance testing, which includes adjacent channel rejection measurements, is EIA/TIA-603. I believe revision C is the latest. Unfortunately, you'll have to pay to get a copy of that document unless you can scrounge one up. To summarize how the test is done (and I'm doing this from memory, so someone please verify/correct me). 1. You need a way to sum the output of the two sig gens together such that they are properly isolated from each other, and done in such a way that the amplitudes can be calculated accurately at the output of the summing device. 2. You start out by measuring the 12 dB SINAD of the receiver with only the on-channel signal generator active (standard SINAD test, 3 kHz deviation, 1 kHz tone, typically measured at the speaker terminals after deemphasis/filtering/etc.). Simple enough. 3. Increase the RF level of the on-channel generator 3 dB higher than the 12 dB SINAD sensitivity value you found in step 2. This will push the measured SINAD up higher than 12 dB obviously, that's what's supposed to happen. 4. While still generating the on-channel signal, now also generate a signal on the adjacent channel, modulated by a 400 Hz tone at 3 kHz deviation. 5. Increase the level of the adjacent-channel signal until you degrade the SINAD reading of the on-channel signal back down to 12 dB (remember, it was something greater than 12 dB, because you had increased the RF level by +3 dB before you started introducing adjacent-channel dinterference). 6. The difference (in dB) between the offending signal and the 12 dB SINAD sensitivity measured in step 2 is the adjacent channel rejection ratio. So, for example, if the 12 dB SINAD sensitivity was measured at -117 dBm in step 2 without any interference, and you were back down to 12 dB SINAD in step 5 when you had the interfering signal cranked up to -30 dBm, the adjacent channel selectivity would be 87 dB. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of tahrens301 Sent: Saturday, July 24, 2010 10:27 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Repeater receiver testing I have this lowband Micor receiver that I want to test for adjacent channel rejection. I have two calibrated signal generators and a calibrated spectrum analyzer if I need it. How can i measure the rejection of the off channel signal? Thanks, Tim
RE: [Repeater-Builder] Re: Repeater receiver testing
Hi you beat me to it, I would suggest a duplexer problem as -55dB isn't a lot you should have ideally better than 80dB. It also could be the fact that you are running too much tx pwr, have you tried dropping it down. 73 Steve, M1SWB(UK) He said he measured the Tx carrier at the Rx port of the duplexer at -55 dBm; he didn't say he had 55 dB of isolation...
RE: [Repeater-Builder] Re: Repeater receiver testing
Hi Jeff yes I know -55db is I think around 399 microvolts No, you're still missing it. He said -55 dBm (m = milliwatts), not -55 dB. which will flatten any receiver -55 dBm at 1 MHz offset isn't going to bother any half-decent receiver. A decent receiver would have 100 dB of adjacent-channel selectivity (that would be 20 kHz away on lowband), so if we assume the sensitivity is -117 dBm (0.3 uV), it should tolerate a signal int the vicity of -17 dBm at only 20 kHz away with only slight degradation. At 1 MHz away, a good lowband receiver with a real front end will tolerate much, much more, probably on the order of 0 dBm (over 2/10ths of a volt). 80 watts TPO = +49 dBm. He's measuring -55 dBm at the receive port, so he has 104 dB of carrier supression, way way way more than is necessary for a Micor at 1 MHz split. --- Jeff WN3A
RE: [Repeater-Builder] Repeater transmit levels at the receiver?
Ok, now I hook the spectrum analyzer up to the receiver port, and I see about -55dBm. 50 watts = +47dBm, minus the 100dB notch = -53dBm that is pretty close to what I'm seeing at the rx antenna port. Question is: Should this good enough for a low band micor receiver? Thanks, Tim W5FN Yes, should be good enough for even 500 kHz split. However, at close tx-rx offsets, transmitter noise is often more of an issue than carrier supression, so test your duplexer backwards to make sure you have the same isolation in the other direction. And don't forget the noise foor on 6m is usually pretty high, so even if you have a trace of desense on the bench using a dummy load and lossy tee, you may not even notice it in the field. --- Jeff WN3A
[Repeater-Builder] (Ware)house cleaning - connectors, radios, etc.
Continuing to consolidate three warehouse/storage locations and getting rid of some excess in the process. I posted some of these on another list but still have a lot left, posting them here with ham discounts. Qty 60+ RFS/Cablewave 738801 1/2 N female, NOS, military packaging (fits Andrew LDF4, RFS FLC12 and LCF12 and most other 1/2 non-Superflex cables) - $7 ea Qty 6 Andrew H7PNF - N female, silver-plated, for HJ7-50 1-5/8, NOS - $75 ea Qty 100+ Andrew F2PNM N male connector, silver-plated (fits Andrew FSJ2, RFS SFC38 and other 3/8 Superflex), NIB - $8 ea Qty 20+ Andrew L5NF N female for LDF5-50 7/8 (fits RFS FLC78, LCF78, and others too), NIB - $15 ea Qty OTW - Used 1/2, 7/8, 1-1/4, 1-5/8 connectors, foam, air, Superflex, type N, DIN, EIA flanges, etc. - let me know what you need Qty 40+ Andrew SGL12-10B2 ground kits, clip-on type, NIB - $9 ea Qty 10+ Mastr II 44 cabinets - $50 each PICKUP ONLY Qty 20+ Mastr II stations, mostly UHF, some with IDA controller, various power levels up to 200 watt solid state, with or without cabinets, starting at $200 PICKUP ONLY Qty 100+ Micor, Mastr II, Exec II, etc. mobiles, various bands/power levels, boxes of parts/boards/etc. PICKUP ONLY, you pick through the stacks, prices vary. 20+ Motorola SpectraTAC coded squelch (PL) modules - $25 each 500+ GE/Moto/EFJ/etc. channel elements/ICOM's/crystal modules, all flavors, all bands - let me know what you need, prefer to sell in substantial quantities. 150? Motorola Vibrasponder paging reeds, $50 for all Abbreviations: NIB - new in box/bag NOS - new, old stock (may have signs of having been in storage a while, dirty/dusty package, etc.) OTW - out the wazoo All items shipped either USPS or UPS at-cost plus $5 packing charge regardless of quantity. Pickup only items located in Philadelphia area. Will consider trades - only thing I can think of I need right now are long runs of new 1/2 line (Andrew or RFS, no Superflex), 1/2 ground kits, and/or 1/2 hoisting grips. Please reply direct. Thanks. --- Jeff WN3A
Re: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM
It appears my L button doesn't work half the time, guess I need to take my keyboard apart and clean it. Jeff On 7/16/2010, kb1sph kb1...@wqex694.info wrote: Ok, I'm playing around with my Kenwood TKR-820 a bit. I've found the instructions for HEX editing the channel and ctcss information after reading it from the EEPROM, and they work great. But there's nothing about DCS. I'm wiing to try and decipher how to get the DCS, but I need a look at the information from a chip that contains DCS information. Since I don't have a real programmer I can't change mine and then look at it. So if anyone has a TKR-820 with DCS in it and a EEPROM reader, it would be greatly appreciated if you are wiling to read the chip with PonyProg2000 (http://www.lancos.com/ppwin95.html) and send me a copy. Thanks, Jeff, KB1SPH / WQEX694 Yahoo! Groups Links
Re: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM
Ok, let me make it a little more clear for anybody that might not have understood the first message. (No offense intended Eric) A Kenwood TKR-820 repeater has CTCSS and DCS encoding and decoding built into it with an on-board controller. The configuration is stored in a EEPROM chip, 93C46 (or 93LC46). What I'm trying to do is figure out how to change the configuration without using the expensive Kenwood programmers, unfortunately this one isn't just a simple cable. I have a serial EEPROM reader/writer, so I used instructions found in the repeater-builder archives at http://www.mail-archive.com/repeater-builder@yahoogroups.com/msg63481.html to modify the configuration for the ctcss tones. Unfortunately, the person who wrote that article didn't figure out the DCS configuration. So I'm hoping that someone who has a TKR-820 already configured for DCS has the ability to read the EEPROM chip as well and send me a copy. I hope that clears it up a little more. Jeff, KB1SPH / WQEX694 -- From: Eric Lemmon wb6...@verizon.net Sent: Thursday, July 15, 2010 10:24 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Jeff, I suspect you may be headed for disappointment. CTCSS (PL) and CDCSS (DPL) are handled differently within the radio. While the former is audio, albeit sub-audible, the latter requires a DC connection to the modulator in order to create the DCS signal at a 134.4 Hz rate. In other words the CTCSS hardware will not work for CDCSS. Perhaps some readers who have TKR-820 stations with CDCSS capability can advise you about the modifications and/or optional modules that are necessary to handle DCS. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of kb1...@wqex694.info Sent: Thursday, July 15, 2010 7:03 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Ok, I'm playing around with my Kenwood TKR-820 a bit. I've found the instructions for HEX editing the channel and ctcss information after reading it from the EEPROM, and they work great. But there's nothing about DCS. I'm wiing to try and decipher how to get the DCS, but I need a look at the information from a chip that contains DCS information. Since I don't have a real programmer I can't change mine and then look at it. So if anyone has a TKR-820 with DCS in it and a EEPROM reader, it would be greatly appreciated if you are wiling to read the chip with PonyProg2000 (http://www.lancos.com/ppwin95.html) and send me a copy. Thanks, Jeff, KB1SPH / WQEX694 Yahoo! Groups Links
Re: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM
Well I'm not particularly needing any one code at the moment, just trying to figure out how exactly to figure out the hex codes. Thanks for the great tutorial on the rest. It makes it easy to change the config when I want instead of having to call someone with a programmer. Now if I can find a connector that goes into the socket on top of the display board I could just wire up a connection to the ICSP connector on my board and make it easier for the frequencies. This information should be put on the repeater-builder web site if it's not already. I couldn't find it, but maybe I didn't look close enough. Jeff, KB1SPH / WQEX694 -- From: DCFluX dcf...@gmail.com Sent: Friday, July 16, 2010 12:35 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Hey, I didn't need DCS at the time. Looks like TX code is at 80-81 Hex, and RX code is 82-83 81 EC = D023N 81 E6 = D026N What DCS code do you need? On Thu, Jul 15, 2010 at 8:46 PM, Jeff Lavoie - KB1SPH/WQEX694 kb1...@wqex694.info wrote: Ok, let me make it a little more clear for anybody that might not have understood the first message. (No offense intended Eric) A Kenwood TKR-820 repeater has CTCSS and DCS encoding and decoding built into it with an on-board controller. The configuration is stored in a EEPROM chip, 93C46 (or 93LC46). What I'm trying to do is figure out how to change the configuration without using the expensive Kenwood programmers, unfortunately this one isn't just a simple cable. I have a serial EEPROM reader/writer, so I used instructions found in the repeater-builder archives at http://www.mail-archive.com/repeater-builder@yahoogroups.com/msg63481.html to modify the configuration for the ctcss tones. Unfortunately, the person who wrote that article didn't figure out the DCS configuration. So I'm hoping that someone who has a TKR-820 already configured for DCS has the ability to read the EEPROM chip as well and send me a copy. I hope that clears it up a little more. Jeff, KB1SPH / WQEX694 -- From: Eric Lemmon wb6...@verizon.net Sent: Thursday, July 15, 2010 10:24 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Jeff, I suspect you may be headed for disappointment. CTCSS (PL) and CDCSS (DPL) are handled differently within the radio. While the former is audio, albeit sub-audible, the latter requires a DC connection to the modulator in order to create the DCS signal at a 134.4 Hz rate. In other words the CTCSS hardware will not work for CDCSS. Perhaps some readers who have TKR-820 stations with CDCSS capability can advise you about the modifications and/or optional modules that are necessary to handle DCS. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of kb1...@wqex694.info Sent: Thursday, July 15, 2010 7:03 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Ok, I'm playing around with my Kenwood TKR-820 a bit. I've found the instructions for HEX editing the channel and ctcss information after reading it from the EEPROM, and they work great. But there's nothing about DCS. I'm wiing to try and decipher how to get the DCS, but I need a look at the information from a chip that contains DCS information. Since I don't have a real programmer I can't change mine and then look at it. So if anyone has a TKR-820 with DCS in it and a EEPROM reader, it would be greatly appreciated if you are wiling to read the chip with PonyProg2000 (http://www.lancos.com/ppwin95.html) and send me a copy. Thanks, Jeff, KB1SPH / WQEX694 Yahoo! Groups Links Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Re: TKR-820 CTCSS/DCS EEPROM
Skipp, sent you a message, but sometimes messages from my domain are put in spam on yahoo. I still haven't figured out why, so if you don't get it in your inbox, check the spam folder. Jeff -- From: skipp025 skipp...@yahoo.com Sent: Friday, July 16, 2010 12:51 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: TKR-820 CTCSS/DCS EEPROM Hi Jeff, I have a few DCS TKR-720/820 Eprom files in my collection. Email me direct if you haven't got it figured out by the weekend. I have a KPT-50, the software and the ponyprog setup you have so I can help as time allows. With that software and an inexpensive EEprom Programmer easily found on Ebay... you can do a lot of neat stuff... like the mentioned. cheers, skipp025 at yahoo.com --- In Repeater-Builder@yahoogroups.com, Jeff Lavoie - KB1SPH/WQEX694 kb1...@... wrote: Ok, let me make it a little more clear for anybody that might not have understood the first message. (No offense intended Eric) A Kenwood TKR-820 repeater has CTCSS and DCS encoding and decoding built into it with an on-board controller. The configuration is stored in a EEPROM chip, 93C46 (or 93LC46). What I'm trying to do is figure out how to change the configuration without using the expensive Kenwood programmers, unfortunately this one isn't just a simple cable. I have a serial EEPROM reader/writer, so I used instructions found in the repeater-builder archives at http://www.mail-archive.com/repeater-builder@yahoogroups.com/msg63481.html to modify the configuration for the ctcss tones. Unfortunately, the person who wrote that article didn't figure out the DCS configuration. So I'm hoping that someone who has a TKR-820 already configured for DCS has the ability to read the EEPROM chip as well and send me a copy. I hope that clears it up a little more. Jeff, KB1SPH / WQEX694 -- From: Eric Lemmon wb6...@... Sent: Thursday, July 15, 2010 10:24 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Jeff, I suspect you may be headed for disappointment. CTCSS (PL) and CDCSS (DPL) are handled differently within the radio. While the former is audio, albeit sub-audible, the latter requires a DC connection to the modulator in order to create the DCS signal at a 134.4 Hz rate. In other words the CTCSS hardware will not work for CDCSS. Perhaps some readers who have TKR-820 stations with CDCSS capability can advise you about the modifications and/or optional modules that are necessary to handle DCS. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of kb1...@... Sent: Thursday, July 15, 2010 7:03 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] TKR-820 CTCSS/DCS EEPROM Ok, I'm playing around with my Kenwood TKR-820 a bit. I've found the instructions for HEX editing the channel and ctcss information after reading it from the EEPROM, and they work great. But there's nothing about DCS. I'm wiing to try and decipher how to get the DCS, but I need a look at the information from a chip that contains DCS information. Since I don't have a real programmer I can't change mine and then look at it. So if anyone has a TKR-820 with DCS in it and a EEPROM reader, it would be greatly appreciated if you are wiling to read the chip with PonyProg2000 (http://www.lancos.com/ppwin95.html) and send me a copy. Thanks, Jeff, KB1SPH / WQEX694 Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] question for commercial radio shops
If everyone using them had a GMRS license (one license covers the family) you could probably get away with using GMRS frequencies, but not FRS. Some part 90 radios were certified for part 95 as well, mostly Kenwood I think. Motorola radios were not part 95 certified usually because of the digital capabilities (MDC, STAR) and Motorola didn't want to sell cheap radios, they're a bit greedy and wanted the big bucks from commercial. Of course, that doesn't stop some of us from using them anyway. In the end, it's up to you, but I would say no to FRS. An alternative may be to find some cheap MURS radios. They are license free and I think they're allowed up to 2 watts as opposed to the 500mw FRS. Also, if they are using bubble pack FRS radios on a channel higher than 7, chances are (if they are made within the last few years) they are just as powerful as the LMR radios. The only difference is usually the antenna, they probably have the equivalent to a stubby uhf antenna on the LMR radios, which does make a difference in range. I really do not think it would help the range too much, unless you're talking about using mobiles, then I would definitely say no to doing it. Jeff, KB1SPH / WQEX694 -- From: Chris Curtis demo...@rollanet.org Sent: Tuesday, July 13, 2010 8:29 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] question for commercial radio shops I pastor a motorcycle ministry and have no problem saying no to illegal or fringe favors from fellow church members. I also try to help them find a legal solution to whatever problem/project they have. Good luck Kb0wlf -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:Repeater- buil...@yahoogroups.com] On Behalf Of KD5SFA Sent: Tuesday, July 13, 2010 7:24 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] question for commercial radio shops If a person whom you knew and is involved in a number of church youth camps activities asked you to program FRS frequencies into a 4w UHF HT type accepted for LMR would you do so ? It would only be for extended range at camp. My gut is to tell him no... Sorry for the slightly off topic postI just need a little extra thought on the subject... Bad thing is the person asking is the captain of my Volunteer FD. 73, Jon Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.441 / Virus Database: 271.1.1/2962 - Release Date: 07/13/10 06:36:00 Yahoo! Groups Links
Re: [Repeater-Builder] Re: question for commercial radio shops
Nothing if you're name is roger. From: Larry Horlick Sent: Tuesday, July 13, 2010 10:02 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: question for commercial radio shops Hey, what's wrong with a roger beep?'beep' On Tue, Jul 13, 2010 at 9:56 PM, skipp025 skipp...@yahoo.com wrote: If a person whom you knew and is involved in a number of church youth camps activities asked you to program FRS frequencies into a 4w UHF HT type accepted for LMR would you do so ? It would only be for extended range at camp. If the radio power can be reduced, turn it down and program the FRS frequencies in. If the power can't be reduced, put the radios on GMRS Frequencies. Many of the Kenwood Portables I sell allow power level programming per channel so the FRS gets low and the other stuff gets the nominal rated power. FRS Radios are sold cheap at the big box stores... try to find the ones that allow you to turn off the $...@%@*% stupid roger beeps s. Emoticon1.gif
Re: [Repeater-Builder] Re: question for commercial radio shops
That would make some interesting research. Honestly I like having my repeater controller do a beep at a lower audio level when someone un-keys. Low enough to be heard, but not be a nuisance. If someone is closer to the repeater you may not know if they've un-keyed until the repeater itself drops out. With a courtesy tone (as they're called now) it lets the other person know you've un-keyed and they can key up again. But I'll admit some of these beeps that the bubble packs and CBs have are really annoying. Jeff, KB1SPH / WQEX694 From: ka9qjg Sent: Tuesday, July 13, 2010 11:02 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: question for commercial radio shops Meant a lot to the First Astronauts with Communications that is how it got started I think , I forget if it was a Pre or after Transmission Don KA9QJG Nothing if you're name is roger. From: Larry Horlick Sent: Tuesday, July 13, 2010 10:02 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: question for commercial radio shops Hey, what's wrong with a roger beep?'beep' On Tue, Jul 13, 2010 at 9:56 PM, skipp025 skipp...@yahoo.com wrote: image001.gif
Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements
George, sent the money. It will come from a different e-mail address, but it will have my name. Jeff, KB1SPH / WQEX694 -- From: George Henry ka3...@att.net Sent: Tuesday, July 13, 2010 1:49 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements I'm only looking to recoup what I have invested in them... $50 for the pair. At the moment, I have lots of spares, but sure, I'll take another set. If you do Paypal, you can pay me at ka3...@aol.com. George, KA3HSW From: Jeff Lavoie - KB1SPH/WQEX694 kb1...@wqex694.info To: Repeater-Builder@yahoogroups.com Sent: Mon, July 12, 2010 10:17:12 PM Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements Actually 462.600 is the frequency I'm currently running my Kenwood on. I would probably be putting the Motorola on the same frequency with a different PL at a different location. That would solve a lot of headaches if you're willing to part with them. I was thinking about doing ham later down the road if GMRS goes away, I'm sure you've all heard about the proposed rule changes. But until I hear that GMRS repeaters are not allowed (or must be narrow band) I'll be setting it up on GMRS. The Kenwood is more set up for a portable repeater for events right now. A group of us get together and help out with events when there aren't enough ham volunteers. Let me know what you want for the channel elements. If you're interested I would be willing to send you a set of channel elements back if you need them as spares. Jeff, KB1SPH / WQEX694 -- From: George Henry ka3...@att.net Sent: Monday, July 12, 2010 1:59 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements What frequencies are you looking for? Ham or GMRS, I presume... I've got a bunch of MSR-2K elements if you need any, including a set for a 462.600 GMRS repeater. George, KA3HSW / WQGJ413 From: Jeff Lavoie - KB1SPH/WQEX694 kb1...@wqex694.info To: Repeater-Builder@yahoogroups.com Sent: Mon, July 12, 2010 1:15:28 AM Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements (and a guacamole recipe) Thanks Skipp, that helps a great deal. I've found a lot of usefule information on repeater-builder.com over the years, but I just finally signed up for the yahoo group yesterday, I don't know why I waited. Bomar sounds like a good place to start with. I got this MSR-2000 for $25 at a hamfest because the guy didn't want to load it up in his truck to take it back home. I was buying a Kenwood TKR-820 and he said, I'll tell you what, I'll give you the pair for $50. How could I go wrong? The Kenwood is working great thanks to repeater-builder.com. On another note, I sent you a message a few days ago, but sometimes yahoo blocks my messagesnot sure why. I was wondering if you had any information about a CSI-32 tone panel and possible firmware upgrades. The EPROM inside has a sticker on it that says the following. 128 v4.0 6289 (I think, hard to read) © CSI - Jeff Yahoo! Groups Links
Re: [Repeater-Builder] Re: question for commercial radio shops
That makes sense. I wonder if the ground crew could trick the ground receiver into un-muting the audio from the shuttle so that they can listen in on what's going on. Jeff, KB1SPH / WQEX694 -- From: Martin Flynn mafl...@theflynn.org Sent: Tuesday, July 13, 2010 11:16 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: question for commercial radio shops Spacecraft systems are full-duplex. The purpose of the Quindar tones was to mute the uplink audio when Houston had nothing to say. ka9qjg wrote: Meant a lot to the First Astronauts with Communications that is how it got started I think , I forget if it was a Pre or after Transmission Don KA9QJ Yahoo! Groups Links
Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements (and a guacamole recipe)
Thanks Skipp, that helps a great deal. I've found a lot of usefule information on repeater-builder.com over the years, but I just finally signed up for the yahoo group yesterday, I don't know why I waited. Bomar sounds like a good place to start with. I got this MSR-2000 for $25 at a hamfest because the guy didn't want to load it up in his truck to take it back home. I was buying a Kenwood TKR-820 and he said, I'll tell you what, I'll give you the pair for $50. How could I go wrong? The Kenwood is working great thanks to repeater-builder.com. On another note, I sent you a message a few days ago, but sometimes yahoo blocks my messagesnot sure why. I was wondering if you had any information about a CSI-32 tone panel and possible firmware upgrades. The EPROM inside has a sticker on it that says the following. 128 v4.0 6289 (I think, hard to read) © CSI - Jeff -- From: skipp025 skipp...@yahoo.com Sent: Sunday, July 11, 2010 10:52 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Recrystal MSR-2000 Channel Elements (and a guacamole recipe) Recrystal MSR-2000 Channel Elements Path_Finder.Geo kb1...@... wrote: Hi everyone, I am going to post this message here because batlabs didn't approve my post. Apparently it's too harsh to tell people, PLEASE DO NOT TELL ME TO HAVE SOMEONE ELSE DO IT. Hi Jeff, Apparently you do not play the BatLabs Game very well? I'm sure you'll survive with the ever so perky bunch over here. I am looking for information on how exactly to re-tune a channel element for a MSR repeater. I've seen instructions as far as what to adjust on the element itself, but what I really need to know is; what equipment is required, how to hook that equipment up to the channel element, and what to look for while adjusting the channel element. The transmit channel element is best adjusted for frequency center by using a Communications Service Monitor setup to sample (off the on-air signal) read the main carrier channel/frequency. The simple way to set the IDC Control/Pot is to set the Transmit CTCSS (PL) Tone deviation to about 750Hz. In a stock MSR-2000 the repeat audio level is then set using the level pot on the Squelch Gate Module. If you don't have access to a Service Monitor, a decent Frequency Counter will at least let you net (adjust) the frequency to F-center (on the desired frequency). If you move the transmitter more than say... 500 kHz from its last alignment location, you should repeat the Service Manual Alignment steps on or near the new frequency. The Receiver is a different animal. Take the Receiver frequency and add and/or subtract the receiver IF frequency (most often 10.7 or 10.8 MHz for the VHF Receiver). The formula you use depends on your receivers IF Frequency and Injection Chain, which translates to which side of the IF the multiplied crystal frequency ends up on. In your example it's probably F-frequency minus the IF Frequency equals the multiplied Channel Element injection frequency, which is what you want to set/align. Put a X1 Scope/Text Probe on your Service Monitor (or Frequency Counter) Antenna (Low Level RF) Input and place it down onto/near the receiver circuit board. You can also use a decent quality frequency counter if you're more careful. At some location on or near the board you will be able to monitor and measure the output of the RX Channel Element Frequency, then set it for the expected Injection Frequency. As an example: A receive frequency of 151.625 MHz minus a 10.7 IF frequency equals 140.925 MHz. Sniff around the receiver board until you observe a signal in that area, then net (adjust) the channel element frequency to the expected 140.925 F-center location. If you can't find the expected frequency you might run the numbers for a 10.8 IF Frequency and sniff around 140.825 for the channel element injection frequency. In both the above examples, a X1 (times-1) Scope Probe or something similar is handy to use. If you can't get/find a signal, make a short antenna probe by clipping a small length of insulated regular wire onto the end of the probe. The end of the wire held by the Scope Probe jaws should obviously be stripped bare. Try not to allow the sampling wire and/or probe to directly contact/short any of the exposed metal parts on the receiver board. Now I realize that I need a new crystal as well, and I realize it can all be done professionally with temperature compensation. Yeah but in many cases professional is a lot more expensive than it really has to be. But what I want to know is how I can do it myself just to get started and make sure everything is going to work the way I want before I pay out big bucks to have it all done the right way. I have an extra set of channel elements, so playing around with one set isn't going to affect having the other set done professionally if I
Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements
Actually 462.600 is the frequency I'm currently running my Kenwood on. I would probably be putting the Motorola on the same frequency with a different PL at a different location. That would solve a lot of headaches if you're willing to part with them. I was thinking about doing ham later down the road if GMRS goes away, I'm sure you've all heard about the proposed rule changes. But until I hear that GMRS repeaters are not allowed (or must be narrow band) I'll be setting it up on GMRS. The Kenwood is more set up for a portable repeater for events right now. A group of us get together and help out with events when there aren't enough ham volunteers. Let me know what you want for the channel elements. If you're interested I would be willing to send you a set of channel elements back if you need them as spares. Jeff, KB1SPH / WQEX694 -- From: George Henry ka3...@att.net Sent: Monday, July 12, 2010 1:59 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements What frequencies are you looking for? Ham or GMRS, I presume... I've got a bunch of MSR-2K elements if you need any, including a set for a 462.600 GMRS repeater. George, KA3HSW / WQGJ413 From: Jeff Lavoie - KB1SPH/WQEX694 kb1...@wqex694.info To: Repeater-Builder@yahoogroups.com Sent: Mon, July 12, 2010 1:15:28 AM Subject: Re: [Repeater-Builder] Recrystal MSR-2000 Channel Elements (and a guacamole recipe) Thanks Skipp, that helps a great deal. I've found a lot of usefule information on repeater-builder.com over the years, but I just finally signed up for the yahoo group yesterday, I don't know why I waited. Bomar sounds like a good place to start with. I got this MSR-2000 for $25 at a hamfest because the guy didn't want to load it up in his truck to take it back home. I was buying a Kenwood TKR-820 and he said, I'll tell you what, I'll give you the pair for $50. How could I go wrong? The Kenwood is working great thanks to repeater-builder.com. On another note, I sent you a message a few days ago, but sometimes yahoo blocks my messagesnot sure why. I was wondering if you had any information about a CSI-32 tone panel and possible firmware upgrades. The EPROM inside has a sticker on it that says the following. 128 v4.0 6289 (I think, hard to read) © CSI - Jeff Yahoo! Groups Links
Re: [Repeater-Builder] CSI-32 (Lynnwood Washington) Repeater Tone Panel Controller Information
Ok, I can get you the date code tomorrow if you find some spare time to check. It's too bad I couldn't get a copy of the original code and maybe modify it myself. I like to tinker around with existing programming a bit, but I wouldn't know where to begin if I were to start from scratch. Jeff, KB1SPH / WQEX694 -- From: skipp025 skipp...@yahoo.com Sent: Monday, July 12, 2010 2:18 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] CSI-32 (Lynnwood Washington) Repeater Tone Panel Controller Information Jeff Lavoie - KB1SPH/WQEX694 kb1...@... wrote: Thanks Skipp, that helps a great deal. I've found a lot of useful information on repeater-builder.com over the years, Hi Jeff, Just don't buy a car from any of us and you'll be fine. I was wondering if you had any information about a CSI-32 tone panel and possible firmware upgrades. The EPROM inside has a sticker on it that says the following. 128 v4.0 6289 (I think, hard to read) © CSI In regards to the CSI (Lynnwood Washington CSI, not the Ventura CA. CSI) brand of Repeater Tone/DCS Controllers. The latest firmware version is based on the PC Board date of construction, which is most often silk screened in white ink right on the board. V4.0 was one of the last firmware versions available for most of the CSI-32 Controllers. As time allows I could check my files for firmware information but I would need to know your pc board date code in addition to all the other details. Right now I'd say the 4.0 stuff is pretty much it in regards to updates. cheers, s. Yahoo! Groups Links
RE: [Repeater-Builder] VHF REPEATER USING DELTA or RANGR
They're great radios. I'd strongly recommend a Delta-S (narrowband front end) over a wideband SX or Rangr due to the front end being much tighter. I have many UHF Delta-S's (probably about 60 or 70) on the air, mostly for aux links, and have set up VHF and UHF Deltas as repeater radios, packet nodes, etc. as well. I'd recommend sticking with a low-power radio, and driving an outboard amp if you need significant power. What I usually do is take low-power PA's and transplant them onto the larger heatsink of a high-power radio, run them at low power (like 15 watts or less), and drive an outboard PA. With the big heatsink, no fans required. The highband and UHF radios are extremely stable PA-wise, you can turn them down without a problem. Lowband is another story...they get squirrelly at low power, especially when used out-of-band on 6m. I have probably 50 pages' worth of notes covering all kinds of mods, measurements, etc. that I've done on Deltas over the years, and know them inside-out, so email if you have any specific questions. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of tomnevue Sent: Thursday, July 08, 2010 10:54 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] VHF REPEATER USING DELTA or RANGR Has anyone made a VHF repeater using 2 Delta or Rangr radios? Were the results OK? Any unexpected problems? Tom
RE: [Repeater-Builder] Proto boards
Vector Electronics (Google vectorbord and circbord, not typos), GC Electronics, and Radio Shack (if you can find a store still stocking them). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Ralph S. Turk Sent: Tuesday, July 06, 2010 3:17 PM To: Repeater-Builder Subject: [Repeater-Builder] Proto boards Hi All Looking for small etched, maybe drilled, small boards with layout for several transistors, resistors etc all isolated pads Also looking for ones that have layouts for 8pin, 14 pin or 16 pin dip with isolated pads for hook up I have some misc of the above and they are great for inverters, buffers, little op amps for increasing the level of the disc or tx audio. Any ideas? Ralph
RE: [Repeater-Builder] MASTR II LOW BAND TUNING
I took a quick look at them, and what stands out like a sore thumb is 1.6 db insertion loss with a 150 watt power rating. That means they'll be dissipating close to 50 watts in such a small package. Doesn't give me a warm and fuzzy feeling... --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Monday, July 05, 2010 8:02 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] MASTR II LOW BAND TUNING I see what the sales flyer says, but the response plots show no real bandpass action. Indeed, the plots depict exactly how a notch-only duplexer responds. In fact, the plots look faked, IMHO. I have tuned many duplexers over the years, and none of the plots look so perfect. If Fiplex duplexers are so great, why aren't they used by large state patrol systems? Is there a list of satisfied customers? Maybe I'm just too cynical, but I think the specs for those duplexers are just too good to be true. I'm going to keep my money in my pocket until I see some credible evidence that these duplexers perform as advertised. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Joe Sent: Monday, July 05, 2010 4:18 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] MASTR II LOW BAND TUNING The spec sheet shows them to be bandpass/band reject. From the document: These duplexers utilize six high Q (helical) resonant cavities, interconnected in a band pass-band reject configuration which allows close spaced transmit-to-receive frequency operation. Joe On 7/5/2010 6:33 PM, Chris Curtis wrote: They are notch only devices and I've used similar devices using that helical design for years.
RE: [Repeater-Builder] Re: [Repeaters] Looking for HD 440 Yagi
Yeah, forgot to mention Scala. I use a lot of their antennas in non-amateur endeavors. --- Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Fred Seamans Sent: Friday, July 02, 2010 7:53 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: [Repeaters] Looking for HD 440 Yagi Jeff: Kathrein-Scala Antennas makes good heavy duty yagi and a log periodic antennas with radom and without. I have used them before. They will survive most mountain tops with ice and salt water sprays. They are expensive. Fred W5VAY From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Thursday, July 01, 2010 11:29 PM To: Repeater-Builder@yahoogroups.com; repeat...@yahoogroups.com Subject: RE: [Repeater-Builder] Re: [Repeaters] Looking for HD 440 Yagi I'll echo most of Dave's comments, and add a few... The MYA's tend to have finicky tuning, and I've never seen one sweep correctly out of the box. Close enough probably, but not optimized either. The BMOY's are broad band, with one model covering 406-440 MHz and another from 440-480 MHz. Maxrad stopped making the MYA antenna that I used a lot - MYA43012 - 12 elements, 430-450 MHz. Now you can only get the 12 element model in 450-470 range :-( I never had much problem tuning up the MYA yagis, but as Dave said, they usually weren't tuned well out of the box. Sealing up the connector is a PITA; I always removed the rear (reflector) element, removed/loosened the hardware to allow the feed to be slid to the rear of the boom, and then proceeded to put my jumper on it and seal it up right before sliding it back into position and tuning it. I'm now buying Sinclair SY307 series and Comprod 430-70 yagis (7 element, 10 dBd each, very close to being clones of each other) at about $140 each. Have about a dozen in service and more in stock for upcoming projects. My only complaint thus far is that they seem to not be consistant on what kind of connector is on the end of the pigtail - some came with N males, some with N females - picky picky. The Antennex gamma-fed UHF yagis are real dogs. The tuning is extremely touchy. Minor changes in placement of the jumper/feedline throw the tuning all over the place, and slight changes in distance from the mast and/or changing polarization will require retuning. The Sinclairs and Comprods are mostly immune to detuning in that regard, and always sweep well across the entire spec'ed range. I bought four of the 12-element models (two silver, two gold) when I found out I couldn't get the Maxrads any more, and they're still sitting in the warehouse, I wasn't happy with them after I tested them. I, too, had/have a lot of the old Larsen's in operation (5 and 8 element), but they don't make the ham splits any more. Although they aren't built as rugged as some of the others mentioned, they've held up pretty well. I just took down two of the 8-element models that had been up on a mountain for about 15 years and, aside from a couple of bent elements from falling ice, had held up pretty well. I replaced them becuase a) they were getting old and beat up, and b) I wanted to replace the feedline runs anyway so I figured I may as well swap out antennas at the same time, one less 200+ mile trip and tower climb to make in the future. I still have four of them at a site that have been up for just about 20 years now and they're still working. --- Jeff WN3A
Re: [Repeater-Builder] Erring on the Side of Caution....
That site has been around for along time, it used to be under another domain *www.ham.dmz.ro*, which now points to that new domain. On Thu, Jul 1, 2010 at 1:44 PM, La Rue Communications laruec...@gmail.comwrote: Ran across this website http://www.hampedia.net/motorola/mt-1000.php Found out it has the RSS to the Motorola MT1000. And me being the cautious guy to never get into legal crap with the big boys as I know how Motorola's Software License Agreement is big and scary.. Is this site legitimate or is this site just asking for trouble by posting RSS for the general public? Thoughts? Comments? Should I stay away from these people? Thanks! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
Re: [Repeater-Builder] Erring on the Side of Caution....
Yeah, thats what i assume since they have not been taken off, and they mainly have all the old dos stuff. But i am well aware of the motorola software licience agreement policy as well, since i work for a motorola dealer too. On Thu, Jul 1, 2010 at 2:12 PM, La Rue Communications laruec...@gmail.comwrote: So Motorola wont go ofter these people since they are based in another country? Glad to hear they have been around a while - just didnt want any legal crap with the Big Bat :-) John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - *From:* Jeff Ackerman kg6u...@gmail.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Thursday, July 01, 2010 2:05 PM *Subject:* Re: [Repeater-Builder] Erring on the Side of Caution That site has been around for along time, it used to be under another domain *www.ham.dmz.ro*, which now points to that new domain. On Thu, Jul 1, 2010 at 1:44 PM, La Rue Communications laruec...@gmail.com wrote: Ran across this website http://www.hampedia.net/motorola/mt-1000.php Found out it has the RSS to the Motorola MT1000. And me being the cautious guy to never get into legal crap with the big boys as I know how Motorola's Software License Agreement is big and scary.. Is this site legitimate or is this site just asking for trouble by posting RSS for the general public? Thoughts? Comments? Should I stay away from these people? Thanks! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
Re: [Repeater-Builder] Erring on the Side of Caution....
Well, RSS is very easy to find, as you found that web site, there are a few other websites that list RSS, although, those other sites are all in other countries, Russia, china and so forth. the newer windows versions, CPS, is harder to come by on the internet, its out there but not as publicly available, mainly distributed through private exchanges, and such. I have seen motorola take action on there windows software when it shows up on the internet, if you happen to find a listing for some CPS software on ebay, watch it for a few days and usually motorola finds it and tells ebay, then ebay cancles the auction automatically, iv herd several accounts of that, even if your a dealer and your listing new software it will be taken off ebay withen a day or so of listing it. I have seen aucitons of radios and the person will include a copy of the programming software, but in all accounts of those, they were older not supported radios, that used the RSS (dos) programming software, and iv not seen motorola report that kind of auction, i however havent looked for auctions for just RSS and see if it gets reported. From what i can make of it all, motorola seems to not be as strict with the older RSS as they are with the newer CPS. Jeff Ackerman - kg6uyz Peninsula Communications 6 Rossi Circle, Suite C Salinas, Ca 93907 j...@peninsulacom.com On Thu, Jul 1, 2010 at 2:38 PM, La Rue Communications laruec...@gmail.comwrote: Thanks Jeff! I am curious though - if the RSS is similar to Computer applications (I know the RSS *IS* software) but if its obsolete, a lot of software vendors don't mind if the obsolete software goes public / freeware. Even if it was made Open Source and people could configure it to work with any similar Motorola radio (If possible), would Motorola get upset about stuff like that happening with their licensed software? John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - *From:* Jeff Ackerman kg6u...@gmail.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Thursday, July 01, 2010 2:30 PM *Subject:* Re: [Repeater-Builder] Erring on the Side of Caution Yeah, thats what i assume since they have not been taken off, and they mainly have all the old dos stuff. But i am well aware of the motorola software licience agreement policy as well, since i work for a motorola dealer too. On Thu, Jul 1, 2010 at 2:12 PM, La Rue Communications laruec...@gmail.com wrote: So Motorola wont go ofter these people since they are based in another country? Glad to hear they have been around a while - just didnt want any legal crap with the Big Bat :-) John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - *From:* Jeff Ackerman kg6u...@gmail.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Thursday, July 01, 2010 2:05 PM *Subject:* Re: [Repeater-Builder] Erring on the Side of Caution That site has been around for along time, it used to be under another domain *www.ham.dmz.ro*, which now points to that new domain. On Thu, Jul 1, 2010 at 1:44 PM, La Rue Communications laruec...@gmail.com wrote: Ran across this website http://www.hampedia.net/motorola/mt-1000.php Found out it has the RSS to the Motorola MT1000. And me being the cautious guy to never get into legal crap with the big boys as I know how Motorola's Software License Agreement is big and scary.. Is this site legitimate or is this site just asking for trouble by posting RSS for the general public? Thoughts? Comments? Should I stay away from these people? Thanks! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
Re: [Repeater-Builder] Erring on the Side of Caution....
One other thing is hams already modify there RSS to suite there needs, mainly speaking of the 900 mhz rss for GTX's, MTX9000's and so forth. But alot of these hams that have this modified software are very reluctant to let it go wild out on the net for fear of the big M cracking the whip, therefor its all kept in a tight group, but in some cases its not. On Thu, Jul 1, 2010 at 2:55 PM, Kris Kirby k...@catonic.us wrote: On Thu, 1 Jul 2010, La Rue Communications wrote: Thanks Jeff! I am curious though - if the RSS is similar to Computer applications (I know the RSS *IS* software) but if its obsolete, a lot of software vendors don't mind if the obsolete software goes public / freeware. Even if it was made Open Source and people could configure it to work with any similar Motorola radio (If possible), would Motorola get upset about stuff like that happening with their licensed software? Motorola will sue you into bankruptcy if you cross them. However, they have larger problems. Remember that they are selling radios that cost $1500+ to every agency under the sun because of the narrow-banding that is coming up in a few years. The secondary markets of the existing wideband radios will be legal Part 90 users who do not want to pay for the new radios, and can afford the filter and frequency standard replacement as well as the tech's time on the bench to make sure the radio is within spec. On top of those factors, many of the radios weren't made to deal with the splinter frequencies which will be used in increasing numbers in the future. I suppose if one was bright and wanted to hedge a few bets, one could buy up a large number of Maxtracs, have them sent to China, install new timebases and filters, check them there cheaply, then send them back to the US and have them checked again, programmed, and sold to the other Part 90 users. Or one could have 900MHz Maxtracs turned into 450MHz Maxtracs, keep the 2.5KHz deviation, and use HearClear. That would be fundamentally changing the operation of the radio and might involve learning 68HC11 microprocessors and reverse engineering the radio. But those costs are cheaper in China, where the choice is do I want to eat today? versus Do I want to eat next week? or I still have four months before they foreclose. Of course, the growing dependence on CODECs to achieve bandwidth savings in digital radio sets an artificial obsolescence point in the lifetime of the radio. As long as the FCC and industry keeps thinking they can squeeze blood from a turnip, two-way radio will see smaller allocations and the Big Five telecom players will enjoy allocations in the multi-megahertz. But Motorola plays in that market too. -- Kris Kirby, KE4AHR Disinformation Analyst -- Jeff Ackerman Peninsula Communications 6 Rossi Circle, Suite C Salinas, Ca 93907 j...@peninsulacom.com
RE: [Repeater-Builder] Re: [Repeaters] Looking for HD 440 Yagi
I'll echo most of Dave's comments, and add a few... The MYA's tend to have finicky tuning, and I've never seen one sweep correctly out of the box. Close enough probably, but not optimized either. The BMOY's are broad band, with one model covering 406-440 MHz and another from 440-480 MHz. Maxrad stopped making the MYA antenna that I used a lot - MYA43012 - 12 elements, 430-450 MHz. Now you can only get the 12 element model in 450-470 range :-( I never had much problem tuning up the MYA yagis, but as Dave said, they usually weren't tuned well out of the box. Sealing up the connector is a PITA; I always removed the rear (reflector) element, removed/loosened the hardware to allow the feed to be slid to the rear of the boom, and then proceeded to put my jumper on it and seal it up right before sliding it back into position and tuning it. I'm now buying Sinclair SY307 series and Comprod 430-70 yagis (7 element, 10 dBd each, very close to being clones of each other) at about $140 each. Have about a dozen in service and more in stock for upcoming projects. My only complaint thus far is that they seem to not be consistant on what kind of connector is on the end of the pigtail - some came with N males, some with N females - picky picky. The Antennex gamma-fed UHF yagis are real dogs. The tuning is extremely touchy. Minor changes in placement of the jumper/feedline throw the tuning all over the place, and slight changes in distance from the mast and/or changing polarization will require retuning. The Sinclairs and Comprods are mostly immune to detuning in that regard, and always sweep well across the entire spec'ed range. I bought four of the 12-element models (two silver, two gold) when I found out I couldn't get the Maxrads any more, and they're still sitting in the warehouse, I wasn't happy with them after I tested them. I, too, had/have a lot of the old Larsen's in operation (5 and 8 element), but they don't make the ham splits any more. Although they aren't built as rugged as some of the others mentioned, they've held up pretty well. I just took down two of the 8-element models that had been up on a mountain for about 15 years and, aside from a couple of bent elements from falling ice, had held up pretty well. I replaced them becuase a) they were getting old and beat up, and b) I wanted to replace the feedline runs anyway so I figured I may as well swap out antennas at the same time, one less 200+ mile trip and tower climb to make in the future. I still have four of them at a site that have been up for just about 20 years now and they're still working. --- Jeff WN3A
RE: [Repeater-Builder] Quantar Simulcast Issue
To get the RF phase accuracy you're implying that is required would mean that everything in the RF path would have to guarantee that phase relationship. That means the same length RF interconnect cables inside the cabinet, same RF feedline length (or full-wavelength multiples thereof), same antenna type, etc. Even if you could guarantee that kind of accuracy at the time of installation, thermal effects would quickly throw it way off (cables expanding/contracting with temperature for example). Not to mention the propagation delay will vary a whole lot with temperature, humidity, etc. Just not gotta happen --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of DCFluX Sent: Thursday, June 24, 2010 12:51 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Quantar Simulcast Issue Well if the transmitters are running at the same frequency but at a different phase it is reasonable to expect that there would be some point where the 2 transmitters are at close to the same power level, but 180 degrees out of phase which should cancel out the receiver or at least make interesting noises. Well, yeah, I know what propagation delay is, but I don't see where the phase of the reference has an effect on anything. Are you thinking that the transmitter's RF carrier needs to be launched with phase coherence at each site? --- Jeff WN3A Yahoo! Groups Links
[Repeater-Builder] I've been lookin' for line in all the wrong places...
Anyone have, or know of, a surplus of 1/2 line? I've been scouring the surplus places, eBay, etc., but haven't found any decent deals. I can use pieces or reels anywhere from a few hundred to a few thousand feet. RFS, Andrew, et. al., anything but Commscope. Thanks in advance. --- Jeff WN3A
RE: [Repeater-Builder] Simulcast Information on-line
Yes, but you'll probably find them most often in Micor PURC (paging) stations. Components of interest include the high-stability and ultra-high-stability oscillators, simulcast control card, audio delay unit (usually made by Allen Avionics), etc. By no means a state-of-the-art system, but they worked...more or less...at least for paging. --- Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of TGundo 2003 Sent: Thursday, June 24, 2010 6:13 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Simulcast Information on-line Were there specific UHF MICOR components that suited themselves to Simulcasting? Tom W9SRV --- On Thu, 6/24/10, Kevin Custer kug...@kuggie.com wrote: From: Kevin Custer kug...@kuggie.com Subject: Re: [Repeater-Builder] Simulcast Information on-line To: Repeater-Builder@yahoogroups.com Date: Thursday, June 24, 2010, 3:50 PM skipp025 wrote: For those of you who'd like to see a few different examples of various Simulcast Systems explained. http://www.simulcastsolutions.com/case-studies.htm http://www.simulcastsolutions.com/case-studies.htm Another explanation is available here: http://www.repeater-builder.com/k7pp/index.html http://www.repeater-builder.com/k7pp/index.html Kevin Custer Yahoo! Groups Links (Yahoo! ID required)
[Repeater-Builder] Tessco - free shipping promotion
My Tessco account rep emailed me that they're running a promotion this week - free shipping. So if you're thinking about buying a big repeater antenna or a reel of Heliax, save big money on truck freight if you order this week. --- Jeff WN3A
RE: [Repeater-Builder] Quantar Simulcast Issue
Are the cables coming from the GPS reference are the same length at both sites? Maybe I'm missing something here, but how the heck would the length of the cable from the reference oscillator to the transmitter/exciter matter? It's just the frequency reference (10 MHz or whatever) for the synthesizer; it has no effect on delay, phase, amplitude response, or anything else related to the modulated audio. Also if these are VHF it could be that the reference frequency (channel spacing) is 5 kHz, if that is the case a harmonic of a paging tone might get past the audio pass band filtering 300 - 3000 Hz typically and is fooling the PLL divider. This seems like a longshot. I think Bill's original guess is most likely on the right track - a DC offset problem. I'm assuming the transmitters are being modulated through a non-DC-coupled input to the modulator? Maybe look for a coupling cap with high leakage. Another thought is asymmetrical clipping of the audio. --- Jeff WN3A
RE: [Repeater-Builder] Quantar Simulcast Issue
Propagation delay in the coax. Propagation delay doesn't affect anything on the reference output side of the GPSDO. The phase of the reference oscillator can vary -- the synthesizer doesn't care about the phase of the reference oscillator, only the frequency. Likewise, the VCO output isn't synchronized in any way to the reference oscillator as far as phase goes. Get a dual trace oscilloscope and feed it with a 10 MHz GPS, off of a Tee and into 2 different lengths of coax. Well, yeah, I know what propagation delay is, but I don't see where the phase of the reference has an effect on anything. Are you thinking that the transmitter's RF carrier needs to be launched with phase coherence at each site? --- Jeff WN3A
RE: [Repeater-Builder] Astron RS50 Power Supply
Everyone is entitled to make an ass out of himself now and then, but you're abusing the privilege... -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of kevin valentino Sent: Sunday, June 20, 2010 9:21 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Astron RS50 Power Supply Hey you still owe me 3 # bucks for sending you a Uniden key! Hope the whole world knows know! you just blew me off?!!! it was over a year ago at least! sent you several emails. guess if you can't afford a couple bucks then you should not to try to make yourself out to mister want to be!Which for a couple bucks is nothing!!!Guess you can't be trusted! Mr. Mike Morris! Wa6ilg, so impressed, no code! wannabie!!! yes you are!!! --- On Sun, 6/20/10, Mike Morris wa6...@gmail.com wrote: From: Mike Morris wa6...@gmail.com Subject: Re: [Repeater-Builder] Astron RS50 Power Supply To: Repeater-Builder@yahoogroups.com Date: Sunday, June 20, 2010, 6:23 PM At 11:22 AM 06/20/10, you wrote: Hi Guys, I am trying to download a schematic on this site for the RS50M Power Supply and keep getting a 404 Error on each attempt on all the supplies. Any ideas? Did you use the email link on the 404 page to tell the guys at repeater-builder? I just checked the RS50 links and they all seem to work... Let me know which link doesn't work and I'll fix it. You might want to read the repair and modification notes on the Introductory Information page. At the least you should add the missing compensation cap and the missing lock washers. Make sure the negative side of the supply is NOT connected to the case. Eric WB6FLY posted a informative note about that a while back. It's reproduced on the Introductory Information page. According to the schematic the main diodes in the RS-50 is the 1N1184A. International Rectifier calls it a 40 amp diode. What brand is in your unit? I rebuilt an RS50 a couple of years ago and used a pair of the 1N2129A (60 amp diode). If I were to do it over again I'd use a 100a diode like the 1N3288 that I use in the RS-70. Mike WA6ILQ
RE: [Repeater-Builder] Astron RS50 Power Supply
Also our above mentioned power supply which operates our 2 Meter and 440 Repeaters and a low power link started humming yesterday. A trip to the tower showed that the two large wires coming from the Pass Transistors to the post on top of the regulator board and into the 1000 Uf Electrolytic got so hot it melted the insulation an inch back on the wires, burned an area the size of a quarter on the fiter side of the regulator board, turned the terminal black on the Cap. and cracked the plastic on the cap. It never blew the fuse and a check of the voltage showed it regulating under load and hardly a trace of AC on the 13 volt output. The MOV or eight amp AC fuse never blew. All the equipment hooked to the supply took off and worked well on another supply. Anyone have a guess as to what caused this obvious surge ontop of the cap? I am going to replace the Cap. and one resistor on the regular board which is discolored and hope for the best. Any advise appreciated. Thanks in advance JIM KA2AJH Wellsville, N.Y. I've seen this happen a number of times to RM-50's and RS-50's, most recently to an RS-50M that's one of my bench supplies. That connection (where the high-current wires connect to the top of the filter cap with the PC board sandwiched inbetween) leaves something to be desired. Eventually it becomes a point of high resistance, either due to the screws/lockwasher no longer being tight due to vibration or through thermal cycling, or the copper foil oxidizes a bit, or similar causes. Once the resistance goes up even a little, the heat caused by I2R at that point only worsens the problem, and ultimately it becomes a thermal runaway kind of a situation, yielding the results that you saw. Bottom line - there probably wasn't any surge that set this off, it was a function of design and age. --- Jeff WN3A
RE: [Repeater-Builder] Micor COS issues.... continuing
I always use an NPN transistor (2N4401 or whatever floats your boat) as an inverter on the Micor COR, with a voltage divider on the base. Micor COR to base through 10K, 4.7K from base to emitter, ground emitter, collector becomes active-high COR. Pull up collector with 12V through 1K (or whatever) if your controller doesn't have a pull-up internally. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Josh Sent: Monday, June 21, 2010 11:58 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor COS issues continuing I've been fighting this issue for a while now. I've tried some bandaids to deal with it, tried multiple repeater controllers (including one I designed myself with an ATMEGA328 Microcontroller (I'll probably be releasing this design as open source coming up)... and I'm fighting the same problem everywhere... My micor COS signal is weird. When the squelch is closed, I get right around 8 volts, taken from pin 8 of the modified mobile audio/squelch board - the tried and true process just about everybody uses. When the squelch opens, I'm at not ground potential, but right about half a volt. This isnt really the sort of logic signal I want (I want this thing to be dead nuts zero, not half a volt). What is the deal here? I've tried adding resistors in series to fudge things and cause voltage drop, but thats not really even working that well. I've tried the 2n circuit, but that doesnt really have a lot to do with this (although a variation of that might come into play I suspect) How do I best solve this so I can get my repeater on the air?? This is very close to the last issue I have remaining to solve. Help / advice is greatly appreciated. Josh
RE: [Repeater-Builder] Micor COS issues.... continuing
Here's how we've designed our controllers' COR, CTCSS, and logic inputs for many years: Feed the COR signal to the top of a voltage divider. The upper resistor is 10K and the lower is 4.7K. Feed the junction of the divider to the base of an NPN such as a 2N3904, 2N, etc. You'll have a 3:1 voltage divider that in essence multiplies the transistor's base-emitter drop by three, so the input threshold will be ~2V instead of ~0.7V. And, you'll have 10K and an NPN to buffer the outside world from whatever logic IC you're using for your input port. Seems that sick minds think alike, Bob :-)
RE: [Repeater-Builder] Re: Alinco DR-03T
Have a 110 watt Mastr II station on 33 MHz that would be a nice 10 repeater (or remote base for that matter), with power supply and cabinet, $200, pick up only (Philly). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of K4SLB Steve Butler Sent: Monday, June 14, 2010 1:55 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Alinco DR-03T I would love one. contact me off forum K4SLB at R2I.NET From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of terry_wx3m Sent: Monday, June 14, 2010 08:51 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Alinco DR-03T I have some Micor mobiles on 31 MHZ 100 Watt would make dandy 10 meter radios. Yours free for the shipping, --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Doug Hutchison specialq@... wrote: Hi Andrew, Initially thank you for announcing the new box - cannot find it here yet. Have a DR-M03 obsolete (no T). It is OK as a link TXR, duty cycle might be a problem for repeater but a big enough cooler may solve that. Mine is 10w o/p, performs OK. Doug On 13/06/2010 20:30:33, vk4jv (vk...@...) wrote: Hi Guys Has anyone used the new alinco DR-03T 10M rigs in a repeater ? I wish to get a 10M repeater going but have to use split sites and use UHF links between them... also.. any other ideas on radios to use ? cheers Andrew Yahoo! Groups Links
RE: [Repeater-Builder] MOVs for power supply primary
OK, you're looking for something in the middle then. For parallel protectors, LEA CFS or SP series, or Transtector Apex II, may be more in the price range you're looking for (under $1000). Since I don't use protectors of that kind regularly, I don't have any other recommendations other than to stick with repetuable manufacturers and read the data sheets. The cheaper ones will probably be MOV-only. Others may use a combination of MOV's, SAD's, and/or gas discharge tubes. There are pros and cons to each... I don't know of any series protectors that fall into the price range of what I would think you're looking for. Someone else (Eric?) mentioned Square D. The only Square D ones I've used are the ones that are built into the panel (Surgelogic or something like that?), not the add-on ones. We had to replace one in a 3-phase 480/277 panel not too long ago, that's the only reason I'm familiar with them (they have an audible alarm that goes off when the arrestor detects a fault, a nice feature). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Wednesday, June 09, 2010 8:51 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] MOVs for power supply primary OK, I'm familiar with those single-point grounding panel protection devices. How about a service panel protector for home use? And a service panel protector for a small (200A) 3-phase panel? I ask, rather than simply Google for it, because Google could come up with some units that are not good. Chuck WB2EDV
RE: [Repeater-Builder] MOVs for power supply primary
Hmmm. That's a tougher one. Mostly I use the Polyphasers (PLDO-120US-15A or -20A) at sites that don't have facility-wide protection. The TrippLite Isobar Ultra series is another (ISOBAR8ULTRA et al). The Isobars also have a $50,000 equipment warranty (can't say I've ever had to use it, don't know how much red tape there is to go through). I like the Polyphasers because it's designed to mount to a ground panel/bus bar, so I mount it to the bus bar that has all of my other arrestors (coax, telco, etc.) on it to provide a common-point ground. The Isobar doesn't have provisions for direct grounding - it relies only on the equipment grounding conductor in the AC cord, but the TrippLite has arguably better EMI/RFI filtering than the Polyphaser. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Tuesday, June 08, 2010 4:48 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] MOVs for power supply primary OK, I should have been more specific. What would be a reasonable unit for a repeater site that may have only a couple thousand dollars worth of equipment inside? Chuck WB2EDV - Original Message - From: Jeff DePolo j...@broadsci.com mailto:jd0%40broadsci.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Tuesday, June 08, 2010 4:22 PM Subject: RE: [Repeater-Builder] MOVs for power supply primary Probably the ones I've had the most luck with are the Islatrol series from Control Concepts. I think they have been bought out by Emerson or Liebert or one of the other companies that have power divisions. Anyway, they call these active tracking filters. They not only are TVSS's but also filter noise, low-amplitude spikes, etc. Right now I'm typing from a mountaintop site (broadcast) that we re-built a few years ago. We put in an Islator I-2100 (120/240V single-phase). The old equipment shelter which had been here since 1990 had the same model unit. In the 15+ years we've been managing and maintaining the site, we've had zero surge-related failures, and this site sticks out like a sore thumb as far as lightning goes. In the last few years I've used the same series of arrestors for new site builds at a dozen sites or so and have had no power-related problems. Others that make comparable-quality products include Joslyn, Transtector, and Innovative Technologies. There is one big difference (to me anyway) between TVSS's, that being whether they are the series or parallel type. Series type takes the utility service (or transfer switch output if there's a generator too) as its input, and provides a protected output to feed the panel(s). Parallel type is typically connected to a breaker in the panel, which puts it in parallel with all of the loads. I much prefer series. Parallel type can be less effective because a) there will always be some inductance and resistance in the wiring between the panel and the protector, b) if the TVSS conducts, there's a good chance it will trip the breaker in the panel, resulting in no protection until the breaker is reset, and c) they are much less effective as a noise filter. The upside to parallel type is they can easily be added at any time just by popping breakers in the panel and feeding the arrestor. Series, on the other hand, are in-line with the service conductors, so if you want to add one (or repair one), you have to take the service down. Series tends to also be more expensive, especially for three-phase and unlike parallel type, the price goes up as the current rating goes up for obvious reasons. A good 200A single-phase arrestor of the ilk I'm talking about starts at about $1000 and goes up quite a ways from there. I think these single-phase I-2100's were in the $2000 range. I recently spec'ed a 120/208 3-phase Transtector (parallel type) for another site where I'm much less concerned about power-wise, and that was about $1800. No cheap, but where you're protecting equipment in the 6 and 7 figure range, it's a no-brainer. If you're repeater is a Micor mobile and an Astron, it might be hard to justify... :-) --- Jeff
RE: [Repeater-Builder] MOVs for power supply primary
Probably the ones I've had the most luck with are the Islatrol series from Control Concepts. I think they have been bought out by Emerson or Liebert or one of the other companies that have power divisions. Anyway, they call these active tracking filters. They not only are TVSS's but also filter noise, low-amplitude spikes, etc. Right now I'm typing from a mountaintop site (broadcast) that we re-built a few years ago. We put in an Islator I-2100 (120/240V single-phase). The old equipment shelter which had been here since 1990 had the same model unit. In the 15+ years we've been managing and maintaining the site, we've had zero surge-related failures, and this site sticks out like a sore thumb as far as lightning goes. In the last few years I've used the same series of arrestors for new site builds at a dozen sites or so and have had no power-related problems. Others that make comparable-quality products include Joslyn, Transtector, and Innovative Technologies. There is one big difference (to me anyway) between TVSS's, that being whether they are the series or parallel type. Series type takes the utility service (or transfer switch output if there's a generator too) as its input, and provides a protected output to feed the panel(s). Parallel type is typically connected to a breaker in the panel, which puts it in parallel with all of the loads. I much prefer series. Parallel type can be less effective because a) there will always be some inductance and resistance in the wiring between the panel and the protector, b) if the TVSS conducts, there's a good chance it will trip the breaker in the panel, resulting in no protection until the breaker is reset, and c) they are much less effective as a noise filter. The upside to parallel type is they can easily be added at any time just by popping breakers in the panel and feeding the arrestor. Series, on the other hand, are in-line with the service conductors, so if you want to add one (or repair one), you have to take the service down. Series tends to also be more expensive, especially for three-phase and unlike parallel type, the price goes up as the current rating goes up for obvious reasons. A good 200A single-phase arrestor of the ilk I'm talking about starts at about $1000 and goes up quite a ways from there. I think these single-phase I-2100's were in the $2000 range. I recently spec'ed a 120/208 3-phase Transtector (parallel type) for another site where I'm much less concerned about power-wise, and that was about $1800. No cheap, but where you're protecting equipment in the 6 and 7 figure range, it's a no-brainer. If you're repeater is a Micor mobile and an Astron, it might be hard to justify... :-) --- Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Tuesday, June 08, 2010 11:34 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] MOVs for power supply primary Jeff - Could you suggest some makes and models and maybe explain why they are superior to others? Chuck WB2EDV - Original Message - Good surge arrestors/TVSS's are expensive, and like most things in life, you get what you pay for. If your site has a good surge arrestor at the service entrance, you really shouldn't need anything extra. --- Jeff WN3A
RE: [Repeater-Builder] Re: Milcom International UHF PA
If I want the caps changed, is there anyone in particular at Crescend I need to talk to? I wasn't aware that they would support the Milcom line. No, just fill out the RMA form from their web site. You might want to ask for an estimate or quote before you send the unit in, but they'll want the RMA form first. --- Jeff WN3A
RE: [Repeater-Builder] Micor Repeater Question
I have a friend running a 75W Micor UHF repeater and he needs to operate it for a single user who uses regular PL tone. My friend has a PL module installed on the Tone Squelch board in I presume you mean audio-squelch board. Does he need a single PL tone encoder card for the card cage? 146.2 Hz. is the tone he needs. The PL encoder plugs into the exciter, not the card cage. One jumper cut on the exciter board is required. After he installs such a card, would the repeater transmit the 146.2 PL tone, even if activated by the Tone Remote? Yes. Third question - Are there any other cards or PL modules out there besides the Card Cage type, or are they all strictly the ones that fit in the Unified Chassis? See above. Don't confuse a PL encoder board with an F1-PL card in the cage, totally different animal... --- Jeff WN3A
RE: [Repeater-Builder] MOVs for power supply primary
Hello to group, Is putting a MOV from hot to ground, neutral to ground, on the primary of the transformer of the power supply a good idea.. I have a ICE surge suppressor on in front as well but thought I would put more inside the supply for back up. I'm not that big of a fan of MOV's, but if you really feel the need to add them across the transformer primary, as long the input to the power supply is properly fused, whatever floats your boat. Also, are the MOVs that radio shack sell any good. Rated at 130VAC. Any body used them... I'm not sure that there's anything that Radio Shack sells any more that's any good, is there? Seriously, I'd buy Last question: when MOVs fail or take a surge do they fail in a shorted condition taking out the fuse till the MOV can be replaced, or do they blow or fail open leaving the supply working. My experience that small MOV's fail in one of two ways. Either they fail shorted, quite often with no outward visible signs, or they fail open catastrophically as a zillion pieces of shrapnel that can cause damage to nearby components, wiring, people, livestock, etc.. Another downside to MOV's is that after they've successfully quenched an over-voltage event of any significant energy, their clamping voltage changes. So, you may end up with less and less protection over time. Good surge arrestors/TVSS's are expensive, and like most things in life, you get what you pay for. If your site has a good surge arrestor at the service entrance, you really shouldn't need anything extra. --- Jeff WN3A
RE: [Repeater-Builder] Re: Milcom International UHF PA
28-29 amps is on the high side. Are you using the amp at more than maybe 5 MHz or so from the original frequency? Some of the Milcom/Crescend amps are tunable, but many used fixed-value metal-clad mica capacitors in the base and collector matching. The values of the caps and/or their placement along the microstrips is varied depending on frequency. While you could experimentally determine the right values/placements using common sense techniques, it's probably easier just to send it to Crescend to have them move it to your frequency. I have a 350 watt Vocom UHF amp that had the same issue - fixed caps. After counting how many caps I'd have to futz with, I concluded it was cheaper to send it to them and letthem do it for $200. They turned it around in about a week. If you need 250 mW in and 100 watts out, a Mastr II PA would do you nicely (and cheaply!). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Adam Feuer Sent: Saturday, June 05, 2010 11:35 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Milcom International UHF PA Hi Alex, Thanks for the reply! Your description of the pots was great but I don't see ANY tuning caps on any boards in this amp. There's a 10watt board that feeds a 65w board. Then, this 65w board gets split to feed two more 65w boards which get combined as the final output. I can easily set R10 to 100 watts but I would like more info on the tuning caps if it's applicable to this amp. At 100 watts the amp is drawing about 28 to 29 amps. I may be incorrect but I thought some of my other 250mw in 100w out PA's only draw 22 amps. Thanks again! Adam N2ACF On 6/5/2010 6:04 PM, opelgtalex wrote: Adam- R10 controls the bias voltage to the first stage driver- this sets the power out of the amp. Turn this pot down (lower the PA output) peak out all tuning caps starting at the 1st stage, then the 2nd and on to the 4 driver boards. Once all tuning caps are adjusted for peak output, then adjust R10 for the amplifiers rated power out (100W in your case). R9 controls the foldback power in case of a high temp condition the power output is cut by 3dB- the thermal switch is located just below the control board. As per manual R9 is adjusted by removing power from the cooling fan, key the RF source, wait for the unit to reach 135deg F and adjust R9 for 3dB below rated amp output- this is per manual. Hope this helps, Alex --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Adam Feuerfeu...@... wrote: Hello All, I have a Milcom International UHF PA on the bench. Model number is P12-O5HA1-C1 rated at 250mw in with 100w out. I'm trying to identify what two pots (R9 R10) do on a board that seems like a control board. Both pots appear to vary the output power and current draw, although one does it more dramatically than the other. Anyone have a manual or information for this PA? Any help would be greatly appreciated. Thanks!! Adam N2ACF Yahoo! Groups Links
RE: [Repeater-Builder] Re: Which Micor RX for Two Meters
Start with the basics: 1. Clean all of the contact pins and female contacts with a good contact cleaner like Deox-It. When re-installing each of the boards/cards, check check to make sure that all of the male pins are straight and that none of the female contacts have spread - tighten up by squeezing gently with needle-nose pliers where necessary. 2. Clean (or replace) the IDC pot if you haven't already. If speaker audio is normal and doesn't vary in level, and/or if PL injection doesn't change when the audio level changes, chances are it's somewhere in the repeat audio path. But if speaker audio level changes too, then clean/replace the audio level pot on the audio/squelch board as well. Those are my first-pass suggestions. If you want to provide more detail on the problem, including what cards you are using and how you have Tx and Rx wired from the controller to the station, I can probably offer some other suggestions. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Lee Pennington Sent: Sunday, June 06, 2010 10:42 AM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Which Micor RX for Two Meters No, I did every thing from the RB station to repeater conversion instructions. My problems with the Xmitter involve fluctuating audio deviation levels. It is frequency stable and I have a solid 75-78 watts out of the cans. Thanks for your concern and keep up the good work. de Lee K4LJP 73 On Sun, Jun 6, 2010 at 9:57 AM, Scott Zimmerman n3...@repeater-builder.com mailto:n3...@repeater-builder.com wrote: Did I do the transmitter as well? (I don't remember. I do so many projects.) Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 Lee Pennington wrote: Exactly right, Scott did the coils and castings on mine five years ago.Hasn't been touched since.now the xmitter, well that's another story. On Sun, Jun 6, 2010 at 8:36 AM, terry_wx3m wx3m.te...@gmail.com mailto:wx3m.terry%40gmail.com mailto:wx3m.te...@gmail.com mailto:wx3m.terry%40gmail.com wrote: Do yourself a favor and send the receiver and $100 to Scott n3...@repeater-builder.com mailto:n3xcc%40repeater-builder.com mailto:n3xcc%40repeater-builder.com mailto:n3xcc%2540repeater-builder.com . Then you will have a receiver that is in the 131-150 range. It is worth EVERY penny. It will exceed book specs. --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%2540yahoogroups.com , Tim - WD6AWP tisaw...@... wrote: I have the following Micor receivers. TLD4071B, TLD5781AV, and TLD8271B3. Unfortunately none are in range 2. Which, if any of these would be the best for a receiver on 144.5 Tim WD6AWP -- Always drink upstream from the herd. -- Always drink upstream from the herd.
RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer
Mine don't have labels on them. Usually they were sold as part of an SP package that included the window filters, multicoupler, etc. I haven't tuned or swept this particular set, but from experience, the cavity resonance will tune over a wide swath, probably the full 406-512 MHz, but the loop lengths may not be optimal over such a wide span (depending on how the cavities are being used), and likewise, the cable lengths will vary. You have something in particular in mind you want me to test? --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Sunday, May 30, 2010 12:29 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer Jeff, Can you positively identify the window filters by part number? Also, what is the useful frequency range of the units you purchased? 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Jeff DePolo Sent: Sunday, May 30, 2010 8:39 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer snip I bought two sets of those window filters from the same guy, but I knew what they were, caveat emptor is the golden rule at Dayton or any other hamfest. Actually I think I gave him $75 for the pair, and I took the two cleanest/newest ones he had (the newer dark-tan ones). --- Jeff WN3A snip
RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer
Yes, they did sell window filter as a separate catalog item, but if they were sold as such they would have had a factory sticker on it. The ones I have don't have a sticker, which is why I said they were probably part of a package that would likely have had an SP part number rather than a DB. These cavities are very tightly coupled, typically about 0.3 dB or so insertion loss per cavity. Strung together, the total insertion loss is about 1.5 dB. Because of the coupling, each cavity individually doesn't have a very high Q, so if you were to take one of these units and split it to try to make a duplexer out of it, you'd probably only get about 40 dB or so of isolation at 5 MHz offset. Even if you did want to try it, you'd have to change cable lengths to get the pass response of each cavity to add on-frequency rather than creating a wide window filter passband as they were originally cabled. They do tune fine down to 440 as-is (i.e. as a window filter). --- Jeff -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Monday, May 31, 2010 12:52 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer Not really. I had not seen this in any of my older catalogs, and I wondered if in fact the unit was made by Decibel Products. Like many RF products, ferrite isolators in particular, the frequency range stated in a manufacturer's catalog refers to the capability to construct- which is not the same as the field-tunable range of a specific product. I was curious if the window filter (AKA preselector) could be useful in the 70 cm Amateur band without modifying the coupling loops or jumper cables. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Jeff DePolo Sent: Monday, May 31, 2010 6:09 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer Mine don't have labels on them. Usually they were sold as part of an SP package that included the window filters, multicoupler, etc. I haven't tuned or swept this particular set, but from experience, the cavity resonance will tune over a wide swath, probably the full 406-512 MHz, but the loop lengths may not be optimal over such a wide span (depending on how the cavities are being used), and likewise, the cable lengths will vary. You have something in particular in mind you want me to test? --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Eric Lemmon Sent: Sunday, May 30, 2010 12:29 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer Jeff, Can you positively identify the window filters by part number? Also, what is the useful frequency range of the units you purchased? 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Jeff DePolo Sent: Sunday, May 30, 2010 8:39 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer snip I bought two sets of those window filters from the same guy, but I knew what they were, caveat emptor is the golden rule at Dayton or any other hamfest. Actually I think I gave him $75 for the pair, and I took the two cleanest/newest ones he had (the newer dark-tan ones). --- Jeff WN3A snip
RE: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer
Sorry to hear you got the proverbial shaft. But all's not lost. If you need a duplexer, I'll trade you a Motorola T1504 (pass/reject) duplexer in good shape that I had on my table at Dayton that didn't sell. I was asking $125 for it. I'll trade you straight across if you pick up shipping in both directions, and I'll even tune it on the VNA and send you the plots. I bought two sets of those window filters from the same guy, but I knew what they were, caveat emptor is the golden rule at Dayton or any other hamfest. Actually I think I gave him $75 for the pair, and I took the two cleanest/newest ones he had (the newer dark-tan ones). --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Josh Sent: Saturday, May 29, 2010 9:27 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Help Needed (Guidance and advice) tuning a DB Products Duplexer Certainly not what I was expecting... Yeah, I bought one from 'that guy'. It's more than an untrained eye - he straight lied to me... said 'under these caps are where you'll tune the capacitors' - I should have popped one off and looked down the hole. Maybe he was clued in, maybe he wasnt - either way, that's what I bought. Dangit :P So if all I have are pass cavities what 'are' they good for ? Guess I've got to find another dupelxer. j --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Jeff DePolo j...@... wrote: Ok so here's what I've got (I think) http://www.n2ckh.com/FORSALE/REPEATERS/DUPLEXERS/DB4076/DSC02678.JPG Hamvention special, 4 cavities, appears to be a DB Products 4076 family unit. My bench tools: HP 8924c w/ Spec Analyzer and Tracking Generator. There was a guy at the Hamvention that had several sets of Decibel four-cavity window filters, selling for $50 each, which, to the untrained eye, would look like an older DB4076. As you said, there would be nothing in the hole where the capacitor would be in a regular DB4076. In essecence, what you have are just plain-jane pass cavities. As a second means of confirming that you do, in fact, have a window filter, is there an antenna tee, or are the four cavities cabled together in cascade? If the latter, then you probably have a window filter. And as a third means of confirming, is there is a label on the front? If not, was there any signs of a label having once been there? If not, then that's yet one more indication that it isn't a DB4076. Decibel made two varieties of pass cavities used in window filters in that era. One had adjustable loops (less common), the other had fixed loops. If your loop connectors have a rectangular chrome plate around them with insertion loss calibration marks, you have the less-common adjustable ones. If you just see four philips-head screws and no chromed plate around the connectors, then yours is not adjustable. If you have the adjustable type, you could probably use them as a pass-only duplexer, but with mediocre isolation, even with the insertion loss cranked up higher than you'd like. If you have the non-adjustable ones, they have very tight coupling, so you're not going to get the isolation you'd need for a repeater. Did I buy a piece of junkola? Teach me obie-wan. Not junk, but maybe not what you were expecting... --- Jeff WN3A
RE: [Repeater-Builder] Help Needed (Guidance and advice) tuning a DB Products Duplexer
Ok so here's what I've got (I think) http://www.n2ckh.com/FORSALE/REPEATERS/DUPLEXERS/DB4076/DSC02678.JPG Hamvention special, 4 cavities, appears to be a DB Products 4076 family unit. My bench tools: HP 8924c w/ Spec Analyzer and Tracking Generator. There was a guy at the Hamvention that had several sets of Decibel four-cavity window filters, selling for $50 each, which, to the untrained eye, would look like an older DB4076. As you said, there would be nothing in the hole where the capacitor would be in a regular DB4076. In essecence, what you have are just plain-jane pass cavities. As a second means of confirming that you do, in fact, have a window filter, is there an antenna tee, or are the four cavities cabled together in cascade? If the latter, then you probably have a window filter. And as a third means of confirming, is there is a label on the front? If not, was there any signs of a label having once been there? If not, then that's yet one more indication that it isn't a DB4076. Decibel made two varieties of pass cavities used in window filters in that era. One had adjustable loops (less common), the other had fixed loops. If your loop connectors have a rectangular chrome plate around them with insertion loss calibration marks, you have the less-common adjustable ones. If you just see four philips-head screws and no chromed plate around the connectors, then yours is not adjustable. If you have the adjustable type, you could probably use them as a pass-only duplexer, but with mediocre isolation, even with the insertion loss cranked up higher than you'd like. If you have the non-adjustable ones, they have very tight coupling, so you're not going to get the isolation you'd need for a repeater. Did I buy a piece of junkola? Teach me obie-wan. Not junk, but maybe not what you were expecting... --- Jeff WN3A
Re: [Repeater-Builder] Fwd: DB4379UHF combiner
If you wanted to go with 2 2ch combiners instead of 1, you can put 451.525 and 453.525 on one and 451.550 and 453.550 on another if your worried about desence and such. But you would want to get a hybrid coupler, 2 inputs, 1 output and 1 port for dummyload. On Thu, May 27, 2010 at 11:32 AM, Ted Leonard n2...@verizon.net wrote: To the group, I received the attached e-mail from a friend in the two way business. Does anyone know if his goal can be met as he describes below? Also could someone point me to the tuning instructions for this beast. Thank you, Ted W3VG Original Message Subject: DB4379UHF combiner Date: Thu, 20 May 2010 11:16:13 -0400 From: Robert Harvey freedom...@windstream.net freedom...@windstream.net To: Ted Leonard n2...@verizon.net n2...@verizon.net Ted, you're the filter guy. I have a DB products DB4379-4404B 4 channel UHF combiner. You did a little bit of tuning on it once in the shop. Do you know, or can you find out, if it can be turned into two, 2 channel combiners? I want to combine 461.625, 461.650, 463.625 463.650 but the combiner is speced at 50KHz spacing. There are two splits of only 25KHz on the frequencies I need to work with. Combining 461.625 and 463.625 on one combiner and antenna and combine 461.650 and 463.650 on another combiner and antenna would save me antennas and feedline and lots of money if I can modify the combiner I own. Bob Robert D. Harvey Freedom Communications, Inc aka: RDH / TransCom voice (716) 664-2659 fax (716) 483-5968 email freedom...@windstream.net
RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
I would look for a shorted tantalum capacitor hanging somewhere on the 10V rail. I agree. If you hook 10V from an outside source to the 10V buss, you'll probably find it's drawing all kinds of current. The 10V regulator circuit will go into fold back before burning up. This is by design. I usually hook a source of 10V at about 1.5A and look for smoke. It's usually one of the tantalum capacitors that starts to smoke. Once it's done smoking, problem solved!! Put a DMM on the 10V line, then start disconnecting things until you narrow it down, divide and conquer. Pull all of the cards out of the cage (except the 10V reg card obviously), disconnect the exciter, remove the receiver, etc. With a good ohmmeter that measures fractions of an ohm, you should be able to narrow it down further once you've found the suspect module/board. I have lost track of how many shorted tantalums I have had over the years. When they occur in the B+ of the high current PA supply, they simply burn up and th problem fixes itself. They make a cool purple smoke with lots of sparks when they flame out! --- Jeff WN3A
Re: [Repeater-Builder] Techniques for combining multiple audio sources
what are you using? are Arcom? or Scom? If your using a arcom, take the jumper out of the delay board headers that jump the audio for each port, bring the audio out line (JP10-2,JP11-2,JP12-2) from each header into a mixer, run the output of the mixer to the audio input pin on the delay board, then just split the output of he delayboard however you want to, to the audio input pin on the delay board header (JP10-3,JP11-3,JP12-3), then you can set each tx level via the onboard pots. Not sure on the scom, have to look at a schematic. Thats the concept anyways. On Fri, May 14, 2010 at 2:49 PM, Jim (List) jim.l...@stuckinthemud.orgwrote: I'm in the process of building a repeater that will have multiple ports (3 different radios). Only one radio be receiving at a time, the other two transmitting. Therefore I have 3 audio sources (from different types of radio, at different levels), each being fed to the other two radios and requiring individual settings. In the middle of this I want to put a delay board, but to keep the cost down only have one. What's the best arrangement for combining the incoming audio, and then setting the levels for each TX? Thinking along the lines of a FET audio mixer for each RX, setting all to the same level of input to the delay board, then something on the output from the delay (would I need another series of buffers, or would three 100k pots do?) to adjust the TX level for each radio type? Thanks for any advice! Jim
[Repeater-Builder] Dayton to Evansville, IN
Leaving for Dayton tomorrow morning (weather forecast has improved a bit, looks like both Saturday and Sunday will be decent). After Dayton I'm headed to Evansville, IN. Any repeater-builders out there with machines between Dayton and Evansville (via Cincinnati and Louisville - I-75, I-71, I-64)? Got a new truck in March and still haven't had time to put the stack in, so will just have 2m and 440 this trip. --- Jeff WN3A
RE: [Repeater-Builder] Dayton
Our usual clan which includes a number of repeater-builder denizens will be in 2370 et al, at the end of a row. Come by for free 807's and bring lots of money to buy stuff, nothing I bring to sell is coming back home with me this year... Long-range forecast for Dayton doesn't look all that great, Sunday looks like the nicest day. The best deals are to be had in the rain! --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Andrew Seybold Sent: Thursday, May 06, 2010 10:42 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Dayton Our Flea market spots are 737-739, come by and say hello, second row, near the Bar. Andy W6AMS cid:image001.jpg@01CA5969.2F1EB460 aseyb...@andrewseybold.com mailto:aseyb...@andrewseybold.com 315 Meigs Road, Suite A-267 Santa Barbara, CA 93109 805-898-2460 office 805-898-2466 fax www.andrewseybold.com http://www.andrewseybold.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.819 / Virus Database: 271.1.1/2842 - Release Date: 05/06/10 14:26:00
RE: [Repeater-Builder] Re: CTCSS Encoder/Decoder
Building a PL decoder out of NE567's is old-school, and I've never seen a design that didn't have drift problems. The MX-COM (now CML Micro) tone chips were a better way to go, but many have been discontinued. If you can find them on the surplus market, that would be the easiest way to go. The part numbers were MX-3x5, where x was one of several numbers. Some were designed to be used with a DIP switch for frequency selection, others were designed to tie to a uP and took serial data to select the tone. Dig around for the datasheets, I'm sure they're out there... --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of tracomm Sent: Friday, May 07, 2010 10:14 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: CTCSS Encoder/Decoder I have to agree, unless you need to Reminisce about the good old days when men actually built the things they used, there are so many inexpensive options for ctcss that actually work, very well. There are a few Selectone units on ebay at about $2.00 and I am certain members here could supply more than a few boards very cheaply that actually work reliably. CJD --- In Repeater-Builder@yahoogroups.com, kevin valentino kevinvalent...@... wrote: Grab an old Standard HX300 or C734 etc. off ebay for practically nothing(if you find one) the enc/dec board is a plug in w/wire leads, very small, dip select, and rock solid. I have one kickin around with the schematic if your interested. I have adapted these to many old crap radios and they always work perfectly. Just a suggestion :-) --- On Thu, 5/6/10, James ka2...@... wrote: From: James ka2...@... Subject: [Repeater-Builder] CTCSS Encoder/Decoder To: Repeater-Builder@yahoogroups.com Date: Thursday, May 6, 2010, 10:35 AM Hi Guys, We have been experimenting with building CTCSS Units using the 567 Tone Chip and good components, i.e. Caps, multi turn pots etc. The stability is not good in my opinion. We will set it to 107.2 and the next time you check it is off enough to where it won't decode until it is re-tuned slightly. I am wondering what your experiences may have been with this CTCSS Chip. Many articles say they work well with the addition of a stable voltage regulator, so we added a five volt regulator, no difference in stability. Any comments and experiences with this and other chips would be appreciated. The availability of CTCSS Chips seems limited. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.819 / Virus Database: 271.1.1/2842 - Release Date: 05/07/10 02:26:00
RE: [Repeater-Builder] Skip At Dayton
Hi Skip, What Booth are you going to be in at Dayton?,Will you be going? Wesley AB8KD P.S. I want to see how Ugly you are There are plenty of people at Dayton much more ugly than Skipp - anyone who has attended Dayton before knows what I mean :-) When he's not mowing down pedestrians with a Hamvention security golf cart, Skipp goes slumming at our spaces periodically, stealing beverages and expensive items off the table. Beware of him. Keep one hand on your wallet at all times, and make sure your YL/XYL stays far, far away.
