Batboard

rocketman

The original poster stated UHF....and judging by his description of the terrain, one would have to surmise some sort of repeater would have to be employed in the mix...25 to 50 miles on UHF simplex under the stated conditions won't happen

rocketman

I totally concur with the above post regarding radiation pattern characteristics. Have done extensive testing with a similar situation and we finally found that the 1/4 wave was the antenna of choice. In valleys and behind hills, the 1/4 wave shines....the gain antennas were just dumping signal into...

rocketman

Before you order any antennas, you need to check your license to verify: 1. allotted power output per the license, and 2. ERP as allowed by the license.

rocketman

I have a repeater system (UHF) in Southern Connecticut that used to have the same issues. I cured it with several satellite receivers in strategic locations with moderate to high gain antennas and the main site at a very high location with a moderately low gain antenna (5 dB). Problem solved....most...

rocketman

I have had this happen B4. Voice peaks were going over 0 dBm....causing guard tone issues and the locked comparator until she timed out after 15 seconds or so.....I lowered my audio levels and problem went away.

Rocketman

rocketman

I sent an e-mail off to the nerepeaters crew advising them of the situation, and requested a change in their database reflecting the HearClear status.

Rocketman

rocketman

All three Connecticut machines are running hearclear. This would be Guilford (927.4875) Hamden (927.4125) and Branford (927.8125).
I maintain the Guilford machine and personally know the owners of the Hamden and Branford repeaters.

Rocketman

rocketman

the receive VCO can be adjusted to bring the SL voltage more in line.

rocketman

sledgehammer

rocketman

http://www.repeater-builder.com/motorol ... rctrl.html

A search on the web would have found this document

Rocketman

rocketman

Matt, They got exactly what they deserved. Although it does not bode well for the citizenry needing municipal emergency response, this proved the point you made. Management is often clueless on the real nuts and bolts, looking at the dollar signs only. Like my old saying, a masters degree does nor n...

rocketman

MDC 600 or 1200 is not just for public safety. I have no idea where your club president got that hairbrained idea. Utilities use it, and regular business band users employ it also. I know where I work it keeps the horseplay off the air, as we know who is fooling around and those who fool around on t...

rocketman

Matt,
I was able to understand you fine, although the audio was a little bit bassy. Was this the recording off the console?

Dave

rocketman

probably bad SM caps-the Spectra is well known for this problem.

rocketman

I would not even screw around with LMR or 9913 for repeater use. Depending on cable lengths, use Andrew Heliax 1/2" or better. We are using 7/8" for our 900 repeater here in North Guilford, CT. Losses dictate the largest cable that you can install. And yes, do not use crappy jumpers or con...

rocketman

that hook is there for strain relief so you don't yank the microphone plug out or otherwise damage it by yanking....it is supposed to be fastened down to be effective in its task

rocketman

the audio preemphasis/ flat adjustment will depend on the setting of the radio system.....is (are) the receiver(s) set for deemphasis....if so, use the preemphasis setting....if they are set flat, use flat. Otherwise the wrong audio setting will make the transmitted audio sound like crap

rocketman

once the self chk display comes up, you must at that moment turn up DC voltage up to normal

rocketman

ended up changing out the command board and now all is well...I am guessing a problem with the SM caps...

rocketman

Okay, I dumped all the conventional channels out of the radio except for the 1 trunking channel, now the radio does the self chk/fail 1/90 loop. The fail loop is only visable with power supply voltage lowered to 6-7 VDC. I cannot read the radio, as the serial bus is constantly busy....any thoughts o...

rocketman

Not sure if this has been discussed before. I have a D27 Spectra and for some reason, it will not transmit either a PL or DPL. I checked the programming and it shows correct. This also happens in direct (talkaround). It receives PL and DPL just fine. Audio deviation sounds good in carrier squelch, a...

rocketman

If you are going to use it as just a receiver, I don't think you want to go to all the extraordinary effort to make it 32 channels....your decision of course....you can use ordinary firmware...just blank and initialize it as an 800 mhz radio, cause that is what it is. Program in the Out of band freq...

rocketman

I have messed with the D37's and B27's. personally, I would initialize the radio as a B3 so that the radio does the talkaround or simplex instead of adding additional stuff. In case you want to also use it for repeater use, forcing the radio to the right VCO will take that option away.
Dave

rocketman

My only experience with 900 Maxtracs turned down (about 1.50 watts) was with a 12 watt unit. It looked stable both in terms of a spectral analysis and operation. We used it as a repeater exciter until we got the Nucleus II up and running. I'm not sure about the 30 watt unit being as stable. I have b...

rocketman

if you have the advanced controller, audio can be dumped into J-17 pin 3 for positive and pin 28 fro negative input. This is also known as punchblock pair J17-3 (line one input). If you have a J-61 present, the audio can go here instead, as it is a piggyback of J-17 pin 3. depending on the wireline ...

rocketman

I would go with DPL, less chance of falsing, assuming you are using a community deck

rocketman

yes the GM 300 does MDC1200 either pre or post....and no you cannot change the existing MDC without the correct overlay file....it sounds like the version of software you are using is lacking that overlay file

rocketman

I would imagine a 1/4 wave will work well, especially in hilly terrain. As you know, we prefer 1/4 wave on 440 (they work better in our terrain than the gain antennas). It is certainly worth a try, especially in light of the garage opening issues. Plus a 1/4 wave is cheap and broadbanded.

rocketman

I would not even bother with a multi-band antenna, especially when it pertains to 900 mhz. It is a compromise. i would go with a monoband antenna, and not worry about the hassles of antenna loss, pattern disconfiguration, diplexer loss, etc. 900 mhz is too lossy a band in mobile instances to even sc...

rocketman

Can the Micor TLE 1252A PA move easily into the 902-928 band?
Will it require drastic modifications to do so.
TIA, Dave N1OFJ

rocketman

I don't have a manual for the Maxtrac D27. Does anyone know where the Left VCO voltage test point is located.
Thanks in advance, Dave

rocketman

Matt, you need to use an aftermarket board as previously mentioned...4 link radios on .475 are M1225 and they all have aftermarket MDC boards installed in them., even though they are being used as receivers....I have the pinouts somewhere .....there are some minor mods to the radios to accomodate th...

rocketman

Okay, thanks....I located a manual from a unified chassis model that has the PA schematic...8 VDC for max makes sense with what would normally feed the control line from the power control circuit ...thanks again.

rocketman

I have obtained a UHF (450-470) Micor continuous duty PA. There is a yellow wire soldered near the power supply input marked control, which I'll assume is used for power output control. Since I do not have the unified chassis that came with the PA and the associated power control board, what is the ...

rocketman

Just sent a donation via PayPal...keep up the great work!

rocketman

Does anybody know what a 450-470 Maxtrac exciter should provide for output power. Are there cables that would adapt the stock exciter output to a n-connector?
Thanks, Dave

rocketman

check PM

rocketman

approximately 4.75 VDC either active high/low depending on programming

rocketman

Sounds like your ambulance company needs to add a satellite receiver somewhere in that valley area. That should help TX out of the valley.

rocketman

Is there a way to program frequencies below 440 MHz. Using the shift key, I can get the radio to take frequencies below 450, but nothing below 440. Any ideas?
Thanks,
Dave

rocketman

Glass mount antennas are a compromise for performance. Personal experience has found a body mount (NMO) provides the best performance. Depending on the needed bandwidth, a 1/4 wave should perform well over a wide frequency range.

Search found 41 matches

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Re: Connecticut 902 Hear Clear status

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question about a Micor Continuous duty PA TLE 1713A

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