Batboard

Have a UHF Quantar that developed a strange issue...It is Astro and has been working fine until recently...all of a sudden, the rptr will not key up except maybe once in 20 attempts from mobiles....Rcvr is ok (analog 0.25uV or so) and in analog mode, rptr is usuable 40miles away... but put it in Astro mode and NOTHING (except once in a while)...changed control card, no change......swapped with another Quantar where the other control card come from; no change!!! Programmed new freq, different NAC codes, no different....thinking it could be a problem on the input, took rcvr off duplexer and put a 1/4wave whip on it...100watt mobile 20ft away; no joy!! ARGH!!!
What could be the issue? Could it be I have TWO bad control cards? Left original rptr on and set to analog and Astro voice WILL pass through..but need to get it back into total Astro mode...Local Mot MSS could only tell me the 800# to Motorola Field Support...(thanks!!!) I plan to swap the control card with another good one and see if that cures the issue....RF seems to be ok and I tried everything I could think of..

What range is the repeater and what is the freq it is programmed with?

Also I am assuming its more than one mobile that is having issues getting in?


I recently bought a vhf quantar that came with 3 station control modules. 2 of the 3 were bad with the same issue (a little diff than yours).

If you need to I can tell you where to get a SCM CLN version for 250.

Jason

Have you checked the frequency calibration of the Quantar?

You'll need a good counter with an ovened timebase or just the timebase (GPS reference clocks are cheap these days) to do this properly. Don't rely on a TCXO reference. You're aiming for better than 1 ppm (less than +/- 500 Hz), adjust using the Quantar RSS service menu. You feed 10 MHz from your counter's timebase output or the output from your GPS standard into the Quantar’s external reference input and adjust according to the service screen.

Also are you certain ALL mobiles can't access? The reason I ask is that maybe one or two of your mobiles are off frequency. You can be way of frequency and analog will still work, get 500 Hz off on Astro and you're stuffed.

Well it was not off freq or anything similar....another tech went to the site..and reloaded the codeplug from another site into the Quantar and reset freq and hex codes...it worked! I HAD done the same thing but not sure why it didnt work when I did..there was some questions on some filtering in the rcvr but then that HAS been in the codeplug for over 2 years! Strange how it got wacko but at least its working ok now in Astro mode.....