GTX No Tx at 927 sometimes

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kb8rst
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Joined: Mon Jun 03, 2002 4:31 pm

GTX No Tx at 927 sometimes

Post by kb8rst »

Trying to use a GTX M11WDG4CB1AN at 927.6125
makes power but the vco seems like it not locking
some times it works but most of the time not
floats at 928.????

Thanks in advance, Mark
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kcbooboo
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Post by kcbooboo »

There doesn't seem to be an adjustable VCO in the GTX like there is in the MaxTracs; that's the first thing that came to mind.

Some of these radios output considerably less power at, say, 927.5, than they do at 927.4875 or even 927.6 MHz.

Did the radio accept the programming, i.e. are you using a modified version of the program that would allow out-of-band frequencies to be entered? It almost seems like the radio took the freq, but for some reason doesn't realize it can work at that freq. There are several places where the band limits need to be changed - maybe you missed one.

That's the extent of my troubleshooting abilities on this one. Very strange.

Bob M.
kb8rst
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Joined: Mon Jun 03, 2002 4:31 pm

Post by kb8rst »

Thanks Bob
I think the SW is ok been using it for a while now
did 2 radio's and 1 works fine

Thanks Again Mark KB8RST
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kcbooboo
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Post by kcbooboo »

How does the receiver work at this frequency? Does the transmitter work at other direct freqs, and what about down at 902 MHz? How does it run if programmed to its "normal" freq range?

If you have another radio that works properly, maybe you can clone its code plug into the "bad" radio. That seems to be the cure for those GTXs that output very little power on 927.5 MHz.

The manual says there are two VCOs: one RX/TX that runs 45.1 MHz below the carrier freq for RX and at the carrier freq for TX in the 896-902 MHz range, and the other that is for TX only at the 936-941 MHz range (talk-around).

You'll probably need the service manual for further troubleshooting.

Bob M.
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