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Re: 847 bi directional CAT baudrate



> This work's great on AO-40 as your d/l isn't very stable due
> to temperature variation's causing the down converter to drift in
frequency.

I found this to be true even for D/Cs with ovens.  I eventually moved the
D/C into the shack and put a low noise (.6 dB), high gain (37dB) DB6NT
preamp on the patch feed which feeds a 10 ft. section of LMR-600UF
(Ultra-Flex) connected to another 75 ft. of regular LMR-600 running into the
shack.  Having the D/C in the shack has reduced the temperature-based
frequency drift from +/- 7KHz to +/- 1000 Hz with much of what remains
undoubtedly being variations at the bird itself.

I use the Uni_Trac for doppler tuning and rotator control with its control
software being managed over a DDE session by Nova for Windows.  When I fire
up my AO-40 station, I can hear myself immediately on transmitting and use a
slider on Uni_Trac's control SW to quickly fine tune my TX frequency.  From
that point on I'm all set to move around throughout the passband with
Uni_Trac automatically providing the right TX offset.

Now if only more operators would use full doppler tuning...

73 de Rick, KG6IAL



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