[TenTec] drift on 160, omni 6

[Ken Brown]

Hi Jason,

Since it only happens on 160 meters, I would suspect Y1 on the XTAL OSC. 
- L.O. MIXER BOARD (81595). That is the 160 meter band select crystal. 
It is supposed to be "locked to a precision reference" according to the 
narrative description of that board. My guess is that the adjustment for 
that crystal, L12, needs  to be twiddled.  There is a " DC Correction 
Voltage" to this oscillator. I would measure that voltage when using 
various bands that are working right, and then see what is happening to 
that voltage when on 160. You may be able to tweak L12 to get that 
voltage back to something close to what it is on the working bands. If 
so, the problem will likely be solved. My guess is that L12 is so far 
out of adjustment that the DC correction voltage is all the way to 
either maximum or minimum of it's range, and cannot keep the oscillator 
locked when on 160 meters. Another possibility is a flaky crystal.

Good luck, have fun.

DE N6KB

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>I have an Omni 6 that works fine in every way except a slight drift on 160
>meters.  Every 2 seconds it drifts downward about 20hz and then comes back
>to the original frequency, then drifts down again, continuously.
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