Jack -
Sent mine back to Ten Tec and they replaced the crystal oven with a
TCXO. Common replacement.
73 de K1ESE
John
Jack Mandelman wrote:
> When it is very warm in my shack (~85F) my Omni VI+ has the following problem
> on 30M only.
>
> Every 35 seconds or so the frequency would jump on the order of 10-50Hz for a
> fraction of a second, and then return. The symptoms suggest that the 30
> meter L.O. (on L.O. mixer board) is briefly losing lock with the reference
> oscillator (on logic board). At elevated temperature, I suspect that Y4 may
> drift slightly out of spec; the DC voltage fed back through connector 84 then
> corrects the oscillator frequency and regains lock. Perhaps an adjustment of
> 30M oscillator coil L19 would mitigate the problem.
>
> If the problem starts occuring more frequently I may want to slightly adjust
> L19 on the L.O. mixer board. However, my question is how to access L19 while
> keeping the 30M oscillator active. The L.O. mixer board is located under the
> FM and LL driver/NB boards, requiring disconnection of cables to access the
> board.
>
> I recall some discussion on the forum a while back about a similar 30M
> instability problem. I appreciate any suggestions about how to access the
> L.O. mixer board, while at the same time keeping the L.O. active. I did
> access the L.O. mixer board to fix an earlier problem related to an L.O.
> output filter, but totally removed the board at that time.
>
> 73 Jack K1VT
> _______________________________________________
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>
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