If you have a stable general coverage receiver you can listen to each of
the oscillators to see which one is drifting. May have to experiment with
methods of getting a sample of each oscillator to the receiver.
On Wed, Jun 27, 2018, 19:06 Bob McGraw K4TAX <rmcgraw@blomand.net> wrote:
> I start with my original suggestion for old radios such as this. "Clean
> connectors". All of them. One at a time, unplug the connector, using a
> Q-Tip with contact cleaner applied, scrub the male pins. Then push the
> connector on and off a couple of times to wipe the female contacts.
>
> Drifting.....is the master oscillator drifting? Could be the oven
> cycling excessively. Or could be a BFO crystal, although that would
> likely affect all bands. However, they are in the rear near the PA and
> the heat migrates noticeably into that area. They are really not
> temperature compensated.
>
> Yes, you can tweak the coils on the band oscillator board to get them on
> frequency but usually something else is causing drift. Bad BFO cap has
> been known to do this.
>
> Check the BFO alignments per the manual, and in the order defined for
> all modes using a frequency counter.
>
> 73
> Bob, K4TAX
>
>
>
>
> On 6/27/2018 8:38 PM, Stan Gammons wrote:
> > Hi Everyone,
> >
> > My Omni VI has decided to throw a few more fits. First the frequency
> > jumped on 30 meters, but FT8 signals still decode fine. So I let it go
> > and didn't mess with it. Lately 40 meters has started throwing fits
> > and it's much worse than 30 meters. Looking at the FT8 waterfall, at
> > times it will drift during the 15 seconds and it's bad enough the FT8
> > signal won't decode. I sent another email to the list with the
> > waterfall pic attached, but the message was too large and got
> > rejected. I tried tweaking the coils on the crystal oscillator
> > board. It might have helped 30 meters a little. Doesn't seem to have
> > done much/anything for 40 meters though. Crystals gone bad maybe? If
> > so, anyone know a source now that ICM is no more?
> >
> >
> > 73
> >
> > Stan
> > KM4HQE
> >
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>
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