Thanks for the suggestions and information...
I have to figure out if I have the time to tear her down a bit and change
the 20 MHz reference oscillator, then tune each band crystal to see if it
comes back into range.
Does anyone have a diagram that shows the layout on the board for the band
crystals? The drawings in the manual don't show which adjustment
point/crystal is for which band.
Thanks!
John
K2JNC
On Fri, Feb 24, 2017 at 9:44 AM, Dukes HiFi <dukeshifi@comcast.net> wrote:
> I do not consider Omni 6 radios at EOL.
>
> They are usually easy to fix and great performers aside from their raucous
> sounding SSB receive audio.
>
> Do you power your power supply off when you turn off your radio?
>
> If so, you are allowing the oven to cool and there will be a significant
> wait time for stabilization anyway even if the over is still working at
> all. Failure of the reference crystal oven is quite common in the older
> Omni 6 radios. That is why Ten Tec changed to a prepackaged 20 MHz
> reference oscillator in later versions. These fail too.
>
> Since you have SO many bad positions, it is unlikely that your problem
> rests only with bad crystals anyway. More likely the reference is off
> frequency snd is drifting.
>
> Several have suggested in previous posts that you can install one of the
> many prepackaged thermally compensated crystal oscillators available from
> Mouser or Digikey as the reference. The frequency is 20 MHz. This is a very
> good suggestion.
>
> These devices were not available when the Omni 6 was first designed.
> Installation is very easy and the end result is better than the original.
>
> You will need to realign the crystals that are still within range but some
> may need replacement. These can be had either f rom junk radios or from a
> few on line crystal suppliers.
>
> Once you follow the alignment instructions for one band that seems to
> align up properly, follow through with the others and see how many of them
> pull in. Chances are that most will once the reference oscillator problem
> is corrected.
>
> Gary
>
> W0DVN
>
> > On Feb 23, 2017, at 4:58 PM, John Callari <john.callari@gmail.com>
> wrote:
> >
> > Hello all..
> >
> > I recently acquired an Omni VI... After warming up, some bands are dead
> on
> > (17M, 15M), some are off a little bit (40M, 80M) about 500 Hz and 20M is
> > off by nearly 1.5 kHz.
> >
> > I've worked on some of my older Icom rigs (751, 745, 765) and was able to
> > re-calibrate them and re-align... but that was following the service
> > manuals...
> >
> > Any suggestions on the best way to fix this... From what I've read and
> > looking at the manual, I'm guessing that my problem is with the band
> > crystals on the XTAL OSC/ LO board...
> >
> > Any help would be much appreciated.
> >
> > Thanks!
> >
> > John
> > K2JNC
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
>
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