Carey,
Yes that sure sounds like a problem on the LO / Mixer board. Could be a
failed crystal but also may be a bad solder joint, trimmer cap, or
something along that line. The best way to track it down is with a
frequency counter and a scope probe.
When my Omni-V was in last time, they did a few good updates. However
they also soldered a wire across all the crystals on the LO grounding the
cans. I don't really know the reason for this but it made the warmup time
drift take much longer due to all the mass of solder etc. I took this
soldered mod off and cleaned the cans off best I could didn't notice any
change with the performance but warmup was faster again. (!!! Don't
mess around with any of this unless you have a good freq. counter and
know how to calibrate the board!!! ) After doing this I had to re
calibrate every band.
I only mention all this to explain a reason a crystal could fail after
service, it may have been in poor shape to start with and heating it to
solder put it over the brink. If this is the problem it will drift the
same on transmit so that's one way to check. Not a big problem just too
bad about all the shipping etc.
The only thing I could suggest if your not up to trouble shooting and
want to send it in is to remove the cover on the pll / lo can first and
just make sure there's not a loose plug or something. Who knows you may
just see the problem!
Good luck es 73, Jeff aa8ve
Omni-V is one of the most amazing rigs them hillbilly's ever came out
with!
On Sat, 30 Oct 1999 08:36:23 -0400 "R. Carey Brown" <cbrown@exis.net>
writes:
>
> I'm hoping someone may have experienced similar problems and might
> have some suggestions. . .
>
> Problems:
>
> 1. Noticed on (40 M only) that when I first turn on the rig, the
> receiver is initially dead (the one time I tried, the rig would not
> transmit on 40M either). Waiting time varies from 30 seconds to as
> long as 4 minutes before receiver finally "comes to life" and
> operation is normal after that until turned off and left overnight.
> On all other bands, receiver springs to life on power-up.
> Discussed with TenTec, who suggested that this is possibly an aging
> crystal.
>
> 2. While operating, noticed RX began to sound just like "buckshot"
> used to sound on my old Drake 2B on 75 SSB when a station camped
> about 4 Khz away (but this sound started occurring on CW, rather
> than SSB) this behavior made no sense until it worsened and I
> realized that CW signals were rapidly changing frequency in such a
> matter that signals "flew through" my passband at such a rapid pace
> that they were unintelligible. I don't know if the same thing was
> happening to my transmitted signal or not, as I immediately took the
> rig out of the lineup.
>
> I have owned this rig for 10 years and never experienced any such
> problems until I developed an intermittent transmit problem, which
> TenTec corrected by replacing K1, D2 and R4 on the low pass filter
> board. They also replaced the main tuning encoder and the 20 meter
> band push button on the key pad.
>
> While they had the rig, I asked TenTec to do the "hiss mod" on the
> PBT, IF/AF boards. They also replaced D10 on the bandpass filter
> board and installed the latest software on the logic board and added
> a regulator board to logic B+. Finally, they performed alignment of
> the PLL, BFO and RX.
>
> I fear the requested alignment may have led to the present problems
> - one of those "if it ain't broke, don't fix it" situations where
> everything had aged 10 years and realignment disturbed the "natural
> balance" of things. Dunno.
>
> I am packing this up for return to TenTec, but felt it might be
> worthwhile asking here before taking the next step - Has anybody had
> similar problems? Any suggestions (other than returning rig to TT
> again)?
>
> Thanks - Carey
> KT4P
>
>
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>
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