Thanks for the info Don.
Yes, I've double checked, and none of the oscillators I can find on the
schematic are powered directly by the incoming +Vcc, all are powered from
REG+ 8.5v or 5v in the PLL compartment. Which ones in the OMNI VI+ are
powered directly from +Vcc? I'd have thought this wouldn't be good practice,
running an oscillator from the main power bus that is likely to fluctuate?
I will replace the screws that are missing, as you say this may be the
answer since TT use the mounting points as earth routes as well. I had to
isolate the sidetone board from the chassis, as I was getting a lot of
talkthrough on the internal speaker and the headphones. This cured the
problem completely.
I did buy the radio used, one previous owner. It was deaf on RX, due to a
faulty external RX ANT switch. He's a good friend of mine, and did mention
that he had sent the radio off a couple of times for repair. It was cheap
tho'! :-)
I'm still waiting for the agc hiss modifications from TT by mail.
Once I have these 2 problems solved, the next step is one of Carl N4PY's v.9
microprocessor replacements. I'm looking for a source of the processor
MC68HC705C8ACP here in the UK, otherwise I'll have to order from Newark
Electronics.
Thanks for your input!
Paul MW0CDO.. another glorious sunny morning here.
----- Original Message -----
From: <VE1BN@aol.com>
To: <gw7lhi@hotmail.com>
Sent: Saturday, March 30, 2002 12:46 AM
Subject: Re: [TenTec] RE: Omni V Fm'ing
> Hello Paul -
>
> Thanks for the reply.
>
> Must admit I am still curious about a regulator for +8.5 volts. Don't
recall
> ever seeing one. If your schematic says that, then guess I will have to
> accept it (ha).
>
> About the missing screws, yes they should definitely be replaced. Two
sheet
> metal types hold the TX audio/BFO board mounting bracket to the back
panel.
> Better grounding and mechanical stability when you replace these! May be
the
> fix you are looking for? Ten-tec boards usually ground through mounting
> screws to complete short earth paths.
>
> Odd they are missing, but then I seem to remember you saying something
about
> getting your OMNI from a previous owner.
>
> My OMNI is a 6+, not a 5. The screws to be replaced on yours are in the
same
> location.
>
> Hope this helps. Good luck, Paul.
>
> 73 - Don
>
>
>
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