Hi Anthony,
I noticed the same thing with my Omni VI a few years ago. (My Omni V didn't
have the noise ramp-up problem) It turned out to be the high level mixer
getting hot. (VERY hot to the touch) With the bottom cover off, it the
symptom never appeared. If let the rig warm up with the cover on, then
removed it, and I "hit" the mixer with some cooling spray, the noise would
drop back down. The easy fix is just to back off the RF gain to the 3 PM
position, or so. (A better fix would be to put some ventilation holes in
the lower cover)
73,
John W0DC
----- Original Message -----
From: "Anthony Bowyer" <adb1x1@yahoo.com>
To: <tentec@contesting.com>
Sent: Friday, January 10, 2003 7:31 AM
Subject: [TenTec] Omni V AGC Problem
> After having my Omni V on for several hours (15 or
> so), I noted what seems to be a bit of a problem with
> the AGC. There was a definite hiss increase that was
> very noticably mixed with a CW signal I was listening
> to. Turning the passband control more CCW, I could
> hear quite a bit more hiss than normal. The S-meter
> seemed to be functioning correctly and switching
> between fast and slow AGC did have some effect, but it
> seemed as if something in the AGC 'system' had too
> much gain. Looking at the diagram, it seems to be a
> fairly simple design, but I was wondering if anyone
> has had a similar problem with an Omni V or VI (I
> assume it has a similar AGC system) and repaired it?
> Maybe you could point me in the right direction.
>
> Thank you for any help!
> Anthony
>
> =====
> NT4X
>
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