[R-390] Distortion

Mon, 7 Apr 2003 17:56:17 -0400

The geared shaft going into the Antenna Trim can is at a high impedance...it
"ses" the front end AGC line.  If you mistakenly lubricate the gearing and
saturate the phenolic sleeve, it may begin to show enough conductance to
drag down the AGC line.  Some people mistakenly lubricate these gears and
saturate the sleeve...not a good idea.  Get a trichlorethane or equivalent
moisture displacement spray and clean off the shaft and gears, especially
the phenolic sleeve under the gear.

----- Original Message -----
From: "David Wise" <[email protected]>
To: "K2LNU" <[email protected]>; "R-390 Reflector"
<[email protected]>
Sent: Monday, April 07, 2003 5:28 PM
Subject: RE: [R-390] Distortion

Roy mentioned tubes and IF gain.  I'll add C551,
the AGC filter cap.  It's frequently leaky.
If the problem clears up when you switch AGC
to FAST, that's it for sure.  If it gets better
but doesn't go away, check C548 too.

73,
Dave Wise (SWL, Portland OR)

> From: K2LNU [mailto:[email protected]]
>
> Hello R-390A Fans,
> Can anyone tell me a probable cause for an R-390A going into
> distortion when
> the RF gain is turned up above 5?  Any ideas are greatly appreciated.
> Bill K2LNU
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