[R-390] 60 Hz Hum Output from R-390A IF Module

[David Wise]

Modulation, not output. 

-----Original Message-----
From: rbethman [mailto:rbethman at comcast.net] 
Sent: Friday, May 08, 2009 5:35 PM
To: David Wise; r-390 at mailman.qth.net
Subject: Re: [R-390] 60 Hz Hum Output from R-390A IF Module

AN/URM-25s are NOT fixed ouput levels.  They can be dialed down to WELL 
under 1 uVolt.

These are what the R-39X series were worked over with.

I still use one today.  I've gotten my R-2000 to tweak in at the ZERO 
reading.

Bob

David Wise wrote:
> What percentage modulation?
>
> (Pardon me if the URM-25 is fixed-level, I'm not
> familiar with it.)
>
> Dave