[Collins] (no subject)

[Dr. Gerald N. Johnson]

On Fri, 2006-06-02 at 17:30 -0400, walnutcreek at appstate.net wrote:
> I have a squeal on it after the 1/4 af gain.  It started while I was going to get some water at the
> house and then heard it.  Is then problem in the 516f-2?  There is a buzz from the transformer.  I
> fixed it two years ago with new elec. caps and so on.  I'm wondering about the problem and don't no
> where to start other than replaced the tubes one at a time. Help!
> 
I presume you are talking about a KWM-2 because that's the only receiver
using the 516F-2.

There are electrolytic and paper power bypass capacitors in the radio
that also go bad.

Check the bias supply, especially the rectifier (selenium doesn't last
this long) as not having cutoff bias for the transmitter will let
transmitter and receiver circuits run at the same time and there will be
all kinds of assorted squeals.

-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer