Re: XV432 Oscillates with Amp connected

Posted by Stu2-3 on May 10, 2011; 11:19pm
URL: http://elecraft.85.s1.nabble.com/XV432-Oscillates-with-Amp-connected-tp6344925p6350043.html

Thanks guys!

It's quite weird. When I say key up, I mean activate the XV432 PTT with
the rig (exciter) in CW mode without pressing the CW key.  That is, no
RF goes into the transverter. Just the simple fact of keying the
transverter while it is connected to something other than a 50 Ohm load
seems to set up an oscillation.

Several people have suggested a pad. The output of the XV432 is a low
pass pi circuit. Since I don't want to reduce the RX gain, it would seem
this either needs to be in the amp's TX chain or the XV432's TX chain.
(i.e. before the TR relay)

After I wrote my first message, I installed an SWR meter between the
XV432 and amp so I could adjust the Henry for the best SWR.
Unfortunately, this didn't cure the problem. The XV432 still oscillated.
I have another amp I can try. I also have a TS2000 to try to help set
the amp up.

Thanks again for the ideas.

Stu2
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