[Elecraft] KPA500 Problem

[Brian D]

Kevin der Kinderen <kkinderen at gmail.com> wrote:

> I'm a bit surprised that's the conclusion as simply bypassing or turning
> off the amp but leaving it connected made the problem go away. I have some
> good cable on there now but can replace each one of them to try it out.
> I'll report back later on. I really hope it is just this.
> 
I had a similar problem recemntly due to a SC diode in the TR switch, all OK
on bypass but not on operate. After changing diode (and checking associated
bits I has problems with power/dissipation on 10 and 6m cured by using a
diode from a different batch.

However, after re-assembly I had intermittent lack of RX, traced to a relay
card used externally for buffering a relay. At the time this board was
unpowered but still in circuit and was holding the KPA500 on TX. A simple
bypass proved it was the culprit and putting its 12v power back on fixed it
for good.

-- 
Brian D
G3VGZ  Yarm    England