> in conjunction with the external everything would be OK, just as it was
> with the 120. That kind of leaves me with the impression that some kind of
> spur is being generated internally in the 940, and only on ten. I'm
> thinking that the internal tuner usage suppresses the spur and all is OK
> at the tuner. All reports on ten are that the rig sounds fine, and no
> complaints so far about out-of-band signals.
>
> Short of putting the rig on a spectrum analyzer, how can I verify this
> suspicion?
Hi Gary,
It is not unheard of that solid-state PA stages oscillate when
connected to some loads. In particular this would be true with a
high Q external load.
Solid state PA's normally have a lot of internal feedback. The off-
frequency reactance in a high-Q load can cause phase shift that
produces regenerative feedback.
I suspect you have that problem.
You might cure it by using a lower load Q, but unfortunately the
Nye tuner leaves you stuck with only one Q setting. You might try
adding a long chunk of extra coax between the rig and the tuner.
73, Tom W8JI
w8ji@contesting.com
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