Dr.Johnson makes a good point about the possibility of stray RF tripping
the magnetic circuit breaker in the power supply. I'll try a couple of
shielding and bypass techniques.
In answer to Don Kemp's question: the problem occurs even when the SWR
is flat (on my lab grade dummy load) with a short coax run straight to
the load. At any rate, my antennas are resonant to within a 1.7:1 SWR
at worst (double bazookas). Since no changes were made in the station
setup, the sudden appearance of the problem leads me to suspect a
component failure upon powering up. I'm hoping it's in the power supply
-- a Model 225. Electrolytics are always a reasonable suspect.
Since I'm primarily a tube guy, I have a question about solid state
finals. Do they ever "go soft" or invariably fail catastrophically?
Ten Tec suspects the finals may be bad, I can get full output from them
if I increase the circuit breaker trip point (but, of course, I don't
wish to operate the rig in this manner). The circuit breaker is
triggered by excessive current draw (10A), but I don't understand how
the finals themselves could play a role in that. Would someone please
explain?
73,
Craig
W3CRR
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