>> "The purpose of this modification is to turn off the tube bias while in
>> standby or receive mode.
...snip...
>
>The Centurion amplifier I looked at had NO defective components, but
>sitting on a table just idling away 250 degree C temperature
>indicating paint on the anode seal melted right away after five
>minutes!
Yeah, but the hams in Alaska probably loved 'em in the winter time.
>
...snip...
>By the way, the "reason" given by the "engineer" for not cutting off
>tubes on standby was something about "not wanting to thermally shock
>the tubes because that causes tube failures". He showed me a
>statement in a certain non-ARRL "Handbook" that actually did say
>that!!!
>
Another 'old wives' tale' on ham radio. I have never seen a tube that
failed from thermal shock. Are you talking about Orr's handbook? ......
I have a copy of a rather eyebrow-raising letter Orr wrote to QST.
Rich---
R. L. Measures, 805-386-3734, AG6K
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