Chad, WE9V wrote:
>For reasons unknown (Rich, Tom, Karl comments??) we had terrible luck with
>this. A high percentage of the time, for turn on, the RF deck would draw
>a TON of current, blowing up all of the RF deck annode components up to the
>tube, a fuse resistor in the power supply, and most expensivly, the vacuum
>relay. I don't know how many hundreds of dollars were spent on replacement
>relays, but we finally went back to 6 power supplies for 6 RF decks.
>
Hi, Chad! Been there, done that. You cannot switch D.C. with a vacuum relay
with any voltage present on the contacts. Also you must also put a relay in
the B- returns or all your meters will read wrong. What I ended up with was
a giant ceramic 3 wafer rotary switch. This allows using it as a "band"
switch,
bringing up each individual amp's B+, B-, and keying circuits, one at a time.
(((73)))
Phil, K5PCV
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