One approach is to arrange the relay at the amplifier output to do the bias
switching - the relay may well stand 100 watts hot switched, but hasn't a
lot of hope at 1Kw +. I use a small relay on my linear, with no problems, as
the bias doesn't come off until the relay is over. But you do need some
chunky capacitors capable of handling amps of RF. I use the big 6 sided
Cornell Dubilier micas, 0.01mFd at 600v dc. They don't get hot at 1Kw at
3.5MHz. They are also often available cheap at hamfests. (10c at Dayton in
96)
73
Peter G3RZP
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