I had a number of QSO's with K5CX on both SSB and CW before he became a
silent key. He was using a home built QSK diode switcher on a 3-1000
linear amp. Instead of a power PIN diode, he used a Diodes Inc. 6A6
power rectifier. He tested this circuit at powers up to 2kw and measured
no change in the 3rd and 5th order products and harmonic content using
his HP 141T spectrum analyzer. Jim sent me a circuit diagram and page of
notes on how it operates. I have not met him personally but he seemed to
be a skilled engineer. One of his projects was a 600w power fet linear
which sounded great.
I have jpegs of the 2 pages and am willing to share them with anyone
who would like to try the circuit if I don't get buried in requests,Hi.
I believe I saw somewhere in one of the ham magazines info on using
something like a 1N4004 as a 2m r.f. switch.
I am sure there are people on this reflector who can tell us about the
pro's and cons of this and possibly have tried it. I checked the Diodes
Inc. web page and found that DigiKey stocks these devices as well as
some with higher voltage ratings in the same series. They are epoxy
cased jobs and should be pretty inexpensive, I think. I should mention
that Jim used sheet copper mounting plates on each end of the diodes.
73, Dan, N5AR
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