In a posting about QSK Tom, W8JI wrote, and got me thinking:
"A set of 3CX800's can be ruined in just seconds of operation
with excessive grid dissipation."
I am working on a homebrew 8877 amp here and the circuit I am using for grid
trip is very common. It is a simple pot off of the cathode line to ground,
driving
a transistor which pulls in a relay. The relay breaks the PTT line. Here's my
question - the relay has a 100 uf electrolytic across it which slows down the
trip
time and also the time to reset, which is probably less than a second although
it
seems like forever. This time constant would mean that momentary overcurrent
in the grid circuit would be tolerated. Is this ok? I am considering lowering
the value of the cap or even eliminating it. If I eliminated it, then would
you think it would become annoying, tripping on little spikes.
Rick K2XT
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