Simple question: Will application of 20 or 30mW of RF damage the tubes when
they are not "ready" ?? It looks like the 8122s can handle a couple watts of
grid dissipation each - is this relevant if they are driven when not "ready" ?
On my RF-110A's, I added a second coax relay outboard, just like the one that is
inside the RF-110A
case. They are powered by 28 volts dc from the RF-110A. Until the amp has done
its start-up
timing sequence and is ready to transmit, the exciter RF is routed directly to
the antenna. When the
PTT is activated on the exciter, the DPDT coax relays switch the amp in line.
Most users need this
anyway when a transceiver is used to drive the amp. If a fault is detected in
the amp, 28 volts will
not be available to key the relays.
(((73)))
Phil, K5PC
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