Just joined the group and have a question concerning switching multiple
amps with one supply.
I have a single Peter Dahl xfmr that I designed a power supply with and
want to use it with multiple
amplifiers. 1175VAC @3 amps with a doubler giving about 3325VDC.
I have a 6 meter GS31B G-G amplifier currently running on that supply,
but have plans for 2 meter and
70cm G-G amps using GS31B's as well.
Between the power supply and the amplifiers, I have a control panel that
switches the Plate Current meter,
Grid Current meter and a PTT enable line, that gets grounded for each
amplifier when selected. Filament
is supplied by individual xfmrs in each amplifier and is floating above
ground, no center tap, etc...
BUT.... I will have the High Voltage always present on each all the
tubes after a 3 min timeout,
and the Filaments and Blowers will be running on each tube. Any amp
currently selected by the control
panel is bias off at about -56 volts until the PTT line for that tube
in enabled. Resting current is adjusted
for 100ma of Plate current when idle. This much works great right now
with the single 6 meter amp.
My question is, can I apply Plate voltage along with just the Filaments
and Blowers on a tube,
and have the Cathode and Grid metering open, and not cause any damage?
I believe I can because there is no current path for Cathode current or
Grid current for the un-selected
tubes. I need additional confirmation from someone with a little more
knowledgeable than myself on such matters
Jerry Mulchin - N7EME
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