[Top] [All Lists]

[Amps] Single Supply, multiple Amps switching

Subject: [Amps] Single Supply, multiple Amps switching
From: N7EME <>
Date: Thu, 10 Nov 2016 16:21:12 -0700
List-post: <">>
Hello All,

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

Amps mailing list

<Prev in Thread] Current Thread [Next in Thread>