4-channel Quickie

marty51 · 4738

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Offline Paul Birkeland

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Reply #15 on: May 29, 2014, 05:00:37 AM
Your drawing doesn't have separate grounds.  V1 and V4 will have filaments that sit at about 13.5V, V2 and V3 will sit at about 25.5V.  This is the bias applied to the tube itself, and when you try to put a cathode resistor in, you'll be providing a path to ground for battery current.

You'd need a separate cell for each 3S4 regulator, then a stack for the B+.  You might be able to find a filament transformer with four 5V windings, which would help get you where you need to go.

Paul "PB" Birkeland

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Offline mcandmar

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Reply #16 on: May 29, 2014, 05:22:24 AM
Or if you really want to stay battery powered use four 6v SLAs feeding into four separate LM317's.  Its going to get big and heavy real fast..

M.McCandless

Offline Grainger49

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Reply #17 on: May 29, 2014, 05:44:55 AM
I'll throw some thoughts at you.

Dropping 12V to 1.2V will waste a lot of voltage and heat the regulator in doing so.  Maybe you can find a 3V SLA?

I tried floating the ground on a PAS-3 preamp and it didn't work.  Try it but be prepared to try a ground too.

Here is hoping it all works!


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