Reality Check; Dual Bias Supply for Bridge Rectifier

tictac · Post by **tictac** » Mon May 28, 2018 5:06 pm

Hi,

I have a PP amp with a bridge rectifier that I want a bias control for each tube. Any glaring issues with the circuit below?
Haven't seen it done before so thought I'd ask for a reality check before implementing...... Thanks!

YouTube · Post by **xtian** » Mon May 28, 2018 6:14 pm

No need for all that duplicate circuitry. Just feed your -ve bias voltage to separate adjustment pots, then to tube grids.

sluckey · Post by **sluckey** » Mon May 28, 2018 7:15 pm

Kinda like this...

tictac · Post by **tictac** » Mon May 28, 2018 7:34 pm

So basically you're saying the current draw on the bias supply isn't enough to warrant two separate circuit....

I understand you can increase C1 if you need more bias voltage as well....

Thanks for the replies....

TT

sluckey · Post by **sluckey** » Mon May 28, 2018 7:41 pm

roberto · Post by **roberto** » Tue May 29, 2018 12:20 am

Yes, because the impedance of C1 at the supply frequency, that is 1/(2 * pi * frequency * capacitance), together with R1 makes the first voltage divider for the bias supply.

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Reality Check; Dual Bias Supply for Bridge Rectifier

Reality Check; Dual Bias Supply for Bridge Rectifier

Re: Reality Check; Dual Bias Supply for Bridge Rectifier

Re: Reality Check; Dual Bias Supply for Bridge Rectifier

Re: Reality Check; Dual Bias Supply for Bridge Rectifier

Re: Reality Check; Dual Bias Supply for Bridge Rectifier

Re: Reality Check; Dual Bias Supply for Bridge Rectifier