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Xtrchessreal Xtrchessreal is offline
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Default B Field collapse

On Friday, August 4, 2017 at 11:37:24 AM UTC-6, wrote:
In common power supplies the only example where there might be a problem would be that using choke input. The choke likes to keep the current flowing, so a switch between the rectifiers & the choke input could cause insulation failure. But a switch on the primary side as it normally would be is OK, the choke still has a way to dump stored energy thru the PS transformer wdgs & rectifer.

But choke input is now uncommon, most PS are cap input.

In my case I installed the fix I spoke of in a regulated PS with DC standby I built many years ago so that it can be run either in choke or cap input. The max volts or current can then be used to advantage.

Cheers to all, John L Stewart


its a 2204 Marshall circuit that I built, I added an LED between the input filter and the standby, when switch closes and B+ hits the amp rail LED ON, such that when switch is later opened the Caps discharge through the LED to ground over a period of several minutes, for safety when opening the amp e.g. to bias new tubes or repairs, tweaks...

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