DC heater supply from 5v tap

[afm_380]

I'd like to off-load the preamp tubes heater circuit off of the 6.3v tap to free up the current to run a pair of el34's in one of my recent 6V6/6L6 builds (it would probably be easier to just buy a PT that has higher rated 6.3v tap ... but what's the fun in that?). I'm running a solid state rectifier, so I have the 5v/3a tap sitting there unused ... I should be able to build a rectifier bridge with 4-6amp diodes and regulate the 7dc volts I get with the 7805's floating above a string of 1n4007's to get me back down to 6.3volts ... WhaChYa Think?

[Tom Phillips]

IMHO I think you can make it a lot simpler.
The rectifier bridge will probably give you closer to 6.4 VDC (with the filter cap) due due to the forward voltage drop of the diodes in the bridge itself. Just connect all the pre-amp tube heaters to that output. Add a little additional dropping resistance if you want to get exactly 6.3V. However ~10% over voltage will not be a problem.
Regards,
Tom

[afm_380]

In my 'day job' I am always preaching the KISS (keep it simple, stupid) theory in my design efforts ... I keep getting carried away when it comes to my amp design work ... Thanks for the Reality Check