Using PT 5 volt Winding to Lower B+

[kinmike]

Guys,

I've had B+ voltages a bit high on one of my builds and I heard about using the 5 volt winding to lower it. Is this a valid technique? I know the 5 volt yellow/white lead from the PT is unused on the normal wiring (and on my build).

Can you explain the concept and tell me how to hook it up?

Thanks,

Mike

[crgfrench]

I have never done it, but I too read about this somewhere. The idea was to wire the unused secondary in series with the primary which would effectively lower the turns ratio. Someone pointed out that while possible, this might not be safe since it eliminates the isolation between primary and secondary.

[dogmeat]

maybe a zener. theres a bunch of stuff out there about it. heres one from Webber

https://www.tedweber.com/v-dump

[Daviedawg]

Zener diodes are a sound option for reducing the B+. I have not heard of let alone used this option.

Dd