Using one half of pt ht secondary with full wave bridge???

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mauiboy81
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Using one half of pt ht secondary with full wave bridge???

Post by mauiboy81 »

This may be crazy.... I have an old power transformer that has 430-0-430 secondary. That is just too high so is it possible to do something like wire a bridge rectifier between the center tap and one leg?
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martin manning
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Re: Using one half of pt ht secondary with full wave bridge???

Post by martin manning »

If you put a full-wave bridge on half of the secondary you'll get the same voltage as you would using a full-wave and both halves, except you'll lose about half of the current capability.
Firestorm
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Re: Using one half of pt ht secondary with full wave bridge???

Post by Firestorm »

If you build what is usually called an "economy" power supply (where the pt center tap is connected to the middle of series filters) -- some Marshalls do this, some Ampegs-- you get half the voltage at that point (the center), but also only half the current capacity.

You could put a reverse biased Zener between the center tap and ground, but I would only try to drop maybe 75V that way and the Zener would have to be rated for many, many watts (well, you can also "stack" them).

But IMO, you'd be better off regulating the B+ with a VVR/power scaling type control. Doesn't even have to be adjustable (but why not).
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