The copper in the primary winding should equal weight with the secondary winding or there will be a problem with efficiency. Why not use a half wave bridge? That will reduce the output voltage by a fair bit or use a regulator on the output to give you 50 - 0 - 50 ... or better still a transformer of the correct voltage eg 35 - 0 - 35I have this 800 VA 220 primary, 47-0-47 secondary toroidal transformer. It gives 65-0-65V after the bridge. As I only need 50V can I unwind some coils? It also buzzes a bit, even when at no load. Is there anything I can do to fix this?
Thanks.
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You should be able to remove some of the secondary windings, but the wire thickness and flux desity will limit the current to the same as with the windings on it, just the voltage will be less. It is mildly important to evenly distribute the secondary windings around the core. This may require removing the whole secondary and re-winding it from the start, with thicker magnet wire if you intend to get the same efficiency. You can always paralell smaller windings to equal a larger wire ga.
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While you *may* physically unwind and rewind a toroid by hand without the proper machine, I wouldn't.
**Way** too crude .
Mind you, I *do* wind transformers commercially, have already made and sold thousands ... but with the proper tools, of course.
In Miguel2's case, I would either search for a proper transformer if needed for something already built, *or* build a more powerful amp which was happy with +/- 65V rails .
**Way** too crude .
Mind you, I *do* wind transformers commercially, have already made and sold thousands ... but with the proper tools, of course.
In Miguel2's case, I would either search for a proper transformer if needed for something already built, *or* build a more powerful amp which was happy with +/- 65V rails .
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