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Old July 22nd 06, 12:50 AM posted to rec.radio.amateur.homebrew
Tim Wescott Tim Wescott is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 202
Default Microwave oven transformers

AndyS wrote:
Andy writes:

I have been thinking about building a high voltage power supply
for a big amp, and am toying with the idea of using a couple of
microwave oven transformers, which I have on hand.

I plan to use two, with the primaries connected in parallel but
opposing, so that each one will supply voltage, half-wave, to a
diode ring. By doing this, I can have each core grounded like it
is used in the ovens....

So, has anyone else done this and run into any problems that
I may not have forseen ?

Using 1/2 wave rectification on each one will result in big DC currents
in the coils. These DC currents will saturate your cores like nothing else.

If you wanted to do this and be safe you'd want to rewind the primaries
after insulating the core with some appropriate high-dielectric strength
material like Kapton.

If you're in the US you may want to consider using the primaries in
series, and running off of 220V.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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