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Old June 22nd 09, 12:36 PM posted to rec.radio.amateur.homebrew
JC Morrice JC Morrice is offline
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First recorded activity by RadioBanter: Aug 2008
Posts: 6
Default Other uses for Microwave oven transformers?

In article
s.com, terry writes

Trying to clear out some 'junk' but have always tended to keep
scrapped parts from old (UNREPAIRABLE/NOT-WORTH-FIXING) microwaves!

e.g. the transformers, fans, fuse holders, overheat switches. And even
occasionally have used some of them for repairs to other microwaves!

I applied 115.7 volts AC to what had been the HV winding of one of
these scrapped transf. recently and got about 6 volts on what had been
the original primary. That established the ratio between the two
windings as approx 20:1.

Also a small voltage (about 0.185 volts) across what had been the
magnetron (Approx. 3 volt?) heater winding. Which gives ratio of about
1:33 to the original primary winding; also a ratio of about 1:700 from
the original HV winding.

So the idea of using the transformer backwards comes to mind????

snip.......

Depending on the unit they are typically rated as follows?
This is all supposition at this stage! Any comments criticism????

Seems there are quite a few uses for them!

Other uses:

good:
http://www.rhunt.f9.co.uk/Electronic...lder_Page1.htm


Neat, but not so good - has he never heard of screening mains supplies?:
http://www.youtube.com/watch?v=Wp7JF2sANsw


Sheesh - doing this over large metal sheets with live mains involved an
apparently zero mains insulation / isolation box / separation. Would
*LOVE* to see his kilowatt linear; but perhaps not:
http://www.instructables.com/id/Buil...rmer-Homemade-
Welder/

John
--
JC Morrice