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Old July 22nd 09, 01:36 AM posted to rec.radio.amateur.homebrew
stan stan is offline
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First recorded activity by RadioBanter: Mar 2009
Posts: 18
Default Use old microwave cabinets?

On Jul 18, 6:57*pm, brian whatcott wrote:
JIMMIE wrote:
On Jul 15, 10:52 pm, stan wrote:
On Jul 13, 1:02 am, raypsi wrote:


Hey OM:
Microwave ovens are built for a price, the cheaper the better. The
Chinese have a lot of crap out there. Even the fans are junk. I mean
who uses a shaded pole syncro motor for a fan these days, power hungry
junk. Best you could get out of a microwave oven is the metal cabinet
can be cut up with scissors, that's right, dollar store scissors, will
cut the sheet metal they use on microwave ovens. And with a good brake
you can make a lot of project boxes.
Well stainless steel project boxes would look sweet.
73 OM
de n8zu
Yup somebody gave me a stainless four section container which appears
to be unused and from an old fashioned ice-cream parlour/soda
fountain. There is also a single container, same depth and height etc.
And there is a nice rim around the open ends to which a front panel
could fastened!
Immediately thought of ready-made small equipment cabinets!
Scrapping a bunch of old microwaves is what raised the question of a
reuse for the cabinets. We had a school cafeteria operation one time
with three or four m.waves in use for short periods, on several
occasions was able to scrap older ones for parts for repairs. Now just
junk lying around!


I saw one at a hamfest in the tailgate section someone was trying to
sell that was turned into a HV power supply and it used a pair of
microwave oven transformers.


Jimmie


Instead *of the 1 KV power supply at 1 Amp, there's the possibility of
bandsawing off the high voltage winding all together, and winding on 5
or 6 turns of welding cable. * This makes a useful spot welder for
stainless steel sheet, which material performs specially well with spot
welds.
The power is low end so its important to choose a microwave rated at
least 1100 watts for this makeover.

Brian W- Hide quoted text -

- Show quoted text -


Same technique (cutting off HV winding and putting a few turns to make
a battery charger transformer was also mentioned.
And previously had mentioned that HV winding to 115 volt mains winding
was a turns/voltage ratio of approx 20:1.
Hence an impedance matching ratio of 400 to one! Might be good enough
to match an 8 ohm speaker load into say a triode connected power tube?
400 x 8 = 3200? Haven't tried it! Just rambling around. Hate to throw
stuff away.