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Old November 25th 04, 05:59 PM
Ian White, G3SEK
 
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Tim Wescott wrote:
Alan Horowitz wrote:

John Popelish wrote

Microwave oven transformers operate with parts of the core very
nearly
saturated during parts of the cycle [...]

why are they designed that way?


Probably to save money on the core -- the oven will cost a few cents
less to make, a few dollars less to buy, then you pay that all back to
the power company as your kitchen gets hot. It would also add a
modicum of voltage regulation to the thing, but I doubt that's the reason.

It is mostly done for current limiting, which a magnetron needs because
(in DC terms) it looks like a diode connected across the power supply.
Saving size, cost and weight is also important, so the transformers are
pared right down to the bone.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek