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Old November 25th 04, 05:59 PM
Ian White, G3SEK
Posts: n/a

Tim Wescott wrote:
Alan Horowitz wrote:

John Popelish wrote

Microwave oven transformers operate with parts of the core very
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)