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Arfa Daily Arfa Daily is offline
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Default microwave transformers


"mike" wrote in message
news:aae6i.1985$XC3.1557@trnddc04...
Arfa Daily wrote:
"Charles" wrote in message
...
"geoff smith" wrote in message
news Can anyone suggest an interesting use for microwave oven transformers .
Regards Geoff.
Ham radio enthusiasts use them in power supplies for high-power vacuum
tube transmitters.

Although they're not actually terribly good for this use, as their design
makes them self-limiting by way of core saturation, as I understand it.

Arfa

Core saturation blows fuses. Don't think that's the mechanism going on
here. But there are magnetic shunts that increase the leakage inductance
and limit current. Take out the shunts for non-limited
applications.
mike

That's probably right. I was going to use one for obtaining the HT supply
for a 3CX400 I think it was, that I used in a grounded grid linear for 2
metres some years back, but in the end I didn't after reading a very
detailed article on why they were no good for the job. As I say, it's been
some years now, and the presence of magnetic shunts may well be the main
reason quoted - I don't remember for sure. But something about the core size
or it's characteristics or something seems to keep coming to mind as being
the quoted reason for the secondary regulation being very poor when the
current demand is variable, as it would be when powering an amplifier being
driven with an SSB exciter, as opposed to it's designed use of providing the
HT for a magnetron power oscillator, whose current demand will be pretty
much constant. Maybe that situation has changed now, with the recent
introduction of true power-controlled microwave ovens, rather than the
former on-off switching control to produce an average cooking power ?? Maybe
the trannies from this generation of ovens are better suited to
'alternative' uses ?

Arfa