On 27 May, 16:48, "Arfa Daily" wrote:

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

The magnetic shunt means the output is effectively in series with
inductance, which does regulation no favours. But I gather that can be
removed somehow.

A bigger problem is the fact that theyre rated for max 15 minutes use
with forced air cooling - no fan and they fry quicker. 2 in series
should solve that.

The output being connected to the core means fun mounting them too.

NT