Hi
David,
What would you recommend for a supply voltage with 500v FET's
in your Quarter Kilowatt linear amp
design?
Mike
WE0H
WD2XGI
Hi Mike.
I converted my version of the 250W linear to class D by fitting a 4013 chip
and the TC4426 FET driver etc from the other class D circuit. I used the
IRFP450.
With no other changes it gave 600 W out from a 48V supply and had
some spare capacity for those moments when you really want the QSO (about 700W
CW on 56V)
I would have thought 60V was the max safe limit. An oscillosope on the
drains will be enough to shock you into not going beyond that (it was for
me)
Also used the same amp for a 500km QSO on 73kHz from Scotland. It clicked
and fizzed like crazy on that band, but held up OK
73
David G0MRF
