[Milsurplus] Design for a cheap 400Hz power supply

[Richard Brunner]

That occured to me too, with those 40 power transistors.  The waveform looks
like triangles with nicely rounded tops - not a bad approximation of a sine
wave.

Richard Brunner, AA1P

Re:
> I have a similar puppy. This may not be an easy frequency change. It's an
old
> design and, if memory serves, generates the sine as a sum of square waves
> (fundamenal & third harmonic). There could well be power tuned circuits as
> output filters..