[Open_electroporator] Culture Shock yardboard testing

[John Griessen]

The transistor I grabbed is not cutting off with a zero volt input from the pulse generator.
That's where I marked 270 mA on the photo.

That explains the big ringing on the middle waveform, the output of the transformer.  the input volts aren't
forced to a hard diode drop, they bounce back once then waver and some current is still going through the FET transistor!
I'll try a very different bipolar I have that will need few changes to the circuit.

The doubler does give the opposite polarity I thought it would, so I'll take that apart and analyze some.
It was putting out smooth DC at 700V When the switcher DC input was 7.5V.

Goal for evening is somehow figure a good spec for quoting to a China transformer winder.
I definitely will be asking for a 3kV all in one transformer quote to compare and see if they say it is workable...

It's not good to try to fit HV in too small a space, since it jumps air gaps.  10 kV jumps 1/4 inch, 6.3mm,
so 3 kV jumps 1.9mm just being there.  A 3 kV transformer would need to have its windings in slots on the bobbin
so a fraction of the turns is in one slot, then 2mm over some more, and repeat.  The little transformers
with 11mm cores can have one slot for input, and 3 for HV so they might work...
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