To hot wire the farm, you will need to get up in the 500-600v range@25uf before you dump it into the transformer.
It is best to use a much higher turns L1 and use about 4uf across the transformer primary, this will shape the waveform much better for transmission, and noise, and shock in the output scr or triacs.
I make simpler more powerful units that have hit over 40amps@8000volts ( thats a lot of watts ). They use 1 transistor, and 5 triacs and not much else. They have run for the last 7 years at least.
The trick to making the power transformer is to use something big for a start.. I use microwave transformers.
Slit the thing apart, get rid of all the windings, we only want the laminates.
Make a former ( I use wood).... For the primary, about 18 turns of 1.2mm or more 2 in hand to take up the width of the former.
For the secondary, about 230 turns.
1. Isolate the primary with transformer paper .
2. wind the first layer of 1 turn thick of secondary.. maybe 40 turns side by side, no overlapping... very neat.
3. put a layer of transformer paper over that, then wind the second 40 turns or whatever fits for each single layer.
4. Make sure you are about 3mm back from the edge of the paper with each tidy layer. This makes it very very hard to jump, as the spark has to get past the 3mm, then back in op the layer under or over it for another 3mm.... wont happen, even with 13000v they don't compromise.
5.When you have your 5 or 6 layers done, more transfromer paper on top, then tape it up.
6. Get some epoxy or lacquer and lacquer it. I use epoxy.....
7. Use more transformer paper in the E slots, and place the winding on the transformer laminates core. You want there to be transformer paper stopping arcing where ever there is an opportunity.
8. Re-weld transformer and your done. This should last forever if you do it neatly, and with purpose. I have not seen it arc.... ever, and thats testing to over 14000v.... there are quite a few out in the field, and our moist marine environment would show up the weakness very quickly.
..........oztules