I finally got his working! This is a small SSTC with a very simple antenna feedback driver made from one 7400, a MOSFET driver IC and a single IRF840 MOSFET, but it's powered by a ramped power supply running in sync with the interrupter. Over the course of a few milliseconds from the moment a small spark breaks out, the bus voltage is increased to about 3 times the supply voltage.
This demo was done with 40V supply, drawing less than 1A. A faster beat rate and somewhat brighter sparks of longer duration should be possible with a better supply than the small 30V 35VA transformer I used in this video. Everything runs cool, and none of the components appear stressed.
Using a full bridge should make this little coil break a spark at lower voltages and make it more battery friendly. I want to try that next.
