SGG — "modulator"
both spark gaps running on one primary, seems secondary does respond to modulation, not as I expected though…
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For the term "hho modulator sematrackback".
PWM High Voltage Spark Generator
This is a simple pulse width modulator circuit connected to a car ignition coil. It produces high voltage purple arcs and its a screamer. Oh— and it also lights up a modified CFL.