Triggered Spark Gap

Utilizes a trigger "halo" through which the main arc passes and thus eliminates the undesired
heating and erosion of a central trigger electrode.
Halo conceived by Terry Fritz, carbide electrode faces courtesy of Marc Metlicka.

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Synchronous Trigger Driver

Provides mains synchronized, variable delay drive to a GM HEI coil in much the same manner as in an automotive application.
Unlike the "lamp dimmer" driver which attempts to force the production of a trigger spark upon application of current
to the ignition coil and fails to utilize the "flyback" effect, this circuit replicates the horizontal output stage of a monitor.
The result yields very low jitter along with a maximum delay well into the LTR operating range.