The Turn Of The Century Electrotherapy Museum

Military Quenched Spark Gap Tests
9" Pancake Coil:  500 Turns of 34 AWG wire

This is working well on high power.  Discharge will exceed 12" if sufficiently insulated.

A sidewards view showing the gap.  Note there is no light from the gap as they are enclosed in the washer sections.

Frank sent this Quenched Gap that contains a combination of two companies disks - one that is silver plated copper disks which
have been formed to the desired shape, and a second type that is tungsten soldered to brass machined disks.

This gaps are based on the Lepel and Telefunken patents, the original Quenched Gap being patented by Kinraide in 1899 6 years earlier.

The discs are made with a recess to accept an insulating washer.  Without the recess the arc occurs at the edges of the washer instead
of the face of the disk.  Here I am using filtration paper.