The Turn Of The Century Electrotherapy Museum
(C) Jeff Behary 2010 

Derek's Spark Gap
Here is a 4-series adjustable gap I made for Derek, who wanted something
suitable for neon transformers and potential transformers.  It uses 3/8" diameter tungsten.

This gap occupies a space of only 6.75" x 3.5" x 2".

(C) Jeff Behary, 2010