The Turn Of The Century Electrotherapy Museum

New design for an Induction Coil
based on a Radio Inductance Coil

15 Turn Primary Coil, 750 Turn Radio Inductance Coil (Tuning Coil from De Forrest and similar sets)

Core is 1.375" x 5.500" long

Whole assembly tossed in wax for insulation

Produces 12,000V in the circuit below

Sparks 1/2" - 3/4", believed to be around 25kHz

Tesla Coil Circuit, yet unusual values for low frequencies