The Turn Of The Century Electrotherapy Museum

 4" Capacity Induction Apparatus...

...Powering a Tesla Coil!

4" Induction Apparatus operating on its own.

A series spark gap is now placed in parallel with the induction coil output, and a Tesla Coil with a condenser in series is then added.

The Tesla / Oudin Coil is wound on a 2.375" OD form - 25 turns of 18 AWG wire and 750 turns of 34 AWG.  The secondary
winding  is only 5" tall.

Produces a discharge 4" or so in length.

Though this induction coil will spark 4", when a condenser circuit it can only be used to charge smaller condenser - .002 mfd is
used for these tests.