MMC Tank Capacitor

The 4 inch coil uses a 15nF capacitor.  This is considered an LTR (larger than resonant)

capacitor for this design.  It is made up of ten 15MFD, 2000V high voltage, snubber capacitors

in series.  A 10M 1/2 watt carbon film resistor is across each capacitor.

The capacitors are available here through Richardson Electronics.