A third PCB-etched coil, arrived at independently of the two elsewhere on this tree, with its own electronics. A half-bridge of IRFP260 MOSFETs runs through a UCC37322 driver, fed a clean square wave by an SN74HC14N Schmitt trigger that reads the resonant feedback straight off the secondary. The power supply is the unusual part. An onboard boost converter, a UC3843-controlled stage, steps 12 V up to an adjustable 33-65 V bus for the bridge, so no external high-voltage brick is needed. An LM358 mixes stereo left/right audio into the interrupter path, and a second NE555 and an LM393 comparator shape the drive for music mode. Control is over Bluetooth, not USB-MIDI or a 3.5 mm jack. Both a real photo and the full schematic were checked directly, beyond the project summary.
Schematics and photos
full schematic: UC3843 boost stage, UCC37322 half bridge, audio + interrupter
Sources
This is the card from the driver tree, written from what the builder published. Send corrections through the forum.