PWM Audio for PI Metal Detectors

[Vadim18]

PCB + KiCad Schematic PWM_Audio.zip


Circuit for clarity.
C4 (2.2n) must be film type Kemet, Epcos, Wima, all other - disc type ceramic, especialy C3.
Gnd and 12V terminals must be wired directly to main capacitor leads (biggest capacitor) on Surfmaster PCB.

[bernte_one]

@Vadim18 THX

[Vadim18]

Welcome to the world of alternatives, here is another option of PWM audio for pulse m.d.


ic - any CMOS inverter with Schmitt trigger