EDM PULSE FORMING CIRCUIT ARRANGEMENT AND METHOD

An EDM pulse forming circuit arrangement and method employs an oscillator to produce a succession of quantum signal pulses of a pulse duration .tau.on.q and a pulse interval .tau.off.q. A gating circuit is used to gate the quantum signal pulses and to turn on and off a power switch in circuit between a DC voltage supply and a gap discharge circuit with the gated quantum signal pulses to develop a train of quantum machining voltage pulses across the machining gap within each time period Ton of the gating pulses. The gap discharge circuit incorporates an impedance such that the quantum voltage pulses of an extremely short duration result in a substantially continuous, unitary and pulsed current flow through the gap within the gated time period Ton, constituting an individual machining electrical discharge of a duration .tau.on which is substantially equal to the time period Ton.