Description

Fig. 1 Electronic Ignition system schematic.:

The electronic ignition system, Fig. 1, consists of an engine driven ignition distributor which includes a trigger wheel, pulse generator and conventional centrifugal and vacuum advance mechanisms, and a remote mounted ignition coil and amplifier assembly. The trigger wheel is mounted on the distributor shaft, and the pulse generator is mounted on a plate controlled by the vacuum advance capsule. As the vanes of the magnetized trigger wheel rotate past the pole piece of the pulse generator, alternating current pulses are induced, and these pulses are transmitted to the ignition amplifier. The construction and timing of the trigger wheel causes these voltage pulses to be induced in time with the engine compression cycles.

The ignition amplifier controls coil saturation and primary current switching based on voltage signals transmitted from the pulse generator. When voltage signals from the pulse generator change polarity, the amplifier opens and closes the coil primary circuit, causing secondary spark voltage to be induced in the coil windings. The polarity of the pulse generator signals changes when the vanes of the trigger wheel pass directly over the pulse generator pole piece. This allows ignition timing to be controlled by centrifugal and vacuum advance mechanisms by altering the phase relationship between the trigger wheel vanes and the pulse generator pole piece.