摘要:
A starting impulse generated when the crank shaft of an engine passes a specific point and starts a counter that counts impulses for one revolution. During the same revolution, another signal corresponding to a specific engine event starts another counter that continues until the end of the same revolution. A computing circuit uses data from the counters to determine engine speed and the angle at which the engine event occurs and presents this information as a numerical readout. A mark signal may be generated as a cursor for cathode ray tube display of ignition or other engine waveforms. The cursor can be moved to any point along the waveform by a manual control, and the angle at whatever point is selected will be presented in the numerical readout.