SELF-POWERED TACHOMETER CIRCUIT
Original Publication Date: 1983-Mar-01
Included in the Prior Art Database: 2001-Oct-10
A tachometer circuit which derives its power from the signal it is monitoring is shown below. It is particularly suited for measuring engine velocity and acceleration, but may be used to monitor and filter noisy, repetitious waveforms so that the signal switching frequency may be determined accurate- ly. In normal use it may be connected to the primary side of an automobile ignition coil which is being controlled electronically or mechanically.