This circuit is from the time when cars used contact breakers. This 80's version measures the dwell angle of the contact breaker for dwell adjustment using an era integrated circuit, the LM3917.
The circuit is from a June 1995 Electronics Now. The relay is power-dependent and both R1 and R2...
This circuit for several frequencies was obtained in an American documentation from the 90s. The...
The circuit shown in the figure is suggested by AllegroMicro (www.allegromicro.com) and consists of an...