We found this circuit in a 1965 publication by General Electric. The zener is 8.2 V x 1 W and the table shows the capacitor values according to the number of cylinders in the vehicle.
This circuit was found in an English publication from 1989. The integrated circuit is an...
This circuit was obtained from a 1964 magazine and has some interesting features such as the input...
Using a general-purpose transistor this AC amplifier was found in the November 1993 issue of...