Suggested by a 90’s Radio Electronics, this circuit automatically activates the recording switch of an old tape recorder. It can be adapted for other purposes.
This circuit was found in the 1972 RCA Power Transistor Databook. Transistors are uncommon today,...
This circuit is used to light a 20 W fluorescent lamp from the 12 V of a car battery. The...
This circuit fires by burning the fuse when the input voltage exceeds the value referenced by the zener....