This circuit can be used as an answering password system in a store, office, or other location. The circuit is from Intersil using components of the time. The circuit is from the 80's.
This circuit was obtained from the 1976 Siemens Integrated Circuits Manual. It is the circuit for...
The circuit is a multivibrator version using two NPN general purpose transistor. This circuit can...
The sensor of this circuit is a thermistor of the same value as the adjustment circuit formed by...