Found in a 90s Popular Electronics, this circuit uses a simple 9 V source. The power can be used from the circuit with which it works.
This circuit is from a Popular Electronics from the 90s. The circuit has a tone frequency...
This solar powered circuit was found in a 1991 documentation. The transistor is a general purpose...
This circuit is based on a common cathode 7-segment display. The circuit is based on CMOS...