The transistors of this circuit found in a 1965 magazine can be the BC558 and the sensitive 12 V x 50 mA relay. The other components are common.
This circuit was found in a 1987 magazine. It generates signals in a range from 100 kHz to 10 MHz,...
This circuit was obtained from an Electronic Design from 1964. Transistors admit modern...
This circuit can generate audio signals at frequencies ranging from 0.01 Hz to approximately 20...