With this circuit it is possible to modulate pulses from a pulsating input signal. The PNP transistor can be the BC558 and the power must be supplied with 5 V.
This circuit is from a 1987 American publication called Electronics Handbook. The circuit can be...
The indicated circuit performs a slow charge of 12 V batteries maintaining a constant current of...
This ultra-simple circuit need a carbon microphone to operate. The circuit must be powered from D...