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 operates at the frequency of a small transmitter up to 27 MHz, triggering a relay from...
This medium wave radio with 7 germanium transistors was manufactured in Japan in the 1960s. Its...
In the figure we have the way to implement a power zener diode. The voltage depends on the zener,...