Found in a 1967 American publication, this circuit with feedback for two transistors has a gain of 20 times. Phototransistors are types of the time.
This inverter can reach a power of 300 W depending on the transformer used. In this case, a...
This circuit causes an instrument needle to oscillate to signal an event. The circuit is powered by...
This circuit converts signals from the 350 kHz to 500 kHz longwave (VLF) band to the 4.35 to 4.6...