This circuit lets through the 300 Hz to 3kHz range that corresponds to the human voice. We found it in the Radio Electronics magazine of February 1990. The circuit uses both parts of the LM381.
This power supply was found in a 2000 documentation. It can supply currents from 2 A to 15 V and 1...
We found this circuit in a Radio & Electronics Constructor of November 1975. The magazine no...
This circuit is designed to modulate small AM transmitters with the same power order. The circuit is...