This two-tube circuit, one being a double, was found in Radio Electronics magazine from July 1958. The distance to the microphone depends on noise and losses. The cable must be shielded.
This amplifier with high input impedance was suggested by National Semiconductor in its 1994...
This circuit synthesizes the tick of a metronome with the speed controlled in RV1. The circuit is...
This circuit makes use of an unusual component which is a large surface diode that can be used to...