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 Cross Fader as it is also known causes the brightness of one lamp to increase while the...
This circuit will trigger a buzzer with an oscillator if the ignition key is removed with the...
This circuit was obtained from a 2005 Linear Technology application manual. The circuit is...