This interesting multi-channel circuit was found in the August 1988 issue of Radio Electronics magazine. It monitors the signal from 4 sound channels simultaneously.
This circuit can be powered by 2 or 3 small batteries. The resistor can have values between 220...
This circuit shows how to use a fixed 5 V regulator on a variable 1 A source. The integrated...
This circuit generates an FM signal of 4.7 or 10.7 MHz for audio signals on analog TV or FM, with...