This audio amplifier circuit was found in Radio Electronics magazine from June 1966. The circuit is a commercial RCA type and is powered by mains power.
In this circuit the LED lights up when the voltage drops below the value set in the trimpot. The...
This circuit was obtained from a Linear Technology manual from the 90's. The integrated circuits are...
Found in a 1995 documentation, this circuit is an alternative output to the previous circuits. The MOSFETs...