This stereo meter-indicator was found in the August 1971 issue of Radio Electronics magazine. The transistors are known types and BC548 equivalents can be used.
This is the traditional configuration of an inverter amplifier with operational. The operational...
In the figure we show how to implement a voltage-controlled oscillator. The circuit is from Texas...
Found in a 1967 American publication, this circuit with feedback for two transistors has a gain of...