This balance indicator for stereo amplifiers was found in an 80's Elektor. The components used are common. Zeners are 1.8 V or close to that value.
This circuit was obtained in a 1967 Raytheon manual. The company's component is an optical coupler with...
Powering from a 36 V supply this circuit has a power output of 16 W in 4 ohm loads. With 40 V and...
This circuit has very high input impedance and a differential input. The gain is 1,000 and the...