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.
Using the XR2208 integrated circuit, we found this application in the Radio Electronics magazine of...
This circuit was obtained from Signetics documentation from the 80's. The components used are from...
This circuit consists of a switched mixer with digital touch control. The circuit was found in old...