This circuit allows you to adjust the balance between channels of a stereo amplifier. The circuit makes use of an analog indicator with zero in the center of the scale.
This circuit from an old documentation uses an optocoupler to control the feedback. FET is...
We found this circuit in a publication for radio amateurs in 1974. The bipolar transistors can be...
This circuit was found in a documentation for radio amateurs from the 70s. The integrated circuits...