This circuit was found in a 90s Radio Electronics. It is intended to amplify the sound channel of analog televisions of the time. The integrated circuit used is uncommon today.
The circuit in the figure indicates when the input voltage exceeds a certain value adjusted by the...
We found this circuit in Radio Electronics magazine from May 1962. The circuit uses rectifier...
This circuit, from a 1974 publication, can be assembled with BC548 transistors. If powered with 6 or...