6 V x 5 mA regulator (CB21537E)

This 6V regulator with FET was found in an old Electronic Design. FET and transistor admit modern equivalents.

Micro FM Stereo Integrated (CB25238E)
Using a BA1404 integrated circuit this small FM stereo transmitter was found in a Radio...
Tremolo Amplifier (CB19609E)
The operational amplifier is not very common today, but in its place an equivalent, even of...
Semi-isolated Collpits oscillator with parallel crystal (CB25555E)
This circuit was found in the February 1993 Radio Electronics magazine. The frequency depends on...