This circuit is a four-quadrant multiplier using an LM3900. The circuit was found in the July 1988 Radio Electronics magazine.
The basic purpose of this circuit is to apply an audio signal to a video carrier for sound and...
Found in a 73 magazine for radio amateurs of the 1980s, this circuit uses a dual-gate MOSFET. This...
We found this Vox in a 1969 Motorola documentation. Transistors support modern equivalents and the SCR can...