4-Quadrant Multiplier (CB24753E)

Found in July 1983 Radio Electronics magazine, this circuit uses a transconductance operational amplifier. The power supply must be symmetrical.

Up to 10 MHz Oscillator using Transistors (CB9416E)
This circuit, from a 1973 documentation, can be made with BC549 transistors. The frequency depends on...
Control for miniature railway (CB7085E)
Suggested by General Electric in a 1965 documentation, this circuit can use the TIC106 as an SCR....
Voltage Calibrator (CB21331E)
This circuit is from an old Popular Electronics. The circuit is based on a 555 and a 5V voltage...