This electronic rheostat with SCR was found in the June 1964 Radio Electronics magazine. The SCR may be a modern type and the 2W potentiometer may be 470 ohms.
The more sensitive the instrument used the better the sensitivity of the indicated meter. We...
Based on the 4017 integrated circuit, this circuit of a European 303 Circuits from the 90s,...
The integrated circuit used in this project is unusual and it includes internal transistors that...