This 40-second delay switch was found in a 1965 Electronic Design. The unijunction transistor might be the 2N2646 and the SCR a sensitive modern equivalent.
This simple telephone amplifier can be used as an auxiliary amplifier for additional listening, without...
This circuit can be used in fiber optic links or even direct links to microcontrollers and other...
This article was obtained in a French magazine Nouvelle Electronique from 1994. It can be easily...