We found this circuit in a documentation from the 70s. The circuit uses amplifiers from the time, but it can be implemented with modern equivalents.
Found in a 1968 US publication, this circuit is designed to measure very weak signals. The...
The sensor can be made using two bare wire or two screen with a piece of tisse between them. One...
This circuit serves as a binary demonstrator using 3 LEDs. The circuit can be scaled up for a...