We found this circuit in a 1967’s Electronics World. The circuit can be made with modern equivalent transistors. The selection is made by the tuned coil.
This high-gain circuit uses junction FETs (JFETs) and must be powered by somewhat high voltages. The...
This circuit counts 1 per second, displaying the value in binary. The circuit is TTL and must be...
Critical components of this project are the Geiger tube and the 300V battery. The battery can be...