This circuit was found in the February 1993 issue of Radio Electronics magazine. Some components depend on the crystal frequency and can be changed.
Critical components of this project are the Geiger tube and the 300V battery. The battery can be...
Using the four amplifiers of an LM324 this circuit was found in the June 1996 issue of Electronics Now...
This circuit was found in a Popular Electronics from the 90s. Transistors admit equivalents, as well as...