Found in a Popular Electronics from the 90s, this circuit presents the difficulty of obtaining the Geiger Tube. The other components are common, admitting equivalents.
To use the instrument for AC measurement, the tips are A and B. For CC use tips A or B for...
The interesting circuit shown in the figure, can have its gain digitally controlled and present two...
This simple MW radio was found in a 1975 publication, but it can be mounted with BC548...