This wide-range radiation monitor was found in a 1980s documentation. The circuit uses a diode as a sensor and is quite critical requiring shielding shown in dashes to prevent snoring due to gain.
We found this circuit in an old Italian publication, but it can be fitted with BC558 transistors if the...
This LED indicator circuit uses an LM339 comparator. The circuit was found in the January 1995...
One touch of the sensor and the LEDs run. When you take your finger off the sensor, only one will...