This circuit uses a diode as a radiation sensor. The operational ones are old because the publication is from the 80's, but modern low voltage equivalents can be tested.
This circuit, from an old ON Semiconductor publication, suggests a shield to excite an LED from an...
This circuit was obtained from an old American documentation having a limited adjustment range....
Microchip Continues Expansion of AVR Microcontroller Product Line with Addition of Three New...