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.
This circuit is from a Mallory 1968’s documentation. The integrated circuit is of the time and the...
For those who like experimental circuits, here is a sequential flasher system with LEDs, which can be...
This circuit was found in an English publication in 1986, but it can still be implemented by...