This simple rain, leak or moisture detector circuit appears in other places on this site with slight variations. This was obtained in an English documentation from the 70s.
The maximum frequency of the oscillator shown in the figure is around 3 MHz. The trimmer adjusts the...
This circuit was obtained in a 1977 Radio Handbook. The transistor is from the era and the coils...
August 2017 - STMicroelectronics' BlueCoin development environment is available at Mouser...