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 sensors in this circuit, found in a 1999 documentation, are stripped wire tips at different levels...
This traditional crystal oscillator configuration can use any CMOS gate configured as an inverter. R1...
This amplification stage circuit with a germanium transistor was found in a 1980s documentation. The...