This circuit was found in a 1966 General Electric documentation. It makes use of direct contact water sensors and therefore requires an isolation or low voltage relay drive transformer.
The circuit shown was found in the 1994 National Semiconductor Linear Applications Handbook. The...
We found this circuit in a documentation for radio amateurs from 1975. The FET can be the BF245 and...
This circuit is from an old documentation making use of a 3,579,645 MHz analog color television...