We found this circuit in a technical documentation for the National Semiconductor LM3909. The circuit consists of a low consumption continuity tester powered by a single battery.
This simple circuit was found in an English magazine that no longer exists, January 1970 issue. It is...
This circuit, suggested by a 1975 documentation, detects an electrical discharge in a storm by...
This circuit for timing small loads was found in a 1964 General Electric documentation....