This circuit was found in an American 1980s documentation. It analyzes the exhaust gas of a vehicle using a special sensor. The indicator is a milliamperimeter.
The purpose of this circuit is to trigger an oscillator with the light of dawn. The tone of the...
This two-input limit detector was found in an American 1980s documentation. The circuit can be...
This circuit was obtained from a 1970s RCA. The circuit uses LDRs as sensors. The resistors depend on the...