This circuit is from an American 80's documentation. The integrated circuit is from the time and the sensor consists of a smoke chamber measuring its transparency change.
The circuit is from an 80's publication, but the components are current, only special type diodes...
This circuit was found in a 1965 Electronic Design. Transistor Q2 must be load dependent. The circuit...
This circuit was obtained from an 80's amateur radio documentation. The integrated circuit is a...