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.
This circuit was obtained in a magazine for radio amateurs 73 of the 90s. The circuit is based on...
This input stage has unit gain but a high input impedance and low output impedance. The circuit is...
May 2016 - It can be obtained from Mouser Electronics new display 1092 from VDC. The new LED...