Operated directly from the power grid, this detector was found in an 80's RCA documentation. The sensor is an ionization chamber. The SCR triggers a warning siren.
This circuit was found in the March 1990 issue of Radio Electronics magazine. The circuit can be...
Found in a 1980s English magazine, this trigger circuit can have different types of inputs...
We find this circuit in an American manual from the 80's. The circuit can be implemented with more...