This alarm is either activated or triggered after a certain amount of time, giving the owner time to exit or enter and disarm it. The circuit is from a Radio Electronics from April 1975.
We found this circuit in the Linear Applications Handbook by National Semiconductor. The circuit is...
This wide-range radiation monitor was found in a 1980s documentation. The circuit uses a diode as a...
This circuit is from an article that appeared in the June 1974 issue of Radio Electronics...