This alarm circuit with NC sensors in series was taken from an article in Radio Electronics magazine from May 1971. The SCR can be any of the 106 series.
We found this circuit in a 2005 documentation. The circuit allows the automation of a gate through...
Found in an 90s Electronic Design, this circuit provides a 110 dB output to a ceramic transducer....
This circuit activates a relay with a frequency signal determined by the adjustment components. The...