A Transistor Based - Single Zone Alarm
This circuit features automatic Exit and Entry delays - timed Bell/Siren cut-off - and system reset. It has provision for normally-open and normally-closed switches - and will suit all of the usual input devices (Pressure Mats, Magnetic Reed Contacts, Foil Tape, PIRs and Inertia Sensors).
   A Transistor Based - Single Zone Alarm
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