AVR, Arduino etc. We don’t need sophisticated micro controllers like 8051 to build a very simple burglar alarm circuit with minimal features. So let’s build a burglar alarm using transistor and scr as main components.
;CONSTITUTION: An input signal holding circuit 2 is constituted of a thyristor SCR, the SCR is set up to an ON state by using current flowing at the time of receiving a detection signal from a detection part 3 consisting of a wire or the like as a gate circuit, an alarm 5 is driven...
A burglar alarm switch for protecting a closing member supported on a frame, such as a window, a door, or the like, has a first member which includes terminals adapted to be interconnected within the
3049699Sound actuated detection and alarm system1962-08-14Larrick et al. Primary Examiner: Caldwell, John W. Assistant Examiner: Slobasky, Michael Claims: 1. An intruder deterrent for actuating an illumination means for a selected period of time in response to a sound, said deterrent comprising:...
An automotive burglar alarm system receives an input from a gasoline float responsive potentiometer. The potentiometer is included in a voltage divider with a manually adjustable resistor. The divider