Easy-auto-alarm


Posted on Sep 25, 2012

See (a) for the timing information for the alarm circuit in (b). When leaving your vehicle, flip the arming switch and close the door to arm the device. Subsequent opening of an entrance triggers both timers. After the expiration of the entry delay timer, the alarm sounds for a time determined by the second timer. The value of R should be less than 1 KO. If you use an incandescent lamp instead of a resistor, you get an extra function-an open-entrance indicator.


Easy-auto-alarm
Click here to download the full size of the above Circuit.

By keeping the resistance low, you avoid false tripping should water collect under the hood. If your door switch connects the courtesy light to 12 V rather than ground, use a single transistor as an inverter at the input.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Lego Double Rotation Sensor
Voltage detector relay
Auto Ignition Cut-Off
Plate Touch Sensor Circuit
BEAM Sonic
Circuit Compact DJ Station
Noise Floor Measurement Circuit of PLL Frequency Synthesizers
Audio
160 METER VFO
Dance hall circuit automatically fill light
ISO122 124 filter circuit diagram
1880MHz internal bias circuit diagram of the amplifier application collector RF2324



Top