Technical mounting alarm sensors

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Technical mounting alarm sensors

kajl

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hi all again,

those of you that fitted an after market alarm, where did you place the shock sensor and ultrasonic sensors? because in my case ...

1) ... I've set the shock sensor to maximum sensitivity, and while holding it in hands, it is very sensitive (as expected) to very light impacts; meaning the sensor is 100% working. However, with the sensor placed under the dash (driver side, where the fuses are placed) I really have to hit the car very very hard on the windshield to trigger the alarm. If I knock the car from the back or any other door, the sensor does not detect the impact...

2) whats the best position possible to place the ultrasonic sensors in a way that they detect whoever gets too close to the car? At the moment they are placed exactly where the A pillar ends (top end)...one on each side, and are set to full.

thanks all
 
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ultrasonics won't detect people outside the car or they shouldn't if they are set right, ultrasonics have a tx and rx basically the way to set them is one on pass side door pillar and one on drivers side door pillar at top ot plastic trim, aim them towards the center of the rear screen. that shock sensor will cause you nothing but misery, set it too high and the wind or a car/lorry/bus will set it off, you could go 2 zone microwave but unless your used to alarms they are a pain in the ass to set up, also it's possibly not wise to have outside sensors that trigger alarm if someone gets too close to the car as you will get so many false triggers that no one will take any notice if you get a real trigger.

i would get either a set of ultrasonics for inside and maybe a glass break sensor or antijack sensor (to protect wheels, triggers if the car is jacked up past a set degree) other option is infrasonic this works by comparing outside air pressure with inside air pressure, only porblem being slightest difference like airvents open or window open slightly and it will trigger.

like i say good immobilizer spliced into the wiring loom at about 4 different places and behind 1 or two panels that need to be removed with screw driver( behind fuese box and along door sills is a good place to pick up for immobilizer cuts) and a set of well positioned and well secured ultrasonics should be ok.
 
the ultrasonics are set up exactly how you described, and do not set off the alarm if someone walks close to the car. I thought I could make them more sensitive to the outside of the car.

regarding the shock sensor, even if I hit the car very very hard near the side where it is placed, it doesn't detect the impact even though it is set to full :/

like I said, if held in hands the shock sensor is very sensitive so i guess its working fine. besides, im using a thin piece of double sided tape (not a velcro or thick foamy tape).

does it make a difference if it is mounted horizontally or vertically? atm it is vertical with the inner side of the dashboard
 
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