Re: idea - wireless distributed home alarm system

You could arrange the logic so that if the one sensor tripped twice
within say one minute, or two different sensors tripped then activate
the alarm. Cheaper than two sensors per room. Also, you can use dual
detection sensors. These use IR and microwave sensors built into one unit,
and both sensors need to trip to activate the output.

David

Yes, that notification point can be a pain - having driven across the city
recently to attend a false alarm. My current thinking is to duplicate the
few sensors I have. ie position 2 at different locations in a room or
hallway so that both would need to be active at the same time to cause an
alarm. Has anyone tried this?

Cheers.

I had thought of this a while ago but using standard home alarm
components, using a code hopping UHF car alarm in the sensors. This
would send a secure signal back to the normal home alarm panel inputs.
Depending on how many ZONES and devices you need, each ZONE would
require a different receiver.
Oatley Electronics have a receiver unit that can accept up to 15
transmitters.

http://www.oatleyelectronics.com/remote.html

This means each ZONE can have up to 15 sensors connected to it.
You would then use the alarm output to trigger the sirens/lights etc,
which could be hard-wired or remote(via another transmitter/receiver).
Throw in the $50- Jaycar Nokia SMS kit and you would have one hell of
a home alarm/notification/automation system...

Just a thought.
             Scott B.

Instead of passive sensors reporting back to an active control
box/panel with a siren, why not a distributed system with each sensor
containing its own siren?

If one sensor is tripped then it sends out a signal and all of the
other sensor locations squeal. There is no one point that can be brute
forced to kill the system; you would need to crack the message sequence
used to command the sensors to arm or disarm.

Maybe this has already been done...?