Wireless presence detector. Any thoughts please?

[Nick]

I'm trying to cobble together a wireless presence detection system between rooms in two buildings 25m apart. Line of sight is good. Cabling or wiring is not an option. Ideally mains powered but not essential. The transmitting end needs to be 360deg sensor. The receiving end ideally should have facilities for both visual (a light?) and audible (a sounder of some kind) alert. I know Steinel make kit that would do the job but it is hideously expensive. Visonic MCR 304 and Disc MCW might do the job, but I don't know if these two are able to speak to each other independant of an alarm system.

Any ideas please. Nick.

[Capitol]

Start from 2 wireless pirs?

[newshound]

I was going to say three.

[Capitol]

I was thinking of corner mounted.

[Peter Andrews]

This might help:

I use an LM RX400 linked to an alarm and a couple of LM TX500/15 to monitor the interiors of a couple of out buildings about 20m from the main building. The PIR slave units use a 9v battery- seem to last at least two years.

Peter

[newshound]

Good point!