Dual Tech Interaction

Yes.

You can, but you must adhere to the installation instructions.

The question is: How big is the room?? What do you need to protect in it that you can't do with a system that's geared for perimeter? Space protection (IMO at least) should always be considered the "back-up" to a good perimeter system.

The next quesiton is: Why do you need dual technology sensors?? Have a look at the Paradox series of digital infra-red detectors. They're rock solid.

Can you not get sensors on different frequencies as in the UK. The one we use is available in three different frequencies.

Many years ago when single technology microwave detectors were in common use you had to avoid placing one detector within range of another. ISTR there were some that could be set at different frequencies but I rarely used more than one uWave in the same house. Ultrasonics were much more trouble than uWaves.

These days most detectors that use microwave are fairly safe to use in proximity to one another.

Sorry, no, the only frequency we can get happens to be the same freq as Paul's wireless headphones, making them totally useless for detection.

Plenty of signal coming out but no notice being taken of the incoming signal. !