Window pane alarm unit e.g. for when glass is totally or just partially opened or penetrated, has disk thermally attached to surface of glass with outside of disk having primary antenna arranged and inside of disk

摘要

The unit has a disk (2) thermally attached to the surface of the glass. Outside of the disk a primary antenna (22) is arranged and inside (16) of the disk a secondary antenna is arranged. Enquiry signals are passed to the primary antenna and to a receiving antenna if there is no break on the thermal link. An independent claim is included for a system, and a method.