Mobile telephone based remote alarm system having memory memorizing expected signals and where signals received different alarm signal raised, remote telephone call procedure raised.

摘要

The alarm unit (1) is a mobile telephone detecting an event and converting the event to a detected digital signal. A call is then sent to a distant telephone (16). The alarm forms part of the mobile telephone and has a memory memorizing awaited digital signals, and a comparator (18) comparing incoming signals with the memory. If the signals are different to those memorized, an alarm signal (23) is set and the telephone call procedure initiated.