Brain(or end station as its formally known) Bellbox
Strobe + <-------to-------> Strobe +
Strobe - <-------to-------> Strobe -
T <-------to-------> Tmp ret
A <-------to-------> Bell sw-
D (Bell +) <-------to------->...
You could try a Visonic wireless pa wrist strap, basically a watch type panic button that your mum could keep round her wrist, this will need a receiver at the end station which can be wired directly into one of the alarm zone inputs and programmed as p.a! Most security alarm suppliers will...