On 18/10/2016 17:07, F wrote:
Probably a daft question, but I wanted to check...

I noticed earlier today that the top of the alarm bell box is missing!
Old and brittle plastic?

A search on Ebay comes up with what seems to be a choice of bell boxes
with sirens and LEDs inside, and 'dummy' bell boxes.

I don't need the innards so, will a dummy do the job? Is the 'dummy'
just the fully featured box minus the features?

A further thought... am I correct in suspecting that the dummy boxes are
minus tamper switches?

--
F