"Brian" wrote in message
...
...
To my surprise, the continuity tester "chirped" - beeped briefly - and its
LED flashed briefly, before remaining silent. Continuity is normally
indicated by a steady beep and a lit LED.

Now I presume that this is normal - some kind of side effect of the RCD,
or
something like that? Has anybody else used one of these devices and had a
similar result?

Sounds like there is a capacitor in the circuit. That would conduct briefly,
until it was charged up. If you swap the leads over and test the continuity,
it is likely to chirp again, and again when you swap them back over.
Capacitors are used, amoung other places, across switches to suppress RFI.

-- Jason