On 23/05/2016 16:25, Bill wrote:
In message , Andy Burns
writes
GB wrote:

Would one of those cheapo combined stud/cable finders work?

When set to detect live cables, my Bosch GMS120 will detect a piece of
plasterboard that's in contact with a mains cable at about 18" (i.e.
useless false negative) but it won't detect SWA even when touching it.
In metalwork mode it detects the SWA, but not at any useful distance.


We did try his stud finder, but nothing.

He also has a warbly-tone cable tracer, but it appeared to have lost all
its gain at one end or the other. It said 120dB output in the
instructions, but we had to hold it about 6 inches away to hear it at all.

Stick 240V on the armour. Make sure the other end is genuinely isolated.

Then try the cable finder. Of course it is possible that all the earth
above will shield the cable.