On 2/27/2013 12:13 AM, StephenB wrote:

How about hooking up a compressor and listen for the air escaping the
other end?

Oh ... I like that! Good thinking-outside-the-box.

Going with that idea and if you are positively, absolutely,
unequivocally certain that there is no power anywhe use water (stick
a hose in the conduit).

Bob