[Shop-talk] finding buried gate wiring

[Eric Murray]

I have an electric gate on my driveway about 700' from the house, 
installed before I bought the house.  There is a set of twisted pair 
wiring from the phone box to the gate to remotely operate it. along with 
120v power and a couple signal wires.  I need to locate all the junction 
boxes along the path, and I can't find one. Or rather the contractor who 
is going to replace the wiring can't find it.

The wires are in plastic conduit buried about 1' down.  The junction 
boxes are "Christy" concrete boxes.

I have a cheap metal detector.  Would it be able to pick up the wiring?  
Any other ideas for finding the missing box?  Divining rods?

I have not tried yet because I just thought about using the detector 
last night and I injured my leg last week and don't want to walk more 
than I have to.

Eric