I need to "find" an old recessed wall socket (incoming telephone jack in concrete wall) that has been covered with spackle when the wall was fully spackled. Is there any instrument that can locate the cavity (like an inverted stud finder or similar)? Or is the only option to start chipping away the plaster until I find it?
There is equipment that emits a signal on the wires, and then you go with a detector that locates where the wires are. You will probably also find the box in that case. Do not know if it's available for rent. I would think that many electrical companies have the equipment.
