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Detection of concealed wiring

Detection of concealed wiring

When drilling holes in walls with concealed wiring, there is a risk of drill into the wire. Find the hidden wiring in the wall using a tape recorder. To do this, connect an electrodynamic microphone to the tape recorder and turn on the instrument for recording with maximum gain. Hold the microphone along the wall. In places where the wiring is wired from the speaker, a low hum will be heard. If you move away from the wiring, the rumble will weaken. Drill safely in the place where the hum will disappear.

Source: Journal of Science and Life, No. 2, 2002 g .