headphones. Then move the ferrite antenna on both sides. Part of the magnetic field
lines will be passing through the coil on both sides, which will generate induced
electromotive force, so that you can hear the audio sound the headphones. With the
slow movement of magnetic antenna, the sound gradually becomes larger. When
moving to a certain distance, the sound will be the maximum. Move a further distance,
and the sound will gradually become weakened. In the vicinity of the cable, the sound
and its position relationship forms a saddle-shaped curve with trough corresponding
to the test position, which is the specific location of buried cables. Connecting all of
the troughs(lightest point) will be the laid path of the cable.
From top to bottom:
接收到的磁场强度曲线：
Received magnetic field strength
curve
