43
4. With the Locator turned on, walk from the pipe access
point in the direction that the Sonde was pushed. A strong
peak signal directly over the Sonde should be detected with
two lesser ‘ghost’ signals found, one in front of and one
behind the Sonde’s true position. These ghost signals
are always weaker than the main signal and should
not be mistaken for the true Sonde signal.
5. Pinpoint the Sonde’s exact position by moving the Locator
first backwards and forwards and then from side to side
to get the peak response on both occasions.
6. Push the Sonde further up the pipe and repeat
the pinpointing process.
See page 48 for depth measurement using a Sonde.
Non-Metallic Pipe Tracing using a Sonde:
Tracing a Sonde
ghost
signal
ghost
signal
true
signal