Why should you never place the transmitter directly on a metal pipe or valve box?

• A. It will drain the transmitter battery.
• B. It will cause distortion.
• C. It will produce an inaccurate reading.
• D. It will void the warranty.

Answer: (B)

Placing the transmitter on metal creates a direct, low-impedance path to ground and can act as a shield. The transmitter is meant to couple energy into the pipe itself, but when it sits on a metal surface, part of that energy is diverted into the metal or ground rather than along the pipe. This changes the way the signal propagates and distorts the electromagnetic field, making the readings from the receiver unreliable. To get a clean, accurate signal, the transmitter should be coupled directly to the pipe (or placed on a non-conductive surface) so the energy stays focused along the line rather than being distorted by nearby metal.