9 Glossary
Glossary
Active Locate
A locate where a transmitter is used to apply a signal to a buried
pipe or cable, the position of which is then located by a receiver
tuned to the same frequency.
Active Signal
A signal applied by the locator transmitter to a buried line. Typical
this is a very precise frequency.
Attenuation
The reduction of an electromagnetic signal from a pipe or cable.
Clamp (or Coupler) An accessory used to apply the transmitter signal to an insulated
line, removing the need to connect the transmitter signal directly
to a conductor or cable sheath.
Compass
Line direction indicator. (Although visually like a compass, this is
the only relation to a compass.)
Coupling
The act of signals transferring to lines to which they were not
originally applied. Coupling can be “direct” where the target line
has an electrical connection to another line, or “induced” where
the signal radiates from the target line to another line or lines.
Display
The information visually available on the dot matrix display.
Line
A generic term for any buried pipe or cable.
Null
A minimum
response to a buried line.
Passive Locate
A locate where the receiver searches for a wide range of signals
that radiate from buried pipes or cables. These signals come
from a variety of sources in the environment and couple to the
buried (& overhead) lines. Typical examples 50/60Hz and LF/
VLF radio.
Passive Signals
A wide range of signals that radiate from buried pipes or cables.
These signals come from a variety of sources in the environment
and couple to the buried (& overhead) lines. Typical examples
50/60Hz and LF/VLF radio.
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