Pig Trackers and Pingers Pig Trackers mainly differ from detectors in that the pig is usually equipped with a transmitter that emits a signal that can be tracked by operators. Normally,
this is used when pigs become lost or stuck in the pipeline. Units can be sold or rented. Operators are able to physically walk the line and pick-up the
signal emitted by the transmitter. The difference between Trackers and Pingers is that transmitters are equipped with an on/off switch and pingers are activated once they come in contact with a liquid.
Pingers are known for their use in the "black box" on airplanes.
