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Transmitter for emitting reference signal to distinguish false signals in cable locating

  • US 9,804,287 B2
  • Filed: 04/15/2016
  • Issued: 10/31/2017
  • Est. Priority Date: 04/13/2005
  • Status: Active Grant
First Claim
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1. A transmitter as part of a cable locating system for use in a region which contains at least first and second in-ground cables, each of which cables includes an electrically conductive component such that, when the first cable is driven at a locating signal frequency to emit a locating signal in an electromagnetic form, the locating signal is coupled to the second cable in a way which causes the second cable to generate a false locating signal in electromagnetic form, said transmitter comprising:

  • an apparatus for generating said locating signal frequency for coupling onto the first cable and for transmitting a reference signal, which includes said locating signal frequency modulated thereon such that the reference signal includes a modulation envelope for comparison of the modulation envelope to the locating signal and to the false locating signal at a receiving location to distinguish the locating signal from the false locating signal.

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