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Telephone technician's terminals with auto-selection of dial pulse on DTMF signalling

  • US 4,922,516 A
  • Filed: 06/02/1989
  • Issued: 05/01/1990
  • Est. Priority Date: 01/25/1988
  • Status: Expired due to Fees
First Claim
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1. Apparatus for determining the type of customer signalling, whether dial pulse or dual tone nulti-frequency, when randomly connecting into a subscriber line of a telephone system, comprising:

  • means for seizing a selected telephone subscriber line and receiving dial tone;

    means for outpulsing the first digit of a selected telephone number in dual tone multi-frequency signal;

    means for selectively sensing absence and presence of said dial tone;

    means responsive to absence of dial tone for outpulsing all remaining digits of the selected telephone number in dual tone multi-frequency signals to complete the call; and

    means responsive to presence of dial tone for outpulsing the first and all remaining digits of the selected telephone number in dial pulse signals to complete the call.

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