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Telephone tactile alert system

  • US 4,421,953 A
  • Filed: 12/07/1981
  • Issued: 12/20/1983
  • Est. Priority Date: 12/07/1981
  • Status: Expired due to Term
First Claim
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1. A system for non-audibly alerting a telephone user when the telephone is being energized by ringing volage, the system comprising (i) a telephone unit for coupling to the telephone line, the telephone unit including a sensing means for sensing successive ringing voltage bursts and a transmitter adapted to emit a signal burst in response to each successive ringing voltage burst, and (ii) a user unit including a receiver for receiving the signal bursts from the transmitter and a transducer under the control of the receiver for converting the received signal into a non-audibly sensible signal.

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