Telephone equipment with multiple function

  • US 4,903,289 A
  • Filed: 03/24/1988
  • Issued: 02/20/1990
  • Est. Priority Date: 03/24/1987
  • Status: Expired due to Term
First Claim
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1. Telephone equipment with multiple functions capable of operating off-hook dialing following picking up of a handset of a phone and on-hook dialing by turning on a special off-hook switch of the phone, using a DTMF (dual-tone multifrequency) tone, and incorporating an additional device that can be controlled (1) by remote control by signals from an external source over an outside telephone line by pushing DTMF tone buttons of the external source, and (2) manually and independently of the outside telephone line by pushing DTMF tone buttons of said equipment of the same numeral or sign as those for remote control operation of the additional device over the outside telephone line, said equipment including circuitry for automatically making the additional device independent of the outside telephone line during an off-hook dialing operation of said telephone equipment for placing an outgoing call, and thereafter during the time a talking circuit on the telephone line is established by the outgoing call, enabling said additional device to be controlled either by a calling party by a remote control operation or by a called party.

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