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United States Patent | 4,560,837 |
Carson , et al. | December 24, 1985 |
In the disclosed call transfer method and circuitry, audibly distinguishable ringing signals at a station set enable an answering party to determine whether a received call is either the original call or a previously answered call. Line status LEDs at each station set give specific visual indications to trace the progress of a call transfer.
Inventors: | Carson; Robert A. (Indianapolis, IN), Fenton; Francis M. (Middletown, NJ), Jones; David F. (Middletown, NJ) |
Assignee: |
AT&T Information Systems Inc.
(Holmdel,
NJ)
|
Appl. No.: | 06/523,092 |
Filed: | August 15, 1983 |
Current U.S. Class: | 379/212.01 ; 379/373.02; 379/911; 379/914 |
Current International Class: | H04Q 3/62 (20060101); H04M 3/54 (20060101); H04M 9/00 (20060101); H04M 003/58 (); H04Q 001/30 () |
Field of Search: | 179/18BD,99P,99M,99R,99LS |
3665112 | May 1972 | Blake et al. |
3800098 | March 1974 | Evans et al. |
4338495 | July 1982 | Bloch et al. |
60153 | May., 1981 | JP | |||
65953 | Apr., 1982 | JP | |||
"Horizon.RTM. Communication System: Custom Service for Small Businesses", Bell Laboratories Record, vol. 55, No. 10, Nov. 1977, pp. 271-275.. |