Conference telephone system and method

Telephonic communications – Substation or terminal circuitry – For loudspeaking terminal

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Details

379394, 379391, 379 6, 379400, H04M 100

Patent

active

051724103

ABSTRACT:
A speaker telephone comprising a microphone outputting an electrical signal, and a loudspeaker is disclosed. An amplifier has its output coupled to the loudspeaker. This amplifier has non-inverting and inverting inputs. A switch having two positions couples the microphone to the amplifier or couples the tuning signal source to one of the inputs of the amplifier. A tuning signal source and control circuit output a tuning signal. Initiation means initiates a tuning sequence by causing the switch to be in the second position and causing the tuning signal source and control circuit to generate tuning signals. A coupling device is connected to one of the inputs of the amplifier and adopted to be connected to a telephone circuit. A hybrid voltage generator circuit is responsive to the output of the microphone when the switch couples the microphone to the amplifier to generate at its output a cancellation signal which prevents transmitted voice signals from appearing at the loudspeaker.

REFERENCES:
patent: 3177295 (1965-04-01), Lane et al.
patent: 3582563 (1971-06-01), Cragg
patent: 3708630 (1973-01-01), Matsuda et al.
patent: 3810247 (1974-05-01), Ono
patent: 3982078 (1976-09-01), Janssen et al.
patent: 3982080 (1976-09-01), Ukeiley
patent: 4394542 (1983-07-01), Hara et al.
patent: 4602338 (1986-07-01), Cook
patent: 4634964 (1987-01-01), Chattler
patent: 4887288 (1989-12-01), Erving
patent: 4910768 (1990-03-01), Sues et al.

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