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1975-09-17 |
Gen Electric Co Ltd |
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1973-03-23 |
1975-01-14 |
Nitsuko Ltd |
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1973-03-26 |
1975-06-10 |
Northern Electric Co |
Loudspeaking communication terminal apparatus and method of operation
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1973-03-30 |
1974-11-27 |
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1973-12-07 |
1975-09-30 |
Jacobson Sava |
Speaker telephone
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1973-12-12 |
1977-06-07 |
Nippon Electric Company, Ltd. |
Maximum value tracing circuit for digitized voice signals
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1974-05-02 |
1979-05-12 |
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1974-06-27 |
1976-06-15 |
Stromberg-Carlson Corporation |
Loudspeaking telephone hysteresis and ambient noise control
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1974-06-27 |
1976-07-20 |
Stromberg-Carlson Corporation |
Loudspeaking telephone with improved receive sensitivity
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1974-09-27 |
1976-08-25 |
Gen Electric |
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1974-10-29 |
1976-10-13 |
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1974-12-12 |
1976-04-27 |
Northern Electric Company, Limited |
Digital control of a loudspeaking telephone system
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1975-06-30 |
1979-07-10 |
International Standard Electric Corporation |
Two-way loudspeaking device for telephone stations
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1977-04-11 |
1978-09-19 |
Williams Richard W |
Two way telephone amplifier
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1977-06-16 |
1978-09-19 |
Abram N. Spanel |
Electroacoustical telephone adapter
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1978-09-28 |
1980-04-10 |
Siemens Ag |
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1980-08-29 |
1984-05-31 |
Western Electric Co |
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1980-12-23 |
1983-03-29 |
Motorola, Inc. |
Radiotelephone with hands-free operation
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1981-08-21 |
1985-08-20 |
Plantronics, Inc. |
Voice communication instrument system with line-powered receiver conditioning circuit
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1981-12-31 |
1988-08-09 |
Howard Siegel |
Monitoring apparatus using telephone link
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1982-04-05 |
1983-08-23 |
Motorola, Inc. |
Speakerphone for radio and, landline telephones
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1983-02-18 |
1984-12-25 |
At&T Information Systems Inc. |
Speakerphone control circuit
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1987-07-06 |
1989-01-17 |
Nec Corp |
Variable gain circuit for loudspeaker telephone set
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1987-09-09 |
1988-11-22 |
The Dow Chemical Company |
Asphalt compositions containing anti-stripping additives prepared from amines or polyamines and phosphonates
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1987-12-30 |
1989-11-07 |
Plantronics, Inc. |
Voice communication link interface apparatus
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1988-12-28 |
1990-09-25 |
At&T Bell Laboratories |
Acoustic calibration arrangement for a voice switched speakerphone
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At&T Bell Laboratories |
Enhanced acoustic calibration procedure for a voice switched speakerphone
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Southwestern Bell Technology Resources, Inc. |
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1993-05-25 |
1994-12-06 |
Exar Corp |
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Motorola, Inc. |
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1997-11-25 |
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1998-09-02 |
Casio Phonemate Inc |
Speakerphone, speakerphone system and method of operating a speakerphone
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