Speaker phones
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United States of America Patent
Stats
-
Aug 24, 1982
Grant Date -
N/A
app pub date -
Mar 17, 1980
filing date -
Mar 17, 1980
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A speaker telephone system having hands-free telephone sets with microphones and loud-speakers and including circuitry for preventing feedback between the loud-speakers and the microphones in both the transmitting and receiving modes by automatically controlling the amplification of the signals coming from the microphones and going to the loud-speakers, as a function of the signal direction, while still maintaining the microphones and loud-speakers electrically coupled to the telephone lines.
First Claim
Family
International Classification(s)
Cited Art Landscape
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