IP Library › Granted Patent US 4,965,822
Granted Patent Utility
US 4,965,822 · App. 07/335,239

Full duplex speakerphone

Inventor: Errol R. Williams
Patented Case View Patent ↗
Granted: Oct 23, 1990 Filed: Apr 10, 1989
Inventor
Errol R. Williams
Assignee (at issue)
VideoTelecom Corp.

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Quick Facts
Patent No.
US 4,965,822
App. No.
07/335,239
Filed
1989-04-10
Granted
1990-10-23
Kind
A