IP Library Granted Patent US 4,427,847
Granted Patent Utility
US 4,427,847 · App. 06/291,655

Television/telephone system with annunciator and intercom feature

Inventors: Judson A. Hofmann, Paul A. Snopko
Patented Case View Patent ↗
Granted: Jan 24, 1984 Filed: Aug 10, 1981
Inventors
Judson A. Hofmann
Paul A. Snopko
Assignee (at issue)
Zenith Radio Corporation

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Quick Facts
Patent No.
US 4,427,847
App. No.
06/291,655
Filed
1981-08-10
Granted
1984-01-24
Kind
A