IP Library › Granted Patent US 4,061,886
Granted Patent Utility
US 4,061,886 · App. 05/617,955

Dual tone multiple frequency generator

Inventors: Michael Callahan, Gordon B. Hoffman
Patented Case View Patent ↗
Granted: Dec 6, 1977 Filed: Sep 29, 1975
Inventors
Michael Callahan
Gordon B. Hoffman
Assignee (at issue)
Mostek Corporation

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Quick Facts
Patent No.
US 4,061,886
App. No.
05/617,955
Filed
1975-09-29
Granted
1977-12-06
Kind
A