IP Library › Granted Patent US 4,178,485
Granted Patent Utility
US 4,178,485 · App. 05/906,772

Transformerless telephone line circuit

Inventors: Michael C. J. Cowpland, Patrick R. Beirne
Patented Case View Patent ↗
Granted: Dec 11, 1979 Filed: May 17, 1978
Inventors
Michael C. J. Cowpland
Patrick R. Beirne
Assignee (at issue)
Mitel Corporation of Kanata

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Quick Facts
Patent No.
US 4,178,485
App. No.
05/906,772
Filed
1978-05-17
Granted
1979-12-11
Kind
A