IP Library › Granted Patent US 4,309,573
Granted Patent Utility
US 4,309,573 · App. 06/137,702

Loudspeaking substation circuit

Inventors: Gary Grantland, Larry A. Woodworth
Patented Case View Patent ↗
Granted: Jan 5, 1982 Filed: Apr 7, 1980
Inventors
Gary Grantland
Larry A. Woodworth
Assignee (at issue)
GTE Automatic Electric Labs Inc.

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Quick Facts
Patent No.
US 4,309,573
App. No.
06/137,702
Filed
1980-04-07
Granted
1982-01-05
Kind
A