IP Library Granted Patent US 4,956,862
Granted Patent Utility
US 4,956,862 · App. 07/305,785

Method of providing sound privacy system compatible with mono and btsc stereo audio

Inventors: Clyde Robbins, John Schilling
Patented Case View Patent ↗
Granted: Sep 11, 1990 Filed: Feb 2, 1989
Inventors
Clyde Robbins
John Schilling
Assignee (at issue)
General Instrument Corporation

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.

Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 4,956,862
App. No.
07/305,785
Filed
1989-02-02
Granted
1990-09-11
Kind
A