Before revision: De Forest's initial Audions did not have a high vacuum and developed a blue glow at modest plate voltages; De Forest improved the vacuum for Federal Telegraph.DeForest Radio Co. v. General Electric Co., 283 U.S. 664 (May 25th , 1931).
After revision: De Forest's initial Audions did not have a high vacuum and developed a blue glow at modest plate voltages; De Forest improved the vacuum for Federal Telegraph.DeForest Radio Co. v. General Electric Co., 283 U.S. 664 (May 25 , 1931).