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Thomas Edison made these notes on March 30, 1911 for his patent attorneys, who were preparing an application for an improved disc phonograph sound box. Many of Edison's patents covered design changes for existing inventions or improved manufacturing methods. This new sound box was part of Edison's ongoing efforts to improve the quality of his disc phonograph in 1911. Edison signed the application on April 3, 1911 and received patent #1,078,266 in November 1913. |
Last updated: February 26, 2015