Hahnemann 1928
Walter Hahnemann, Kitzberg, Germany, assigned rights to Lorenz Aktiengesellschaft. "Arrangement for Uniform Electrical Sound Transmission". Filed: 1926 U.S. Patent 1,674,683 Granted: June 26, 1928

Hahnemann 1928

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Filed: March 24, 1926
U.S. Patent 1,674,683
Granted: June 26, 1928

Walter Hahnemann, Kitzberg, Germany, assigned rights to Lorenz Aktiengesellschaft.
"Arrangement for Uniform Electrical Sound Transmission".

Referenced by Walker and Williamson in U.S. Pat. 3,008,013