Janszen 1949
Arthur A. Janszen, Cambridge, Mass. "Electrostatic Loud-Speaker" Filed: October 5, 1949 U.S. Patent 2,631,196

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Filed: October 5, 1949
U.S. Patent 2,631,196
Granted: October 5, 1953

Arthur A. Janszen, Cambridge, Mass.
"Electrostatic Loud-Speaker"

Referenced by Walker and Williamson in U.S. Pats. 3,008,013 & 3,008,014.