United States Patent 1690279
Publication Date:
11/06/1928
Export Citation:
Primary Class:
Other Classes:
236/69, 246/169S, 315/76, 315/156, 315/201, 315/208, 315/250, 324/128, 324/133, 340/4.4, 340/332, 362/276, 362/811, 369/70, 369/175
International Classes:
G10L21/06
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