71573880
Feb 15, 1949
Oct 2, 1951
ELECTRICAL INSTRUMENT EQUIPPED WITH AN OPTICAL SYSTEM FOR VISIBLY RECORDING VARIATIONS OF ELECTRIC CURRENT WHEREIN THE VARIATIONS IN THE CURRENT CAUSE INVISIBLE RADIATIONS TO IMPINGE UPON A MOVING SENSITIZED SHEET AND PRODUCE A VISIBLE TRACE ILLUSTRATING THE OSCILLATIONS OR VARIATIONS IN THE ELECTRIC CURRENT AS THEY OCCUR
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