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US2621260A
|
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Electrical sound recording, reproducing, and like apparatus
|
|
US2113907A
|
|
Electric pick-up
|
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US2038687A
|
|
Acoustic translating device
|
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US1933457A
|
|
Sound-recording machine
|
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US1621180A
|
|
Electromagnetic apparatus for recording sound
|
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US1637397A
|
|
Telephone transmitter and receiver
|
|
US1743251A
|
|
Means for recording sound
|
|
US1594802A
|
|
Telephone transmitter and receiver
|
|
US1639713A
|
|
Reproduction of sound
|
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US1428819A
|
|
Manufacture of sound records
|
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US1428818A
|
|
Production of sound records
|
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US1711551A
|
|
Reproducing and recording of sound
|
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US1360330A
|
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Means for detecting and locating subaqueous sounds
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