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US2810020A
|
Magnetic head for sound-recording apparatus and the like |
Expired / Lapsed
|
1951-06-19 |
1957-10-15 |
0 |
Details
|
|
FR893135A
|
Device keeping the current supplied by an amplifier lamp co… |
Expired / Lapsed
|
1943-04-06 |
1944-05-31 |
0 |
Details
|
|
US2223033A
|
Strip feeding for sound and sound picture systems |
Expired / Lapsed
|
1937-04-09 |
1940-11-26 |
0 |
Details
|
|
US2085205A
|
Method and means to scan sound films with a plurality of sc… |
Expired / Lapsed
|
1935-03-26 |
1937-06-29 |
0 |
Details
|