|
US1946404A
|
|
Reproduction of sound from sound film records
|
|
GB384417A
|
|
Improvements in or relating to the reproduction of sound from sound film records
|
|
US1939355A
|
|
Process and apparatus for the production of sounds of any desired tone color
|
|
US1930362A
|
|
Talking film
|
|
GB360940A
|
|
Improvements in or relating to talking films
|
|
US1951939A
|
|
Light source
|
|
GB350280A
|
|
Improvements in or relating to apparatus for recording sound waves on a photo-sensitive support
|
|
GB349019A
|
|
Improvements in or relating to electrical sound reproducing apparatus
|
|
GB316623A
|
|
Improved method of and apparatus for copying talking films
|
|
US1863560A
|
|
Apparatus for recording electric alternating currents by means of a voltaic arc
|
|
GB226525A
|
|
An improved alternating current relay
|
