DK32005C
(en )
1923-07-23
Apparatus for reproducing or recording sound.
DK34877C
(en )
1925-08-17
Device for recording and reproducing sound.
AT112399B
(en )
1929-02-25
Sound recording and reproducing apparatus.
DK42626C
(en )
1930-07-21
Apparatus for recording and reproducing sound.
DK25063C
(en )
1919-09-22
Procedure for Writing Down and Reproducing Sound.
DK30765C
(en )
1922-11-20
Device for recording and reproducing sound.
DK33891C
(en )
1924-11-17
Cinematographic Apparatus for Recording and Playback.
DK32963C
(en )
1924-03-17
Device for recording sound in connection with cinematographic recordings.
AT110999B
(en )
1928-10-25
Turntable drive for sound recording and reproducing apparatus.
DK32388C
(en )
1923-10-15
Device for photographic recording of sounds.
DK32687C
(en )
1923-12-31
Apparatus for recording and reproducing sounds and vivid images.
ES76347A1
(en )
1921-02-16
Apparatus for dictating phonograph.
DK36883C
(en )
1926-12-06
Sound reproducing apparatus.
DK51820C
(en )
1936-06-29
Apparatus for reproducing sound.
DK38510C
(en )
1928-03-05
Sound reproducing apparatus.
DK37820C
(en )
1927-08-15
Sound reproducing apparatus.
DK32596C
(en )
1923-12-10
Device for sound reproducing apparatus.
DK33968C
(en )
1924-12-22
Apparatus for apparatus for recording and reproducing phonographic sound waves.
DK39794C
(en )
1929-02-11
Sound reproducing apparatus.
AT96099B
(en )
1924-02-25
Cinematographic recording apparatus.
DK32869C
(en )
1924-02-18
Photographic Sound Recording.
DK32243C
(en )
1923-09-10
Apparatus for photographic recording of sound waves on a recording tape.
AT98602B
(en )
1924-11-25
Apparatus for photographic sound recording.
DK24055C
(en )
1919-02-10
Procedure for Refreshing Gramophone Records.
DK39198C
(en )
1928-09-03
Sound reproduction apparatus.