| 摘要 |
782,085. Optical sound reproducing apparatus. TELEFUNKEN GES. Nov. 18, 1955 [Nov. 19, 1954], No. 33057/55. Class 40 (2). A signal generator adapted to transmit a combination of frequencies selected from a relatively large number of different frequencies, comprises a record carrier having a plurality of optical tracks, each corresponding to a different frequency, a plurality of photo-electric pick-up devices, one for each track, means for producing constant relative motion between record carrier and pick-up devices, and means for selectively rendering a desired combination of signal frequencies effective without switching the signal circuits. In the embodiment described, the optical tracks are carried on a disc or discs 5 rotated by a motor 3, and the individual tracks are rendered effective by closing switches 8a to 8h, inclusive, in circuit with lamps 6a to 6h, respectively, which energize a common photo-electric cell unit 7 whose output is coupled to an external circuit 10 and amplifier 11. Adjustable diaphragms in the light paths or rheostats in the lamp circuits enable amplitude adjustments to be made to individual frequencies. |
