| 摘要 |
<p>1,194,062. Receiver channel selectors. COMPAGNIE FRANCAISE THOMSON HOUSTON-HOTCHKISS BRANDT. 29 Jan., 1968 [3 Feb., 1967], No. 4555/68. Addition to 1,193,783. Heading H3Q. In a radio frequency channel selector, for receiving apparatus such as television, a hollow rotary drum 12 supports a series of cards 19 and photo-sensitive elements 21 are mounted in a block of moulded material, such as plastics, which is fixed to a frame 5, 16 by a support-plate 22 disposed inside the drum, the arrangement is such that any one of the cards can be positioned so that the photo-sensitive elements located opposite perforations or transparent portions of the card are illuminated by one or more fixed electric lamps 24 located externally of the drum to provide a control voltage modifying the capacity of variable capacitance elements to tune the associated stages of the receiver. As shown, the photo-diodes are connected by a printed plate 22 to electronic circuits of the television receiver so as to effect selection of the channel corresponding to the punched card selected. The drum 12 is biased in a certain position by a spring 13. When the key TD (Fig. 4) is pressed, rod D moves the end g of a member 31 against a lever 6 which is driven anti-clockwise. A braid 9 attached to a shaft 10 on the lever 6 is pulled against the action of spring 13 and rotates the drum 90 degrees. Similarly by pressing the keys TE and TF, members 33 and 29 engage and move the lever 6 at h and j to move the drum to the 180 and 270 degree positions, respectively. When a key is pressed it releases any previously depressed key and its associated rod is locked by a device 4. Key TC merely acts to release any of the other keys and allows the spring 13 to return the drum 12 to the 0 degrees position, also key TC may operate the mains circuit-breaker A of the receiver. The lamps 24 and channel cards which are inserted in grooves 19 in the drum may be replaced through a removable part 35 of the casing of the receiver. The lamps have a reflector 18 which has a mirror (26, Fig. 3a, not shown), at the front so that the channel number (28, Fig. 3e, not shown), which is marked on each punched card, can be seen through a lens 27 in the casing of the receiver.</p> |
