| 摘要 |
1349484 Line transmission systems SOC D'ETUDES TECHNIQUES ET D'ENTREPRISES GENERALES 16 June 1971 [19 June 1970] 28328/71 Heading H4R In a system for selectively distributing information from a central station to subscribers, all information is fed to each subscriber station and applied to a recorder thereat and before each information block is transmitted a classification code is entered into the system via a keyboard or other manual input and means at the central station responds to the code and enables the recorders at those subscriber stations associated with the code. In one embodiment as shown an operator reads into a microphone 9 from documents. Before reading each document a classification code is entered at a keyboard 1 and is automatically compared at 3, 30 0 to 30 n with codes in memories 2, 20 0 to 20 n each associated with a subscriber and storing the classification codes of matter that particular subscriber is interested in. Those comparators which detect a match set corresponding flipflops 5, 15 0 to 15 n , the set ones of which supply a recorder enabling potential to the subscriber station via a line such as 6. The enabled tape recorders record the spoken information received via their line and D.C. isolating capacitors such as 11 and 12. In other embodiment not shown enabled key combinations set flipflops (either simultaneously or successively in which case the flip-flops are in successive stages of a stepping register) or in accordance with the classification code on the document and arrays of AND and OR logic wired in accordance with the particular codes of interest to individual subscribers provide the recorder enabling signals. The use of a programmed computer to supply the gating signals is also suggested. |
