1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 3 TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU4%,%2!0(9!,0(!“%4)#!,G0G04%,%2!0(G0G04%2-).!,%15)0-%.435002%33)/.G0G0/amended at New Delhi, 1960)The CCITT,considering(a) that in a radiotelegraph system in which a radio teleprinter transmitter broadcasts me
2、ssages simultaneouslyto a number of receiving stations, this broadcast is sometimes required only by a restricted number of these stations;(b) that it is desirable in such cases to prevent the reception of the message at the other offices to avoidwastage of paper;(c) that such wastage can be avoided
3、 by the use of selective calling systems whereby only those stationsrequired to receive the transmission are connected whilst it is in progress;(d) that various technical methods are available for achieving this, using either pulse signalling (e.g. by dial),or signalling with 5-unit signals;(e) that
4、 a wide variety of systems may be devised based upon the methods in (d) above;(f) that such systems are normally used only for special services in which agreement can be reached on theparticular type of system to be adopted;unanimously declares the view(1) that, when it is desired to avoid wastage of paper at receiving stations in radiotelegraph multi-destinationteleprinter systems, a selective calling system should be used;(2) that it is neither necessary nor desirable to recommend the use of any particular type of system forinternational use.
