1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 (b) that Recommendation F.60 specifies the operational provisions for the international telex service, and inparticular, for the composition of answer-back codes;c) that, since no single Administration is responsible for the allocation of answer-back code
2、s to ships in theway that such codes are administered in individual national telex networks, some rules further to those set down inRecommendation F.60 are desirable, for example to facilitate automatic operation in the ship-to-shore direction and tosimplify the handling of inquiries concerning call
3、s to or from ships;(d) that, to the extent possible, the alphabetic portion of maritime answer-back codes should provide a meansfor detecting possible mutilation of the numerical portion, particularly in the case of ship-to-shore calls where it may beused for charging and accounting purposes,unanimo
4、usly declaresthat, at least in cases where interconnection with the international telex network is desired, answer-back codesgenerated by teleprinters (or equivalent terminal devices) on ships shall comply with the following requirements.1 Regardless of the transmission medium used (e.g. maritime-mo
5、bile satellite, HF “direct printing”, VHF), theanswer-back code, as printed out for a distant subscriber, shall include the following three components in the orderindicated:a) the “ship stations number” of 6, 7, 8 or 9 digits (see 2 below);b) the “ships (abbreviated) name” of 4 letters (see 3 below)
6、c) the letter X, preceded by a space, as a “telex network identification code” reserved for mobile stations (seeRecommendation F.68).2 The 6, 7, 8 or 9 digits of the ship stations number are those allocated by the licensing Administration inaccordance with Recommendation F.120 but with the final 3,
7、 2 or 1 zeroes deleted for 6, 7 or 8-digit numbersrespectively.3 The letters comprising the ships (abbreviated) name 1b) above should be chosen with the guidance andunder the control of the licensing Administration with a view not only to identifying the ship (or the company, or thefleet, as is most
8、 appropriate) in a clear manner for a distant subscriber, but also to providing a means for checking theship stations number as recorded in the answer-back code. The name should not include shifts, figures or signs. Wherea ship has been allocated a 6, 7 or 8-digit number, in principle the ships (abb
9、reviated) name should not need to bechanged when the numbering plan is modified to incorporate 7, 8 or 9-digit numbers.4 The series of twenty combinations in International Telegraph Alphabet No. 2 comprising the answer-back codeshall be allocated as follows:_1)As in Recommendation F.110 and F.111, t
10、he term Maritime Mobile Service is intended to include also the Maritime Mobile-Satellite Service.2 Fascicle II.4 - Rec. F.130a) figure-shift, or (if permanently fitted) letter-shift;b) carriage-return;c) line-feed;d) the ship stations number, or (if a letter-shift is fitted in the first position) f
11、igure-shift followed by the shipstations number;e) letter-shift;f) space, which should however be omitted if both the ship stations number consists of 8 digits and a letter-shift is fitted in the first position;g) the ships (abbreviated) name;h) space;i) if necessary, a letter-shift or letter-shifts
12、 to bring the total number of combinations in the answer-back codeup to twenty;j) the letter X;k) letter-shift (it- permanently fitted).5 The technical requirements for answer-back generators are laid down in Recommendation S.6.6 In accordance with Recommendation S.6, it is preferred that teleprinte
13、rs having all 20 positions in the answer-back which are freely assignable should be used in the future, i.e. where the first position is a figure-shift and the lastthe letter X. In the meantime, teleprinters that have a letter-shift permanently fitted in the first and last positions of theanswer-back code may be used where the ship stations number does not exceed 8 digits.
