1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 (b) that Recommendation F.60 specifies the code expressions used for service correspondence in theinternational telex service;(c) that whilst it is desirable for the same service code expressions to be used in the radiotelex service as in theinternational
2、 telex service, because of the nature of the service the reasons for the uses of these codes may vary;(d) that agreement as to the circumstances when specific codes are used is desirable,recommends the following(1) In general for shore-to-ship calls the telex service codes specified in Recommendatio
3、n F.60 should be used.However, the telex service codes listed below should be used by the radiotelex service in the following circumstances:ABS Absent subscriber/office closed (to be used when radio contact cannot be established, i.e.radio equipment is faulty, the ship is outside the coverage area o
4、r the terminal is turned off);DER Out of order (to be used when the radio path and associated handshaking procedure is accomplished normally but the teleprinter fails to respond to the WRU signals);NC No circuits (to be used when congestion occurs in either the network or switchingequipment);NP The
5、called party is not or is no longer a subscriber (to be used when the ship numberreceived is invalid);NA Correspondence with this subscriber is not admitted (to be used if the ships number isbarred or if unauthorized group calls are attempted);OCC Subscriber engaged (to be used if the ship station i
6、s engaged)Note See also Recommendation U.61 1.(2) For ship-to-shore calls all service codes generated in the international telex service, as specified inRecommendation F.60, should be capable of being returned and presented to the calling ship subscriber.Reference1 CCITT Recommendation Detailed requirements to be met in interfacing the international telex network withmaritime satellite systems, Recommendation U.61.