Signalman 1 & C - Historic Naval Ships Association

serious confusion at sea. Sound signaling in fogshould, therefore, be reduced to a minimum. Signalsother than the single-letter signals should be used onlyin extreme emergency and never in frequentednavigational waters.The signals should be made slowly and clearly.They may be repeated, if necessary, but at sufficientlylong intervals to ensure that no confusion can arise andthat one-letter signals cannot be mistaken fortwo-letter groups.Under international procedures, a transmittingship calls in the same manner as by flashing light;the receiving ship replies with the answering sign.(No call or answer is sent, however, when transmittingsingle-letter signals.) The transmitting shipthen sends the entire message. Unless the receivingship misses a word or group, it does not answer untilthe ending AR is made; it then indicates receipt bysending R.If the receiving ship misses a word or groupduring the transmission, it immediately signals RPTto indicate the omission; the transmitting ship goesback a few words or groups, then continues themessage. Ships do not exchange identities in thisform of communication despite use of the generalcall AA.RADIOTELEPHONEWhen using the International Code of Signalsin cases of language difficulties, the principles of theRadio Regulations of the International TelecommunicationsUnion then in force have to beobserved. Letters and figures are spelled outaccording to phonetic spelling tables. When coastand ship stations are called, the identity signals ornames shall be used.CallingThe call consists of the call sign or name of thestation called, the group DE, and the call sign or nameof the calling station.Difficult names of stations should be spelled.After contact has been established, the call sign orname need not be sent again.AnsweringThe reply to a call consists of the call sign of thecalling station, the group DE, and the call sign or nameof the station called.General InformationWhen calling all stations in the vicinity, the groupCQ is used.To indicate that groups are from the InternationalCode of Signals, the word INTERCO is inserted. Thegroup YZ will be used when plain language is used inthe text.The signal AS is used when the station called isunable to receive traffic immediately.To receipt for a transmission, the signal R is used.Repetitions are obtained by RPT followed byprowords if needed.To end a transmission, the signal AR is used.MORSE SIGNALING BY HANDFLAGS OR ARMSA station that desires to communicate withanother station by Morse signaling using hand flags orarms may indicate the requirement by transmitting tothat station the signal K1 by any method. The callsignal AA may be made instead.On receipt of the call, the station addressed shouldmake the answering signal or, if unable tocommunicate by this means, should reply with thesignal YS1 by any available method.The call signal AA AA AA and the signal T shouldbe used, respectively, by the transmitting station andthe addressed station.Normally both arms should be used for thismethod of transmission, but in cases where this isdifficult or impossible, one arm can be used.All signals will end with the ending signal AR.Figure 6-1 shows positions for Morse signaling byhand flags or arms.SINGLE-LETTER SIGNALSInternational single-letter signals, which may bemade by any method of signaling, have specificmeanings that in most cases do not parallel the same6-8