The series of groups listed in this Annex range from QOA to QUZ. The QOA to QQZ series are reserved for the maritime mobile service. Certain Q code abbreviations may be given an affirmative or negative sense by sending, immediately following the abbreviation, the letter C or the letters NO (in radiotelephony spoken as: CHARLIE or NO).
ITU-R M.1172 FRENCH-1995 history
1995ITU-R M.1172 FRENCH-1995 MISCELLANEOUS ABBREVIATIONS AND SIGNALS TO BE USED FOR RADIOCOMMUNICATIONS IN THE MARITIME MOBILE SERVICE