Operating signals, also called Q and Z codes, are used throughout the world. They are used by both civil and military organizations. The most complete list of both Q and Z signals is found in ACP 131(F). This is the standard guide for use by the NATO military forces.
Q signals are normally used in Morse code transmissions. Z signals are generally used only in military digital transmissions. We will ignore the Z signals and concentrate on the Q signals.
Q signals are three letter codes that begin with the letter ‘Q’. They range from QAA to QZZ. The Q signals are divided up into several different sections and allocated to particular uses. The series QAA through QNZ are defined by the International Civil Aviation Organization for aeronautical use. QOA through QQZ are reserved for maritime use. The series QRA through QUZ are defined by the International Telecommunications Union (ITU) and are in use at virtually every civil station throughout the world.
Amateur radio has adapted some of these Q codes for use in amateur communications. These Q codes come from the ITU civil series QRA through QUZ. Most of the meanings are identical to the ITU definitions, however, they must be looked at in the context of amateur communications. For example, QSJ? asks what the charges are for sending the telegraph. Since amateur communications are without charge, this Q code would not make sense.
Q codes are either sent with or without a question mark (CW: di-di-dah-dah-di-dit). A Q code with a question mark is to be understood as asking a question. A Q code without a question mark is to be understood as an affirmative answer to a question asked or as a direct statement. For example, if you say QRA?, you are asking the question: “what is the name of your station”. If you are asked this question, you could answer: “the name of my station is WB8AAA”. In a maritime service, you might have answered QRA Newport, meaning that the name of your station is Newport. In the context of an amateur radio conversation, the name of your station is commonly understood to be your station callsign. Always keep in mind that radio amateurs are communicating in an amateur radio context and that Q codes should be interpreted in that context.
Amateur radio actually has adapted two different sets of Q codes. The one in most common use is the Q codes From QRA through QUZ. The second set is the set of Q codes, used only in ARRL NTS nets, that begin with QN. These Q codes generally have no equivalent in the ACP 131 publication and are specifically defined only for use in NTS nets. They are not used in casual amateur radio communications.
INTERNATIONAL Q SIGNALS QRA What is the name of The name of my station your station? is _____ QRG What is my exact Your exact frequency frequency? is ____ (KHz or MHz) QRH Does my frequency vary? Your frequency varies. QRI How is my tone? Your tone is _____ 1 Good 2 Variable 3 Bad QRK What is my signal Your signal intelligibility intelligibility? (or that of ___) is ____. 1 Bad 2 Poor 3 Fair 4 Good 5 Excellent QRL Are you busy? I am busy. QRM Are you being I am being interfered interfered with? with ____. 1 nil 2 slightly 3 moderately 4 severely 5 extremely QRN Are you troubled by I am troubled by static ___. static? 1 nil 2 slightly 3 moderately 4 severely 5 extremely QRO Shall I increase Increase tranmitter power. transmitter power? QRP Shall I decrease Decrease transmitter power. transmitter power? QRQ Shall I send faster? Send faster. QRS Shall I send slower? Send slower. QRT Shall I stop sending? Stop sending. QRU Have you anything I have nothing for you. for me? QRV Are you ready? I am ready. QRW Shall I tell _____ you Tell ____ I am calling him. are calling him? QRX When will you call I will call again at _____. again? QRZ Who is calling me? You are being called by ____. QSA What is my signal Your signal strength is ____. strength? 1 scarcely perceptible 2 weak 3 fairly good 4 good 5 very good QSB Are my signals fading? Your signals are fading. QSD Is my keying defective? Your keying is defective. QSG Shall I send _____ Send ____ messages at a time. messages at a time? QSK Can you work breakin? I can work breakin. QSL Can you acknowledge I can acknowledge receipt. receipt? QSM Shall I repeat the last Repeat the last message sent. message sent? QSO Can you communicate I can communicate with with _____ direct? _____ direct. QSP Will you relay I will relay to _____. to _____? QSV Shall I send a series Send a series of V's. of V's? QSW Will you transmit on __? Transmit on _____. QSX Will you listen to I am listening to ______ ______ on ____? on ________. QSY Shall I change Change frequency to _____. frequency? QSZ Shall I send each Send each word/group twice. word/group more (or _____ times) than once? QTA Shall I cancel Cancel number _______. number _____? QTB Do you agree with my I do not agree with your word word count? count. I will repeat the first letter or digit of each word or group. QTC How many messages do I have ____ messages to send. you have to send? QTH What is your location? My location is _______. QTR What is your time? My time is ______. QTV Shall I stand guard Stand guard for me on _____. for you on ______? QTX Will you keep your I will keep my station open station open for furthur for further communication communications with me? with you. QUA Have you news of _____? Here is news of ______. Several of the above Q codes can have various other items of information added to them depending on the context. Such information might include times, dates, names, or frequencies. Some of the above Q codes are commonly used in ways that are slightly different than the above formal definitions. For example, QRL? is commonly used to mean: "Is this frequency in use?". Remember, context matters, common usage can vary, and amateur radio is a hobby. ARRL QN Signals For CW Net Use The following ARRL-defined QN signals are only for use on NTS CW nets. They are not for use on phone nets. Say it with words on phone nets. Q signals followed by an '*' are for use only by the net control station. QNA* Answer in prearranged order. QNB* Act as a relay between _____ and _____. QNC All net stations copy. I have a message for all net stations QND* This net is directed (controlled by a net control stn). QNE* Entire net stand by. QNF Net is free (not controlled). QNG Take over as net control. QNH Your net frequency is high. QNI Net stations report in (by net control) or I am reporting into the net (by net stations). QNJ Can you copy me? ( or can you copy _____?) QNK* Transmit message for _____ to ______. QNL Your net frequency is too low. QNM* You are QRMing the net. Stand by. QNN Net control station is ______. or What station is NCS? QNO Station is leaving the net. QNP Unable to copy you. Unable to copy _____. QNQ* Move frequency to _____ and wait for _____ to finish handling traffic. Then send hom traffic for ______. QNR Answer _____ and receive traffic. QNS* Following stations are in the net. (Follow with list) or Request list of stations on the net. (If not ncs) QNT I request permission to leave the net for ____ minutes. QNU* The net has traffic for you. Stand by. QNV* Establish contact with _____ on this frequency. If successful, move to _____ and send him traffic for ______. QNW How do I route messages for ____? QNX You are excused from the net. (when used by ncs) Request to be excused from the net. (when used by a net station) QNY* Shift to another frequency (or to ______KHz) to clear traffic with _____. QNZ Zero beat your signal with mine.
The above two Q code lists, along with some other important information for traffic handlers, may be found on the ARRL web site as FSD-218.