Q code
The Q code is a standardized collection of three-letter message encodings, also known as a brevity code, all of which start with the letter "Q", initially developed for commercial radiotelegraph communication, and later adopted by other radio services, especially amateur radio. Although Q codes were created when radio used Morse code exclusively, they continued to be employed after the introduction of voice transmissions. To avoid confusion, transmitter call signs are restricted; while an embedded three-letter Q sequence may occur (for instance when requested by an amateur radio station dedicated to low-power operation), no country is ever issued an ITU prefix starting with "Q". The codes in the range QAA–QNZ are reserved for aeronautical use; QOA–QQZ for maritime use and QRA–QUZ for all services.
Early developments
The original Q codes were created, circa 1909, by the British government as a "list of abbreviations... prepared for the use of British ships and coast stations licensed by the Postmaster General". The Q codes facilitated communication between maritime radio operators speaking different languages, so they were soon adopted internationally. A total of forty-five Q codes appeared in the "List of Abbreviations to be used in Radio Communications", which was included in the Service Regulations affixed to the Third International Radiotelegraph Convention in London (The Convention was signed on July 5, 1912, and became effective July 1, 1913.)
- Q code means - three words essential Question code: example "QRN" - Question for the Reference of the Radio Network, atmospherics noise: noise from the natural resource, Atmospheric,Geological activity and Cosmic noise. It would affect the Radio Communication by the quality of the Signal/Noise ratio
The following table reviews a sample of the all-services Q codes adopted by the 1912 Convention:
| Code | Question | Answer or Notice |
|---|---|---|
| QRA | What ship or coast station is that? | This is ____. |
| QRB | What is your distance? | My distance is ____. |
| QRC | What is your true bearing? | My true bearing is ____ degrees. |
| QRD | Where are you bound for? | I am bound for ____. |
| QRF | Where are you bound from? | I am bound from ____. |
| QRG | What line do you belong to? | I belong to the ____ Line. |
| QRH | What is your wavelength in meters? | My wavelength is ____ meters. |
| QRJ | How many words have you to send? | I have ____ words to send. |
| QRK | How do you receive me? | I am receiving (1–5) where 1 is unreadable and 5 is perfect. |
| QRL | Are you busy? | I am busy. |
| QRM | Are you being interfered with? | I am being interfered with. |
| QRN | Are the atmospherics strong? | Atmospherics (noise) are very strong. |
Later usage
Over the years the original Q codes were modified to reflect changes in radio practice. For example, QSW/QSX originally stood for, "Shall I increase/decrease my spark frequency?", but in the 1920s, spark-gap transmitters were banned in the United States, rendering that meaning obsolete. By the 1970s, the Post Office Handbook for Radio Operators listed over a hundred Q codes, covering a wide range of subjects including radio procedures, meteorology, radio direction finding, and search and rescue.
Some Q codes are also used in aviation, in particular QNE, QNH and QFE, referring to certain altimeter settings. These codes are used in radiotelephone conversations with air traffic control as unambiguous shorthand, where safety and efficiency are of vital importance. A subset of Q codes is used by the Miami-Dade County, Florida local government for law enforcement and fire rescue communications, one of the few instances where Q codes are used in ground voice communication.[1]
The QAA–QNZ code range includes phrases applicable primarily to the aeronautical service,[2] as defined by the International Civil Aviation Organisation.[3] The QOA–QQZ code range is reserved for the maritime service. The QRA–QUZ code range includes phrases applicable to all services and is allocated to the International Telecommunications Union.[4] QVA–QZZ are not allocated.[5] Many codes have no immediate applicability outside one individual service, such as maritime operation (many QO or QU series codes) or radioteletype operation (the QJ series).[6]
Many military and other organizations that use Morse code have adopted additional codes, including the Z code used by most European and NATO countries. The Z code adds commands and questions adapted for military radio transmissions, for example, "ZBW 2", which means "change to backup frequency number 2", and "ZNB abc", which means "my checksum is abc, what is yours?"[7]
Used in their formal "question/answer" sense, the meaning of a Q code varies depending on whether or not the individual Q code is sent as a question or an answer. For example, the message "QRP?" means "Shall I decrease transmitter power?", and a reply of "QRP" means "Yes, decrease your transmitter power", whereas an unprompted statement "QRP" means "Please decrease your transmitter power". This structured use of Q codes is fairly rare and now mainly limited to amateur radio and military Morse code (CW) traffic networks.
Breakdown by service
- QAA to QNZ – Assigned by the International Civil Aviation Organization (ICAO).
- QOA to QQZ – For the Maritime Mobile Service.
- QRA to QUZ – Assigned by the International Telecommunications Union Radiocommunication Sector (ITU-R).
- QN- - The ARRL has also developed its own codes for message handling located in this range. Even though they overlap with other signals, they determined that their exclusive use in NTS nets limits confusion.
Aeronautical Code signals (QAA–QNZ; ICAO)
First defined in ICAO publication "Doc 6100-COM/504/1" and in "ICAO Procedures for Air Navigation Services, Abbreviations and Codes (PANS-ABC)" [Doc8400-4] (4th edition 1989), the majority of the Q codes have slipped out of common use; for example today reports such as QAU ("I am about to jettison fuel") and QAZ ("I am flying in a storm") would be voice or computerized transmissions. But several remain part of the standard ICAO radiotelephony phraseology in aviation. These are also part of ACP131, which lists all ITU-R Q Codes, without grouping them by aeronautical/marine/general use.
| Question ? | Answer or Advice | |
|---|---|---|
| QAB | May I have clearance (for ...) from ... (place) to ... (place) at flight level/altitude ... ? | You are cleared (or ... is cleared) by ... from ... (place) to ... (place) at flight level/altitude ... |
| QAF | Will you advise me when you are (were) at (over) ... (place)? | I am (was) at (over) ... (place) (at ... hours) at flight level/altitude ... |
| QAG | Arrange your flight in order to arrive over ... (place) at ... hours. or | |
| QAH | What is your height above ... (datum)? | I am at .... flight level/altitude ... or |
| QAI | What is the essential traffic respecting my aircraft? | The essential traffic respecting your aircraft is ... |
| QAK | Is there any risk of collision? | There is risk of collision. |
| QAL | Are you going to land at ... (place)? or |
I am going to land at ... (place). or |
| QAM | What is the latest available meteorological observation for ... (place)? | Meteorological observation made at ... (place) at ... hours was as follows ... Note.- The information may be given in Q Code form or the METAR form. |
| QAN | What is the surface wind direction and speed at ... (place)? | The surface wind direction and speed at ... (place) at ... hours is ... (direction) ... (speed). |
| QAO | What is the wind direction in degrees TRUE and speed at ... (position or zone/s) at each of the ... (figures) ... (units) levels above ... (datum)? | The wind direction and speed at (position or zone/s) at flight level/altitude ... is: ... (vertical distance) ... degrees TRUE ... (speed). |
| QAP | Shall I listen for you (or for ...) on ... kHz (... MHz)? | Listen for me (or for ...) on ... kHz (... MHz). |
| QAQ | Am I near a prohibited, restricted or danger area? or |
You are ... 1) near 2) flying within area ... (identification of area). |
| QAR | May I stop listening on the watch frequency for ... minutes? | You may stop listening on the watch frequency for ... minutes. |
| QAU | Where may I jettison fuel? | I am about to jettison fuel. or |
| QAW | I am about to carry out overshoot procedure. | |
| QAY | Will you advise me when you pass (passed) ... (place) bearing 090 (270) degrees relative to your heading? | I passed ... (place) bearing ... degrees relative to my heading at ... hours. |
| QAZ | Are you experiencing communication difficulties through flying in a storm? | I am experiencing communication difficulties through flying in a storm. |
| QBA | What is the horizontal visibility at ... (place)? | The horizontal visibility at ... (place) at ... hours is ... (distance figures and units). |
| QBB | What is the amount, type and height above official aerodrome elevation of the base of the cloud [at ... (place)]? | The amount, type and height above official aerodrome elevation of the base of the cloud at ... (place) at ... hours is: ... eights (... type) at ... (figures and units) height above official aerodrome elevation. |
| QBC | Report meteorological conditions as observed from your aircraft [at ... (position or zone)] [(at ... hours)]. | The meteorological conditions as observed from my aircraft at ... (position or zone) at ... hours at ... (figures and units) height above ... (datum) are ... Note.-The answer is required in the format of an AIREP message. |
| QBD | How much fuel have you remaining (expressed as hours and/or minutes of consumption)? | My fuel endurance is ... (hours and/or minutes). |
| QBE | I am about to wind in my aerial. | |
| QBF | Are you flying in cloud? | I am flying in cloud at ... flight level/altitude ... [and I am ascending (descending) to flight level/altitude ...]. |
| QBG | Are you flying above cloud? | I am flying above cloud and at flight level/altitude ... or |
| QBH | Are you flying below cloud? | I am flying below cloud and at flight level/altitude ... or |
| QBI | Is flight under IFR compulsory at ... (place) [or from ... to ... (place)]? | Flight under IFR is compulsory at ... (place) [or from ... to ... (place)]. |
| QBJ | What is the amount, type and height above ... (datum) of the top of the cloud [at ... (position or zone)]? | At ... hours at ... (position or zone) the top of the cloud is: amount ... eights (... type) at ... (figures and units) height above ... (datum). |
| QBK | Are you flying with no cloud in your vicinity? | I am flying with no cloud in my vicinity and at flight level/altitude ... |
| QBM | Has ... sent any messages for me? | Here is the message sent by ... at ... hours. |
| QBN | Are you flying between two layers of cloud? | I am flying between two layers of cloud and at flight level/altitude ... |
| QBO | What is the nearest aerodrome at which flight under VFR is permissible and which would be suitable for my landing? | Flying under VFR is permissible at ... (place) which would be suitable for your landing. |
| QBP | Are you flying in and out of cloud? | I am flying in and out of cloud and at flight level/altitude ... |
| QBS | Ascend (or descend) to ... (figures and units) height above ... (datum) before encountering instrument meteorological conditions or if visibility falls below ... (distance figures and units) and advise. | |
| QBT | What is the runway visual range at ... (place)? | The runway visual range at ... (place) at ... hours is ... (distance figures and units). |
| QBV | Have you reached flight level/altitude ... [or ... (area or place)]? | I have reached ... flight level/altitude ... [or ... (area or place)]. or |
| QBX | Have you left ... flight level/altitude ... [or ... (area or place)]? | I have left ... flight level/altitude ... [or ... (area or place)]. or |
| QBZ | Report your flying conditions in relation to clouds. | The reply to QBZ ? is given by the appropriate answer form of signals QBF, QBG, QBH, QBK, QBN and QBP. |
| QCA | May I change my flight level/altitude from ... to ... ? | You may change your flight level/altitude from ... to ... or |
| QCB | Delay is being caused by ... 1) your transmitting out of turn. 2) your slowness in answering. 3) lack of your reply to my ... | |
| QCE | When may I expect approach clearance? | Expect approach clearance at ... hours. or |
| QCF | Delay indefinite. Expect approach clearance not later than ... hours. | |
| QCH | May I taxi to ... (place)? | Cleared to taxi to ... (place). |
| QCI | Make a 360-degree turn immediately (turning to the ...). or | |
| QCS | My reception on ... frequency has broken down. | |
| QCX | What is your full call sign? | My full call sign is ... or |
| QCY | I am working on a trailing aerial. or | |
| QDB | Have you sent message ... to ... ? | I have sent message ... to ... |
| QDF | What is your D-Value at ... (position)? or |
My D-Value at ... (position) at ... (figures and units) height above the 1013.2 millibars datum is ... (D-Value figures and units) ... (specify plus or minus). or |
| QDL | Do you intend to ask me for a series of bearings? | I intend to ask you for a series of bearings. |
| QDM | Will you indicate the MAGNETIC heading for me to steer towards you (or ...) with no wind? | The MAGNETIC heading for you to steer to reach me (or ...) with no wind was ... degrees (at ... hours). |
| QDP | Will you accept control (or responsibility) of (for) ... now (or at ... hours)? | I will accept control (or responsibility) of (for) ... now (or at ... hours). |
| QDR | What is my MAGNETIC bearing from you (or from ...)? | Your MAGNETIC bearing from me (or from ...) was ... degrees (at ... hours). |
| QDT | Are you flying in visual meteorological condition? | I am flying in visual meteorological condition. or |
| QDU | Cancelling my IFR flight. or | |
| QDV | Are you flying in a flight visibility of less than ... (figures and units)? | I am flying in a flight visibility of less than ... (figures and units) at flight level/altitude ... |
| QEA | May I cross the runway ahead of me? | You may cross the runway ahead of you. |
| QEB | May I turn at the intersection? | Taxi as follows at the intersection ... (straight ahead DRT turn left LEFT turn right RITE). |
| QEC | May I make a 180-degree turn and return down the runway? | You may make a 180-degree turn and return down the runway. |
| QED | Shall I follow the pilot vehicle? | Follow the pilot vehicle. |
| QEF | Have I reached my parking area? or |
You have reached your parking area. or |
| QEG | May I leave the parking area? or |
You may leave the parking area. or |
| QEH | May I move to the holding position for runway number ... ? or |
Cleared to the holding position for runway number ... or |
| QEJ | May I assume position for take-off? or |
Cleared to hold at take-off position for runway number ... or |
| QEK | Are you ready for immediate take-off? | I am ready for immediate take-off. |
| QEL | May I take-off (and make a ... hand turn after take-off)? | You are cleared to take-off (turn as follows after take-off ...). |
| QEM | What is the condition of the landing surface at ... (place)? | The condition of the landing surface at ... (place) is ... Note.- The information is given by sending appropriate NOTAM Code groups. |
| QEN | Shall I hold my position? | Hold your position |
| QEO | Shall I clear the runway (or landing area)? or |
Clear the runway (or landing area). or |
| QES | Is a right-hand circuit in force at ... (place)? | A right-hand circuit is in force at ... (place). |
| QFA | What is the meteorological forecast for ... (flight, route, section of route or zone) for the period ... hours until ... hours? | The meteorological forecast for ... (flight, route, section of route or zone) for the period ... hours until ... hours is ... |
| QFB | The ... 1) approach 2) runway 3) approach and runway lights are out of order. | |
| QFC | What is the amount, the type and the height above ... (datum) of the base of the cloud at ... (place, position or zone)? | At ... (place, position or zone) the base of the cloud is ... eighths ... type at ... (figures and units) height above ... (datum). |
| QFD | 1) Is the ... visual beacon [at ... (place)] in operation? 2) Will you switch on the ... visual beacon [at ... (place)]? 3) Will you extinguish the aerodrome visual beacon [at ... (place)] until I have landed? |
1) The ... visual beacon [at ... (place)] is in operation 2) I will extinguish the aerodrome visual beacon [at ... (place)] until your landing is completed. |
| QFE | What should I set on the subscale of my altimeter so that the instrument would indicate its height above the reference elevation being used? | If you set the subscale of your altimeter to read ... millibars, the instrument would indicate its height above aerodrome elevation (above threshold, runway number ...). |
| QFF | [At ... (place)] what is the present atmospheric pressure converted to mean sea level in accordance with meteorological practice? | At ... (place) the atmospheric pressure converted to mean sea level in accordance with meteorological practice is (or was determined at ... hours to be) ... millibars. |
| QFG | Am I overhead? | You are overhead. |
| QFH | May I descend below the clouds? | You may descend below the clouds. |
| QFI | Are the aerodrome lights lit? | The aerodrome lights are lit. or |
| QFL | Will you send up pyrotechnical lights? | I will send up pyrotechnical lights. |
| QFM | What flight level/altitude ... 1) should I maintain? 2) are you maintaining? 3) do you intend cruising at? |
... 1) Maintain (or fly at) flight level/altitude ... |
| QFO | May I land immediately? | You may land immediately. |
| QFP | Will you give me the latest information concerning ... facility [at ... (place)]? | The latest information concerning ... facility [at ... (place)] is as follows ... Note.- The information is given by sending appropriate NOTAM Code groups. |
| QFQ | Are the approach and runway lights lit? | The approach and runway lights are lit. or |
| QFR | Does my landing gear appear damaged? | Your landing gear appears damaged. |
| QFS | Is the radio facility at ... (place) in operation? | The radio facility at ... (place) is in operation (or will be in operation in ... hours). or |
| QFT | Between what heights above ... (datum) has ice formation been observed [at ... (position or zone)]? | Ice formation has been observed at ... (position or zone) in the type of ... and with an accretion rate of ... between ... (figures and units) and ... (figures and units) heights above ... (datum). |
| QFU | What is the magnetic direction (or number) of the runway to be used? | The magnetic direction (or number) of the runway to be used is ... Note.- The runway number is indicated by a two-figure group and the magnetic direction by a three-figure group. |
| QFV | Are the floodlights switched on? | The floodlights are switched on. or |
| QFW | What is the length of the runway in use in ... (units)? | The length of runway ... now in use is ... (figures and units). |
| QFX | I am working (or am going to work) on a fixed aerial. or | |
| QFY | Please report the present meteorological landing conditions [at ... (place)]. | The present meteorological landing conditions at ... (place) are ... Note.- When given in Q Code the information is sent in the following sequence: QAN, QBA, QNY, QBB, QNH and/or QFE and, if necessary, QMU, QNT, QBJ. |
| QFZ | What is the aerodrome meteorological forecast for ... (place) for the period ... hours until ... hours? | The aerodrome meteorological forecast for ... (place) for the period ... hours until ... hours is ... Note.- When given in Q Code the following sequence of Q signal answer (or advice) forms is to be used: QAN, QBA, QNY, QBB and, if necessary, QMU, QNT and QBJ. |
| QGC | There are obstructions to the ... of ... runway ... | |
| QGD | Are there on my track any obstructions whose elevation equals or exceeds my altitude? | There are obstructions on your track ... (figures and units) height above ... (datum). |
| QGE | What is my distance to your station (or to ...)? | Your distance to my station (or to ...) is ... (distance figures and units). |
| QGH | May I land using ... (procedure or facility)? | You may land using ... (procedure or facility). |
| QGK | What track should I make good? or |
Make good a track from ... (place) on ... degrees ... (true or magnetic). or |
| QGL | May I enter the ... (control area or zone) at ... (place)? | You may enter the ... (control area or zone) at ... (place). |
| QGM | Leave the ... (control area or zone). | |
| QGN | May I be cleared to land [at ... (place)]? | You are cleared to land [at ... (place)]. |
| QGO | Landing is prohibited at ... (place). | |
| QGP | What is my number for landing? | You are number ... to land. |
| QGQ | May I hold at ... (place)? | Hold at ... (place) at flight level/altitude ... (datum) and await further clearance. |
| QGT | Fly for ... minutes on a heading what will enable you to maintain a track reciprocal to your present one. | |
| QGU | Fly for ... minutes on a magnetic heading of ... degrees. | |
| QGV | Do you see me? or |
I see you at ... (cardinal or quadrantal point of direction). or |
| QGW | Does my landing gear appear to be down and in place? | Your landing gear appears to be down and in place. |
| QGZ | Hold on ... direction of ... facility. | |
| QHE | Will you inform me when you are on ... leg of approach? | I am on ... 1) cross-wind leg 2) down-wind leg 3) base leg 4) final leg ... of approach. |
| QHG | May I enter traffic circuit at flight level/altitude ...? | Cleared to enter traffic circuit at flight level/altitude ... |
| QHH | Are you making an emergency landing? | I am making an emergency landing. or |
| QHI | Are you (or is ...) ... 1) waterborne? 2) on land? |
I am (or ... is) ... 1) waterborne 2) on land at ... hours. |
| QHQ | May I make a ... approach [at ... (place)]? or |
You may make a ... approach [at ... (place)]. or |
| QHZ | Shall I circle the aerodrome (or go around)? | Circle the aerodrome (or go around). |
| QIC | May I establish communication with ... radio station on ... kHz (or ... MHz.) now (or at ... hours)? | Establish communication with ... radio station on ... kHz. (or MHz.) now (or at ...hours). or |
| QIF | What frequency is ... using? | ... is using ... kHz (or ... MHz.). |
| QJA | Is my ... 1) tape 2) mark and space reversed? |
Your ... 1) tape 2) mark and space is reversed. |
| QJB | Will you use ... 1) radio? 2) cable? 3) telegraph? 4) teletypewriter? 5) telephone? 6) receiver? 7) transmitter? 8) reperforator? |
I will use ... 1) radio. 2) cable. 3) telegraph. 4) teletypewriter. 5) telephone. 6) receiver. 7) transmitter. 8) reperforator. |
| QJC | Will you check your ... 1) transmitter distributor? 2) auto-head? 3) perforator? 4) reperforator? 5) printer? 6) printer motor? 7) keyboard? 8) antenna system? |
I will check my ... 1) transmitter distributor. 2) auto-head. 3) perforator. 4) reperforator. 5) printer. 6) printer motor. 7) keyboard. 8) antenna system. |
| QJD | Am I transmitting ... 1) in letters? 2) in figures? |
You are transmitting ... 1) in letters 2) in figures. |
| QJE | Is my frequency shift ... 1) too wide? 2) too narrow? 3) correct? |
Your frequency shift is ... 1) too wide. 2) too narrow (by ... cycles). 3) correct. |
| QJF | My signal as checked by monitor ... is satisfactory ... 1) locally. 2) as radiated. | |
| QJG | Shall I revert to automatic relay? | Revert to automatic relay. |
| QJH | Shall I run ... 1) my test tape? 2) a test sentence? |
Run ... 1) your test tape. 2) a test sentence. |
| QJI | Will you transmit a continuous ... 1) mark? 2) space? |
I am transmitting a continuous... 1) mark. 2) space. |
| QJK | Are you receiving ... 1) a continuous mark? 2) a continuous space? 3) a mark bias? 4) a space bias? |
I am receiving ... 1) a continuous mark. 2) a continuous space. 3) a mark bias. 4) a space bias. |
| QKC | The sea conditions (at ... position) ... 1) permit alighting but not take-off. 2) render alighting extremely hazardous. | |
| QKF | May I be relieved (at ... hours)? | You may expect to be relieved at ... hours [by ... 1) aircraft ... (identification) (type ...) 2) vessel whose call sign is ... (call sign) {and/or whose name is ... (name)}]. |
| QKG | Will relief take place when ... (identification) establishes ... 1) visual, 2) communications, contact with survivors? |
Relief will take place when ... (identification) establishes ... 1) visual, 2) communications, contact with survivors. |
| QKH | Report details of the parallel sweep (track) search being (or to be) conducted? or |
The parallel sweep (track) search is being (or to be) conducted ... 1) with direction of sweeps ... degrees ... (true or magnetic). |
| QKN | Aircraft plotted (believed to be you) in position ... on track ... degrees at ... hours. | |
| QKO | What other units are (or will be) taking part in the operation [... (identification of operation)]? | In the operation [... (identification)], the following units are (or will be) taking part ... (name of units). or |
| QKP | Which pattern of search is being followed? | The search pattern is ... 1) parallel sweep. 2) square search. 3) creeping line ahead. 4) track crawl. 5) contour search. 6) combined search by aircraft and ship. 7) ... (specify). |
| QLB | Will you monitor ... station and report regarding range, quality, etc.? | I have monitored ... station and report (briefly) as follows ... |
| QLH | Will you use simultaneous keying on ... frequency and ... frequency? | I will now key simultaneously on ... frequency and ... frequency. |
| QLV | Is the ... radio facility still required? | The ... radio facility is still required. |
| QMH | Shift to transmit and receive on ... kHz (or ... MHz.); if communication is not established within 5 minutes, revert to present frequency. | |
| QMI | Report the vertical distribution of cloud [at ... (position or zone)] as observed from your aircraft. | The vertical distribution of cloud as observed from my aircraft at ... hours at ... (position or zone) is : lowest layer observed* ... eights (... type) with base of ... (figures and units) and tops of ... (figures and units) |
| QMU | What is the surface temperature at ... (place) and what is the dew point temperature at that place? | The surface temperature at ... (place) at ... hours is ... degrees and the dew point temperature at that time and place is ... degrees. |
| QMW | At ... (position or zone) what is (are) the flight level(s)/altitude(s) ... of the zero Celsius isotherm(s)? | At ... (position or zone) the zero Celsius isotherm(s) is (are) at flight level(s)/altitude(s) ... |
| QMX | What is the air temperature [at ... (position or zone)] (at ... hours) at flight level/altitude ...? | At ... (position or zone) at ... hours the air temperature is ... (degrees and units) at flight level/altitude ... Note.- Aircraft reporting QMX information will transmit the temperature figures as corrected for airspeed. |
| QMZ | Have you any amendments to the flight forecast in respect of section of route yet to be traversed? | The following amendment(s) should be made to the flight forecast ... [If no amendments, signal QMZ NIL] |
| QNE | What indication will my altimeter give on landing at ... (place) at ... hours, my sub-scale being set to 1013.2 millibars (29.92 inches)? | On landing at ... (place) at ... hours, with your sub-scale being set to 1013.2 millibars (29.92 inches), your altimeter will indicate ... (figures and units). |
| QNH | What should I set on the subscale of my altimeter so that the instrument would indicate its elevation if my aircraft were on the ground at your station? | If you set the subscale of your altimeter to read ... millibars, the instrument would indicate its elevation if your aircraft were on the ground at my station at ... hours. Note.- When the setting is given in hundredths of inch the abbreviation INS is used to identify the units. |
| QNI | Between what heights above ... (datum) has turbulence been observed at ... (position or zone)? | Turblence has been observed at ... (position or zone) with an intensity of ... between ... (figures and units) and ... (figures and units) heights above ... (datum). |
| QNO | I am not equipped to give the information (or provide the facility) requested. | |
| QNR | I am approaching my point of no return. | |
| QNT | What is the maximum speed of the surface wind at ... (place)? | The maximum speed of the surface wind at ... (place) at ... hours is ... (speed figures and units). |
| QNY | What is the present weather and the intensity thereof at ... (place, position or zone)? | The present weather and intensity thereof at ... (place, position or zone) at ... hours is ... Notes: |
Maritime Mobile Service (QOA–QQZ)
Main article Maritime Mobile Service Q Codes
This assignment is specified in RECOMMENDATION ITU-R M.1172.[9]
Q signals are not substantially used in the maritime service. Morse code is now very rarely used for maritime communications, but in isolated maritime regions like Antarctica and the South Pacific the use of Q Codes continues. Q Codes still work when HF voice circuits are not possible due to atmospherics and the nearest vessel is one ionospheric hop away.
| Question ? | Answer or Advice | |
|---|---|---|
| QOA | Can you communicate by radiotelegraphy (500 kHz)? | I can communicate by radiotelegraphy (500 kHz). |
| QOB | Can you communicate by radiotelephony (2182 kHz)? | I can communicate by radiotelephony (2182 kHz). |
| QOC | Can you communicate by radiotelephony (channel 16 - frequency 156.80 MHz)? | I can communicate by radiotelephony (channel 16 - frequency 156.80 MHz). |
| QOD | Can you communicate with me in ... 0. Dutch 5. Italian 1. English 6. Japanese 2. French 7. Norwegian 3. German 8. Russian 4. Greek 9. Spanish? |
I can communicate with you in ... 0. Dutch 5. Italian 1. English 6. Japanese 2. French 7. Norwegian 3. German 8. Russian 4. Greek 9. Spanish. |
| QOE | Have you received the safety signal sent by ... (name and/or call sign)? | I have received the safety signal sent by ... (name and/or call sign). |
| QOF | What is the commercial quality of my signals? | The quality of your signals is ... 1. not commercial 2. marginally commercial 3. commercial. |
| QOG | How many tapes have you to send? | I have ... tapes to send. |
| QOH | Shall I send a phasing signal for ... seconds? | Send a phasing signal for ... seconds. |
| QOI | Shall I send my tape? | Send your tape. |
| QOJ | Will you listen on ... kHz (or MHz) for signals of emergency position-indicating radiobeacons? | I am listening on ... kHz (or MHz) for signals of emergency position-indicating radiobeacons. |
| QOK | Have you received the signals of an emergency position-indicating radiobeacon on ... kHz (or MHz)? | I have received the signals of an emergency position-indicating radiobeacon on ... kHz (or MHz). |
| QOL | Is your vessel fitted for reception of selective calls? If so, what is your selective call number or signal? | My vessel is fitted for the reception of selective calls. My selective call number or signal is ... |
| QOM | On what frequencies can your vessel be reached by a selective call? | My vessel can be reached by a selective call on the following frequency/ies ... (periods of time to be added if necessary). |
| QOO | Can you send on any working frequency? | I can send on any working frequency. |
| QOT | Do you hear my call; what is the approximate delay in minutes before we may exchange traffic? | I hear your call; the approximate delay is ... minutes. |
All Services (QRA–QUZ)
First defined by the Washington 1927 ITU Radio Regulations. Later defined by ITU-R in Appendix 9 to the Radio Regulations Annex to the International Telecommunications Convention (Atlantic City) 1947. The current callsign table is found in ITU-R Appendix 42. Current interpretation of the Q-code can be found in ITU-R Appendices 14 and 15.
ITU Radio Regulations 1990, Appendix 13: Miscellaneous Abbreviations and Signals to Be Used in Radiotelegraphy Communications Except in the Maritime Mobile Service
| Question ? | Answer or Advice | |
|---|---|---|
| QRA | What is the name of your vessel (or station)? | The name of my vessel (or station) is ... |
| QRB | How far approximately are you from my station? | The approximate distance between our stations is ... nautical miles (or km). |
| QRC | By what private enterprise (or state administration) are the accounts for charges for your station settled? | The accounts for charges of my station are settled by the private enterprise ... (or state administration). |
| QRD | Where are you bound for and where are you from? | I am bound for ... from ... |
| QRE | What is your estimated time of arrival at ... (or over ...) (place)? | My estimated time of arrival at ... (or over ...) (place) is ... hours. |
| QRF | Are you returning to ... (place)? | I am returning to ... (place). or |
| QRG | Will you tell me my exact frequency (or that of ...)? | Your exact frequency (or that of ...) is ... kHz (or MHz). |
| QRH | Does my frequency vary? | Your frequency varies. |
| QRI | How is the tone of my transmission? | The tone of your transmission is ... 1. good 2. variable 3. bad. |
| QRJ | How many radiotelephone calls have you to book? | I have ... radiotelephone calls to book. |
| QRK | What is the intelligibility of my signals (or those of ...)? | The intelligibility of your signals (or those of ...) is ... 1. bad 2. poor 3. fair 4. good 5. excellent. |
| QRL | Are you busy? | I am busy (or I am busy with ...). Please do not interfere. |
| QRM | Are you being interfered with? [AP13] or |
I am being interfered with [AP13] or |
| QRN | Are you troubled by static? | I am troubled by static (1. nil 2. slightly 3. moderately 4. severely 5. extremely). |
| QRO | Shall I increase transmitter power? | Increase transmitter power. |
| QRP | Shall I decrease transmitter power? | Decrease transmitter power. |
| QRQ | Shall I send faster? | Send faster (... words per minute). |
| QRR | Are you ready for automatic operation? | I am ready for automatic operation. Send at ... words per minute. |
| QRS | Shall I send more slowly? | Send more slowly (... words per minute). |
| QRT | Shall I stop sending? | Stop sending. |
| QRU | Have you anything for me? | I have nothing for you. |
| QRV | Are you ready? | I am ready. |
| QRW | Shall I inform ... that you are calling him on ... kHz (or MHz)? | Please inform ... that I am calling him on ... kHz (or MHz). |
| QRX | When will you call me again? | I will call you again at ... hours (on ... kHz (or MHz)). |
| QRY | What is my turn? (Relates to communication). |
Your turn is Number ... (or according to any other indication). (Relates to communication). |
| QRZ | Who is calling me? | You are being called by ... (on ... kHz (or MHz)). |
| QSA | What is the strength of my signals (or those of ...)? | The strength of your signals (or those of ...) is 1. scarcely perceptible 2. weak 3. fairly good 4. good 5. very good. |
| QSB | Are my signals fading? | Your signals are fading. |
| QSC | Are you a cargo vessel? [AP13] or |
I am a cargo vessel. [AP13] or |
| QSD | Is my keying defective? [AP13] or |
Your keying is defective. [AP13] or |
| QSE* | What is the estimated drift of the survival craft? | The estimated drift of the survival craft is ... (figures and units). |
| QSF* | Have you effected rescue? | I have effected rescue and am proceeding to ... base (with ... persons injured requiring ambulance). |
| QSG | Shall I send ... telegrams at a time? | Send ... telegrams at a time. |
| QSH | Are you able to home on your direction-finding equipment? | I am able to home on my D/F equipment (on station ...). |
| QSI | I have been unable to break in on your transmission. or | |
| QSJ | What is the charge to be collected to ... including your internal charge? | The charge to be collected to ... including my internal charge is ... francs. |
| QSK | Can you hear me between your signals and if so can I break in on your transmission? | I can hear you between my signals; break in on my transmission. |
| QSL | Can you acknowledge receipt? | I am acknowledging receipt. |
| QSM | Shall I repeat the last telegram which I sent you (or some previous telegram)? | Repeat the last telegram which you sent me (or telegram(s) number(s) ...). |
| QSN | Did you hear me (or ... (call sign)) on ... kHz (or MHz)? | I did hear you (or ... (call sign)) on ... kHz (or MHz). |
| QSO | Can you communicate with ... direct (or by relay)? | I can communicate with ... direct (or by relay through ...). |
| QSP | Will you relay to ... free of charge? | I will relay to ... free of charge. |
| QSQ | Have you a doctor on board (or is ... (name of person) on board)? | I have a doctor on board (or ... (name of person) is on board). |
| QSR | Shall I repeat the call on the calling frequency? | Repeat your call on the calling frequency; did not hear you (or have interference). |
| QSS | What working frequency will you use? | I will use the working frequency ... kHz (or MHz) (in the HF bands normally only the last three figures of the frequency need be given). |
| QSU | Shall I send or reply on this frequency (or on ... kHz (or MHz)) (with emissions of class ...)? | Send or reply on this frequency (or on ... kHz (or MHz)) (with emissions of class ...). |
| QSV | Shall I send a series of Vs on this frequency (or on ... kHz (or MHz))? | Send a series of Vs on this frequency (or on ... kHz (or MHz)). |
| QSW | Will you send on this frequency (or on ... kHz (or MHz)) (with emissions of class ...)? | I am going to send on this frequency (or on ... kHz (or MHz)) (with emissions of class ...). |
| QSX | Will you listen to ... (call sign(s)) on ... kHz (or MHz)? [AP13] or |
I am listening to ... (call sign(s)) on ... kHz (or MHz). [AP13] or |
| QSY | Shall I change to transmission on another frequency? | Change to transmission on another frequency (or on ... kHz (or MHz)). |
| QSZ | Shall I send each word or group more than once? | Send each word or group twice (or ... times). |
| QTA | Shall I cancel telegram (or message) number ... ? | Cancel telegram (or message) number ... |
| QTB | Do you agree with my counting of words? | I do not agree with your counting of words; I will repeat the first letter or digit of each word or group. |
| QTC | How many telegrams have you to send? | I have ... telegrams for you (or for ...). |
| QTD* | What has the rescue vessel or rescue aircraft recovered? | ... (identification) has recovered ... 1. ... (number) survivors 2. wreckage 3. ... (number) bodies. |
| QTE | What is my TRUE bearing from you? or |
Your TRUE bearing from me is ... degrees at ... hours. or |
| QTF | Will you give me the position of my station according to the bearings taken by the direction-finding stations which you control? | The position of your station according to the bearings taken by the D/F stations which I control was ... latitude, ... longitude (or other indication of position), class ... at ... hours. |
| QTG | Will you send two dashes of ten seconds each followed by your call sign (repeated ... times) (on ... kHz (or MHz))? or |
I am going to send two dashes of ten seconds each followed by my call sign (repeated ... times) (on ... kHz (or MHz)). or |
| QTH | What is your position in latitude and longitude (or according to any other indication)? | My position is ... latitude, ... longitude (or according to any other indication). |
| QTI | What is your TRUE track? [AP13] | My TRUE track is ... degrees. [AP13] |
| QTI* | What is your TRUE course? [AP14] | My TRUE course is ... degrees. [AP14] |
| QTJ* | What is your speed? (Requests the speed of a ship or aircraft through the water or air respectively). |
My speed is ... knots (or ... kilometres per hour or ... statute miles per hour). (Indicates the speed of a ship or aircraft through the water or air respectively). |
| QTK* | What is the speed of your aircraft in relation to the surface of the Earth? | The speed of my aircraft in relation to the surface of the Earth is ... knots (or ... kilometres per hour or ... statute miles per hour). |
| QTL* | What is your TRUE heading? | My TRUE heading is ... degrees. |
| QTM* | What is your MAGNETIC heading? | My MAGNETIC heading is ... degrees. |
| QTN | At what time did you depart from ... (place)? | I departed from ... (place) at ... hours. |
| QTO | Have you left dock (or port)? or |
I have left dock (or port). or |
| QTP | Are you going to enter dock (or port)? or |
I am going to enter dock (or port). or |
| QTQ | Can you communicate with my station by means of the International Code of Signals (INTERCO)? | I am going to communicate with your station by means of the International Code of Signals (INTERCO). |
| QTR | What is the correct time? | The correct time is ... hours. |
| QTS | Will you send your call sign for tuning purposes or so that your frequency can be measured now (or at ... hours) on ... kHz (or MHz)? [AP13] or |
I will send my call sign for tuning purposes or so that my frequency may be measured now (or at ... hours) on ... kHz (or MHz). [AP13] or |
| QTT | The identification signal which follows is superimposed on another transmission. | |
| QTU | What are the hours during which your station is open? | My station is open from ... to ... hours. |
| QTV | Shall I stand guard for you on the frequency of ... kHz (or MHz) (from ... to ... hours)? | Stand guard for me on the frequency of ... kHz (or MHz) (from ... to ... hours). |
| QTW* | What is the condition of survivors? | Survivors are in ... condition and urgently need ... |
| QTX | Will you keep your station open for further communication with me until further notice (or until ... hours)? | I will keep my station open for further communication with you until further notice (or until ... hours). |
| QTY* | Are you proceeding to the position of incident and if so when do you expect to arrive? | I am proceeding to the position of incident and expect to arrive at ... hours (on ... (date)). |
| QTZ* | Are you continuing the search? | I am continuing the search for ... (aircraft, ship, survival craft, survivors or wreckage). |
| QUA | Have you news of ... (call sign)? | Here is news of ... (call sign). |
| QUB* | Can you give me in the following order information concerning: the direction in degrees TRUE and speed of the surface wind; visibility; present weather; and amount, type and height of base of cloud above surface elevation at ... (place of observation)? | Here is the information requested: ... (The units used for speed and distances should be indicated.) |
| QUC | What is the number (or other indication) of the last message you received from me (or from ... (call sign))? | The number (or other indication) of the last message I received from you (or from ... (call sign)) is ... |
| QUD | Have you received the urgency signal sent by ... (call sign of mobile station)? | I have received the urgency signal sent by ... (call sign of mobile station) at ... hours. |
| QUE | Can you use telephony in ... (language), with interpreter if necessary; if so, on what frequencies? [AP13] or |
I can use telephony in ... (language) on ... kHz (or MHz). [AP13] or |
| QUF | Have you received the distress signal sent by ... (call sign of mobile station)? | I have received the distress signal sent by ... (call sign of mobile station) at ... hours. |
| QUG | Will you be forced to alight (or land)? [AP13] | I am forced to alight (or land) immediately. or |
| QUH* | Will you give me the present barometric pressure at sea level? | The present barometric pressure at sea level is ... (units). |
| QUI | Are your navigation lights working? [AP13] | My navigation lights are working. [AP13] |
| QUJ | Will you indicate the TRUE track to reach you (or ...)? [AP13] | The TRUE track to reach me (or ...) is ... degrees at ... hours. [AP13] |
| QUK | Can you tell me the condition of the sea observed at ... (place or coordinates)? [AP13] | The sea at ... (place or coordinates) is ... [AP13] |
| QUL | Can you tell me the swell observed at ... (place or coordinates)? [AP13] | The swell at ... (place or coordinates) is ... [AP13] |
| QUM | May I resume normal working? | Normal working may be resumed. |
| QUN | 1. When directed to all stations: [AP13,14] Will vessels in my immediate vicinity ... |
My position, TRUE course and speed are ... |
| QUO* | Shall I search for ... 1. aircraft 2. ship 3. survival craft in the vicinity of ... latitude, ... longitude (or according to any other indication)? |
Please search for ... 1. aircraft 2. ship 3. survival craft in the vicinity of ... latitude, ... longitude (or according to any other indication). |
| QUP | Will you indicate your position by 1. searchlight 2. black smoke trail 3. pyrotechnic lights? |
My position is indicated by 1. searchlight 2. black smoke trail 3. pyrotechnic lights. |
| QUQ | Shall I train my searchlight nearly vertical on a cloud, occulting if possible and, if your aircraft is seen, deflect the beam up wind and on the water (or land) to facilitate your landing? | Please train your searchlight on a cloud, occulting if possible and, if my aircraft is seen or heard, deflect the beam up wind and on the water (or land) to facilitate my landing. [AP13] |
| QUR* | Have survivors ... 1. received survival equipment 2. been picked up by rescue vessel 3. been reached by ground rescue party? |
Survivors ... 1. are in possession of survival equipment dropped by ... 2. have been picked up by rescue vessel 3. have been reached by ground rescue party. |
| QUS* | Have you sighted survivors or wreckage? If so, in what position? | Have sighted ... 1. survivors in water 2. survivors on rafts 3. wreckage in position ... latitude, ... longitude (or according to any other indication). |
| QUT* | Is position of incident marked? | Position of incident is marked by ... 1. flame or smoke float 2. sea marker 3. sea marker dye 4. ... (specify other marking). |
| QUU* | Shall I home ship or aircraft to my position? | Home ship or aircraft ... (call sign) ... 1. to your position by transmitting your call sign and long dashes on ... kHz (or MHz) 2. by transmitting on ... kHz (or MHz) TRUE track to reach you. |
| QUW* | Are you in the search area designated as ... (designator or latitude and longitude)? | I am in the ... (designation) search area. |
| QUX | Do you have any navigational warnings or gale warnings in force? [AP14] | I have the following navigational warning(s) or gale warning(s) in force: ... [AP14] |
| QUY* | Is position of survival craft marked? | Position of survival craft was marked at ... hours by ... 1. flame or smoke float 2. sea marker 3. sea marker dye 4. ... (specify other marking). |
| QUZ | May I resume restricted working? [AP14] | Distress phase still in force; restricted working may be resumed. [AP14] |
Amateur radio
Amateur radio actually has adapted two different sets of Q codes for use in amateur communications. The first set 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.
The second set is the set of QN Signals, used only in ARRL NTS nets. These operating signals generally have no equivalent in the ACP 131 publication or ITU publications, and are specifically defined only for use in ARRL NTS nets. They are not used in casual amateur radio communications.[10][11]
Selected Q codes were soon adopted by amateur radio operators. In December 1915, the American Radio Relay League began publication of a magazine titled QST, named after the Q code for "General call to all stations". In amateur radio, the Q codes were originally used in Morse code transmissions to shorten lengthy phrases and were followed by a Morse code question mark (··— —··) if the phrase was a question.
Q codes are commonly used in voice communications as shorthand nouns, verbs, and adjectives making up phrases. For example, an amateur radio operator will complain about QRM (man-made interference), or tell another operator that there is "QSB on the signal" (fading); "to QSY" is to change your operating frequency, or to break in on a conversation QSK is often used even on VHF and UHF frequencies. (See also Informal usage, below.)
Q codes as adapted for use in amateur radio
| Code | Question | Answer or Statement |
|---|---|---|
| QLE | What is your expected signal? | The expected signal is low... |
| QNI | May I join the net? | You may check in... |
| QRA | What is the name (or call sign) of your station? | The name (or call sign) of my station is ... |
| QRG | Will you tell me my exact frequency (or that of ...)? | Your exact frequency (or that of ... ) is ... kHz (or MHz). |
| QRH | Does my frequency vary? | Your frequency varies. |
| QRI | How is the tone of my transmission? | The tone of your transmission is (1. Good; 2. Variable; 3. Bad) |
| QRJ | How many voice contacts do you want to make? | I want to make ... voice contacts. |
| QRK | What is the readability of my signals (or those of ...)? | The readability of your signals (or those of ...) is ... (1 to 5). |
| QRL | Are you busy? | I am busy. (or I am busy with ... ) Please do not interfere. |
| QRM | Do you have interference? [from other stations] | I have interference. |
| QRN | Are you troubled by static? | I am troubled by static. |
| QRO | Shall I increase power? | Increase power. |
| QRP | Shall I decrease power? | Decrease power. |
| QRQ | Shall I send faster? | Send faster (... wpm) |
| QRS | Shall I send more slowly? | Send more slowly (... wpm) |
| QRT | Shall I cease or suspend operation?/ shutoff the radio | I am suspending operation. /shutting off the radio |
| QRU | Have you anything for me? | I have nothing for you. |
| QRV | Are you ready? | I am ready. |
| QRW | Shall I inform ... that you are calling him on ... kHz (or MHz)? | Please inform ... that I am calling him on ... kHz (or MHz). |
| QRX | Shall I standby / When will you call me again? | Please standby / I will call you again at ... (hours) on ... kHz (or MHz) |
| QRZ | Who is calling me? | You are being called by ... on ... kHz (or MHz) |
| QSA | What is the strength of my signals (or those of ... )? | The strength of your signals (or those of ...) is ... (1 to 5). |
| QSB | Are my signals fading? | Your signals are fading. |
| QSD | Is my keying defective? | Your keying is defective. |
| QSG | Shall I send ... telegrams (messages) at a time? | Send ... telegrams (messages) at a time. |
| QSK | Can you hear me between your signals? | I can hear you between my signals. |
| QSL | Can you acknowledge receipt? | I am acknowledging receipt. |
| QSM | Shall I repeat the last telegram (message) which I sent you, or some previous telegram (message)? | Repeat the last telegram (message) which you sent me (or telegram(s) (message(s)) numbers(s) ...). |
| QSN | Did you hear me (or ... (call sign)) on .. kHz (or MHz)? | I did hear you (or ... (call sign)) on ... kHz (or MHz). |
| QSO | Can you communicate with ... direct or by relay? | I can communicate with ... direct (or by relay through ...). |
| QSP | Will you relay a message to ...? | I will relay a message to ... . |
| QSR | Do you want me to repeat my call? | Please repeat your call; I did not hear you. |
| QSS | What working frequency will you use? | I will use the working frequency ... kHz (or MHz). |
| QST | – | Here is a broadcast message to all amateurs. |
| QSU | Shall I send or reply on this frequency (or on ... kHz (or MHz))? | Send or reply on this frequency (or on ... kHz (or MHz)). |
| QSW | Will you send on this frequency (or on ... kHz (or MHz))? | I am going to send on this frequency (or on ... kHz (or MHz)). |
| QSX | Will you listen to ... (call sign(s) on ... kHz (or MHz))? | I am listening to ... (call sign(s) on ... kHz (or MHz)) |
| QSY | Shall I change to transmission on another frequency? | Change to transmission on another frequency (or on ... kHz (or MHz)). |
| QSZ | Shall I send each word or group more than once? | Send each word or group twice (or ... times). |
| QTA | Shall I cancel telegram (message) No. ... as if it had not been sent? | Cancel telegram (message) No. ... as if it had not been sent. |
| QTC | How many telegrams (messages) have you to send? | I have ... telegrams (messages) for you (or for ...). |
| QTH | What is your position in latitude and longitude (or according to any other indication)? | My position is ... latitude...longitude |
| QTR | What is the correct time? | The correct time is ... hours |
| QTU | At what times are you operating? | I am operating from ... to ... hours. |
| QTX | Will you keep your station open for further communication with me until further notice (or until ... hours)? | I will keep my station open for further communication with you until further notice (or until ... hours). |
| QUA | Have you news of ... (call sign)? | Here is news of ... (call sign). |
| QUC | What is the number (or other indication) of the last message you received from me (or from ... (call sign))? | The number (or other indication) of the last message I received from you (or from ... (call sign)) is ... |
| QUD | Have you received the urgency signal sent by ... (call sign of mobile station)? | I have received the urgency signal sent by ... (call sign of mobile station) at ... hours. |
| QUE | Can you speak in ... (language), – with interpreter if necessary; if so, on what frequencies? | I can speak in ... (language) on ... kHz (or MHz). |
| QUF | Have you received the distress signal sent by ... (call sign of mobile station)? | I have received the distress signal sent by ... (call sign of mobile station) at ... hours. |
Note : "KK" is often used at the end of a reply to a Q Code to mean "OK" or "Acknowledged". This practice predates amateur radio as telegraph operators in the late 19th Century are known to have used it.
Informal usage
QSK – "I can hear you during my transmission" – refers to a particular mode of Morse code operating in which the receiver is quickly enabled during the spaces between the dits and dahs, which allows another operator to interrupt transmissions. Many modern transceivers incorporate this function, sometimes referred to as full break-in as against semi-break-in in which there is a short delay before the transceiver goes to receive.[13]
QSY – "Change to transmission on another frequency"; colloquially, "move [=change address]". E.g., "When did GKB QSY from Northolt to Portishead....?"[14]
QTH – "My location is…"; colloquially in voice or writing, "location". E.g., "The OCF [antenna] is an interesting build but at my QTH a disappointing performer."[15]
German use during World War II
During World War II, according to Bletchley Park’s General Report on Tunny, [16] German radio teleprinter networks used Q-codes to establish and maintain circuit connections. In particular QKP was to indicate the Lorenz cipher machine setting for each message and QZZ to indicate that the daily key change was about to take place at the sender's station.
See also
- Z code
- ACP-131
- Ten-code
- Prosigns for Morse code
- International Code of Signals
- International maritime signal flags
References
- ↑ National Communications Magazine. Radio codes & signals – Florida. Retrieved 2010-01-30.
- ↑ The Q Code
- ↑ ICAO PANS (Procedures for Air Navigation Services) Doc 8400: The ICAO Q Code.
- ↑ http://www.globalsecurity.org/military/library/policy/navy/nrtc/14244_ch4.pdf
- ↑ www.portland-amateur-radio-club.org.uk – Web site hosted by Freeola.com
- ↑ http://kyalami.homeip.net/qcodes.htm
- ↑ ACP 131(E), Communications Instructions – Operating Signals, March 1997. Chapter 2 contains a full list of 'Q' codes
- ↑ "List of Q-codes".
- ↑ "RECOMMENDATION ITU-R M.1172".
- ↑ "Operating Signals".
- ↑ "FSD-218 - Field Service Form: Instructions for NTS Radiogram Messages" (PDF).
- ↑ "International Morse code Recommendation ITU-R M.1677-1". itu.int. International Telecommunication Union. October 2009. Retrieved 23 December 2011.
- ↑ "Communications Instructions Operating Signals" (PDF). Combined Communications-Electronics Board. April 2006. Retrieved 2014-05-16. External link in
|publisher=(help) - ↑ Post in the uk.radio.amateur newsgroup Dated 2010-08-21. Accessed 2013-08-04.
- ↑ Has anyone used a tuner with an Off Centre Fed Dipole? How well did it work? Article on Amateur Radio Wiki. Accessed 2013-08-04.
- ↑ http://www.alanturing.net/turing_archive/archive/t/t01/TR01-016.html ‘’General Report on Tunny’’ with Emphasis on Statistical Methods, pp.13-14
External links
- Easy to read Q Code graphic.
- Handbook for Wireless Telegraph Operators, October, 1909.
- Radio Laws and Regulations of the United States: Edition July 27, 1914. (Includes the 1912 London Radiotelegraphic Convention)
- List of Q codes
- A resource for Morse Code operation in the amateur radio hobby
- Amateur Radio Q Codes
- "Q-Signals"
- Radiotelegraph and Radiotelephone Codes, Prowords And Abbreviations
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