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====== A ======

  - In the UK and some other countries “**/A**” is added after the callsign if an operator is transmitting from a fixed location that is not their permanent location given in their licence. It is not taken as seriously as it used to be, and in practice you will probably never hear it.
  - **ATNO** is an All Time New One, and refers to the first time you contact a country on any frequency or mode. If you have worked the country before, but perhaps have never worked it in CW on 10 metres, you may want to get the station in your log even if there are hundreds of people calling them. Sometimes, DXpeditions will say they are specifically looking to give ATNOs towards the end of their time in the DX location in order to cut down the number of people calling them.
  - **Auroral propagation** is important on 6 metres and above. Signals sound fuzzy and indistinct, although SSB can be understood and CW signals lose their clean tone. Usually, reports are given as “5 & 9 aurora” on SSB, and “59A” instead of “599” in CW. It is referred to as Au in writing. As it is the aurora that the signals are ‘bouncing’ off, antennas have to be pointed east of north in the UK, and European stations also point roughly north. Periods of radio aurora rarely coincide with visual auroras, but both are more common during periods of high sun activity. You will also hear auroral effects on the lower bands but it is not the aurora that is making the propagation possible. 
  - If a signal is arriving via the north pole, it will often show signs of ‘**Arctic flutter**’, rapid fading that gives the signal a distinct tone. This is often the case with signals heard in the UK from KL7 (Alaska) and VE7 (British Columbia) on the low bands.
  - The **ARRL** (**American Radio Relay League** – sometimes referred to by American hams as ‘the League’) was founded in 1914 to represent American radio amateurs, although they also have a presence in Canada. Their headquarters are in Newington, Connecticut, and the HQ station callsign there is W1AW (see there). The ARRL monthly magazine is called QST (see there).
  - **AOS** = **Acquisiton of Signal**. This is when you can first hear a satellite which is just coming up over your horizon and approaching your station.

====== B ======

  - **Beacons** are stations that transmit all the time so that people can judge propagation. They will often append a “/B” to their callsign. Every amateur band has a section reserved for such stations and you should never transmit in these sub-bands as you would be interfering with the beacon signals. For information on the International Beacon Project see there.
  - The “**BFO**” (**Beat Frequency Oscillator**) was what used to be needed when listening to SSB and CW signals on old receivers. It is outdated now but you may come across it in old radio books and magazines, or on older and antique radios.
  - The **Bureau** (abbreviated to ‘**buro**’ in CW) refers to the QSL bureau system run by nearly all national societies. Members send all their outgoing QSL cards in one parcel to the bureau, which then similarly sends all the cards for one country in one package. Incoming cards are distributed by the Bureau to individual managers all over the country, who then send them to individual amateurs who have deposited envelopes with them. This system is obviously much cheaper for the amateurs who use it, as they do not have to send cards individually to each other, saving envelopes and postage costs. The RSGB QSL Bureau is free to members but can be accessed by non-members for a fee.
  - ‘**Beam**’ refers to any antenna which has more than one element, and offers gain over a dipole. The earliest beam was the Yagi (developed by the Japanese engineers Shintaro Uda and Hidetsugu Yagi – although the latter was the one who applied for the patent and got the name recognition) consisting of a driven element in the middle, with a director (shorter) in front, and a reflector (longer) behind the driven element. More (or fewer) reflectors and directors can be added, and there are many different ways of configuring beam antennas (see Spiderbeam, Hexbeam, Moxon beam).
  - ‘**Backscatter**’ occurs occasionally to HF signals, allowing communication between two stations who would otherwise be in each other’s dead zone. It has one similarity with Sporadic E (usually written Es) in that both stations would be pointing directional antennas away from the direction of the other station. 

====== C ======

  - Every radio amateur has a unique **callsign** which usually consists of a prefix, a number, and a suffix, although the prefix may be a number followed by a letter then another number as in 7X7 (Algeria) or 4X4 (Israel). There are exceptions to this rule (a recent one in 2014 was 7QAA) but they are relatively uncommon. The callsign should never be referred to as the ‘handle’, which is CB slang.
  - The “**Carrier**” refers to the unmodulated part of an AM or FM transmission (what you hear when there is no voice), or is the signal itself that is used to send Morse code. In Single Sideband, this carrier is suppressed so that the transmitted power all goes into the modulated (voice) part of the signal.
  - “**Chirp**” is the result of an unstable RF oscillator in a CW transmission. It is called this as it sounds similar to the chirping of birds, and is not something you would normally want. If you give a report to an operator whose signal is chirping, you may add the letter C after the RST report (as in “599C”). It used to be a characteristic of many signals from Eastern Europe in the days of the Iron Curtain, as many operators built their own transmitters from whatever they could scrape together, and did not have the necessary equipment to make sure the chirp did not happen.
  - “**CHIRP**” is a free, open-source software used to program many handheld radios. It supports a large number of manufacturers and models, as well as provides a way to interface with multiple data sources and formats. [[https://chirp.danplanet.com/projects/chirp/wiki/Home|CHIRP Software]]
  - **Contests** are highly competitive events organised by a variety of groups and organisations in amateur radio. They are normally held at weekends and are not allowed by a gentleman’s agreement to use the so-called WARC bands (see there). The object is usually to work as many stations as possible, often within a 48-hour period (eg from 00.00 on Saturday until 23.59 on Sunday), but the rules vary and can involve European stations working non-Europeans, Commonwealth stations working other Commonwealth stations etc. Competitors usually are required to give a report plus a serial number which increases with every contact (59 001, 59 002 etc.), or a report plus their age, membership number, power output etc. depending on the rules. Many people object to contests taking over the bands at weekends, and some popular ones involve SSB stations taking over the CW portions of bands or vice versa, which can mean that normal QSOs are all but impossible during the contest period. However, this has been the case for decades, and there is not much prospect of the situation improving any time soon. 
  - **CQ** is used for a general call, and means you are open to being contacted by anyone who can hear you. You may be more specific if you want to contact one country or continent only (eg “CQ DL” or “CQ Asia”), and you may just want to contact anyone outside your own continent (as in “CQ DX”). If you hear a European station calling CQ DX, you should not reply to them from the UK. Israeli amateurs (4X4 or 4Z4 callsigns) also do not want calls from Europe if they call “CQ DX” but are looking for stations further afield than that. In CW, it is common to call “CQ NA” specifically for North America, and “CQ SA” for South America. Stations taking part in contests will call “CQ contest” in SSB and “CQ test” in CW. Do not return their call unless you can give them the correct contest report, which varies according to the contest (see there).
    - **CQ Magazine** is published in the USA and is dedicated to people who like to operate their stations. In other words, it is less concerned with the technical aspects of the hobby, and more with operating your station for DX hunting, contests etc. They themselves run a few important contests during the year: The CQ Worldwide SSB and CW contests, held on the last full weekend in October and November respectively, and the CQ Worldwide WPX (see there) SSB and CW Contests, held on the last full weekend in March and May respectively.
  - “CW” is how most amateurs refer to Morse code. It stands for “Continuous Wave” as it is this wave that is interrupted to form the Morse signals.
  - Cluster is the expression for a website where people upload information on DX stations they have just heard, together with the frequency and any other relevant information. This is called ‘spotting’ on the cluster and sometimes a DX station will ask if you can ‘spot’ them. One of the first clusters was DX Summit, run by a group in Finland (new.dxsummit.fi), and they are still a reliable source of good up-to-date information on the bands.
  - **ClubLog** is an online logbook along the lines of Logbook of the World (see there). Set up by Michael Wells, G7VJR, this site is a goldmine of information on your own log (countries worked, confirmed, needed etc.) and worldwide statistics based on the thousands of logs that have been uploaded to it. You can upload your log to ClubLog and then provide a link to your log on the web so that people can confirm whether they are in your log or not. Many DXpeditions (see there) upload their logs daily to ClubLog to provide this service to the many people who call and work them. ClubLog also runs the OQRS QSL service (see there).
  - **CEPT** is the European Conference of Postal and Telecommunications Administrations (the acronym is based on the French name for the organisation). They are responsible for coordinating the rules of telecommunications administrations in European countries (including the Russian Federation). Most importantly for radio amateurs, there is a ruling (T/R 61-0  - that any amateur licensed in one of their countries may operate temporarily in any of the other countries without applying for a reciprocal licence. For UK licensees this is valid only for Full licence holders (Annex 2, T/R 61-01). In addition, Australia, New Zealand, South Africa, Israel and the USA have agreed to abide by the terms of the CEPT licence for holders of higher classes of licence. In all other non-CEPT countries you have to apply for a reciprocal licence (see there) to be able to operate legally, even temporarily.

====== D ======

  - Many amateurs refer to Germany as “**DL**”, as this was the most common prefix used in German callsigns for many years. Germany has been allocated the callsign block from DA to DR (DM being reserved for amateurs from the former German Democratic Republic, or East Germany, if they apply for it). The German amateur radio club is called the DARC (Deutscher Amateur Radio Club) with headquarters in Baunatal, and they publish a monthly magazine called CQ DL.
  - **DX** started off by being the morse abbreviation for ‘distance’, then became ‘long distance’, then came to mean any station outside your own continent, and/or operating from a rare location.
  - A **DXpedition** usually consists of a group of two or more amateurs who travel to a rare country (or nowadays ‘entity’) to activate it for amateurs who need it for DXCC or IOTA award purposes. The country may be an obscure island (such as Lord Howe, Kerguelen etc.), or one where there are few or no licensed amateurs at the moment (such as Iran, Ethiopia etc.). 
  - **D-Star** is a proprietary digital radio system, introduced by the Japanese manufacturer ICOM, and can therefore primarily only be accessed using ICOM equipment. It involves a network of repeaters, all (inter-) connected via the internet, whereby the user is automatically signed in to the system in a similar way to what happens when switching on a mobile phone. Many people object to the system tying them to ICOM equipment, and refuse to become involved with it for that reason.
  - **DXCC** is the DX Century Club, an award issued by the ARRL for amateurs who have proof of establishing two-way communication with 100 or more ‘entities’. This proof can be either QSL cards (see there) or confirmed contact on LotW. Entities used to be known as ‘countries’ but not all of them are countries as such (some are islands, or enclaves within countries). It is probably the most prestigious award that an amateur can earn, and there are endorsement stickers to be added to the original award (a paper certificate) for every 50 entities worked between 100 and 250, with additional rules above that number. In all, there are currently 340 entities on the DXCC list.
  - The **D layer** is one of the ionospheric layers which affect radio waves and stretches roughly from 60 to 90km above the earth. It is responsible for absorbing most radio waves at 10 MHz and below during the day, but loses its ionisation rapidly after sunset.
  - The **DXCC** Most Wanted List is compiled by asking active Dxers to list the entities they need in numerical order. The number one most wanted entity at the moment is P5 (North Korea) and the least wanted (or rather, needed) is Italy!
  - A ‘**dupe**’ is someone whom a DX station has worked before on that band and mode (eg 20 metres CW), or someone you have worked before in the same contest. The idea is to avoid being a ‘dupe’ to anybody by checking before you call them. In CW, the DX station will simply reply “QSO B4” (“I have worked you before on this band and in this mode”), so avoid wasting time and simply reply ”SRI 73” (sorry, and best wishes). This sometimes happens in a sporadic E opening on 6 metres, where QSOs are short and fast, and it is difficult to remember whom you have worked only half an hour ago. No-one thinks badly of you if you do it; we have all done this at some time even if computer logging helps to identify dupes.
  - **DQRM** (deliberate QRM – interference – of another station) is an unfortunate by-product of people having too much time and money in modern society. The phenomenon has always been with us, but seems to have taken on a life of its own in recent years, with a small group of people intent on destroying communciations between DXpeditions and the rest of the world. Various strategies have been developed by DX stations to counteract DQRM, such as frequently changing their transmit frequency by a few kHz, but the best advice to everyone else is to ignore DQRM, even if it can be extremely frustrating and annoying at times.
  - **dB** is a **decibel**, a relative value for measuring sound or power. Named after the inventor of the telephone, Alexander Graham Bell, the decibel is one tenth of a Bel, a logarithmic measure whereby 3 dB roughly equates to a doubling of a sound. S-meters on transceivers are calibrated up to S9 (loud), then in dB above that. So, when someone gives you a report of being “5 & 9 plus 10dB”, you really are loud. If the needle on the S meter goes completely over to the right, then you can be told you are “pinning the needle”, or “coming in like a local”.
  - **DF** is **Direction Finding**, a system of triangulating the position of a transmitting station, usually by three or more widely separated receiving stations at HF, and possible from one location at VHF. 

====== E ======

  - The **E layer** is one of the ionospheric layers that amateurs can refract signals from, and appears in the form of irregular ‘clouds’ at a height of 90 to 160 km. Propagation is referred to as ‘sporadic E’ and is written Es or Es.  Although there are many theories concerning sporadic E, no-one really knows what causes it. In the northern hemisphere it appears around December/January, and in late spring/early summer, lasting until August. It usually occurs on the 10 and 6-metre bands, but exceptionally also appears on 2 metres (144-146 MHz). Signals in Es can suddenly appear on an empty band, and be extremely loud for a few minutes before disappearing completely again. The sporadic E event itself can last for a few minutes or a few hours, and allows people to communicate over distances between 800 – 2200 km, plus or minus, or even more if the signal then experiences a ‘hop’ involving the F layer of the ionosphere.
  - The amateur radio band 3.500 to 3.800 MHz is usually referred to as ‘**eighty**’ (as this is roughly the wavelength in metres of the signals at this frequency). As the United States band carries on up to 4 MHz, US amateurs often refer to this band as ‘seventy-five’.
  - **eQSL.com** is a website dedicated to confirming QSOs without needing to send a QSL card. People upload their logs and, if the information more or less matches, can exchange electronic QSL cards with one another.
  - **Echolink** is an internet based amateur radio system, whereby licensed amateurs can communicate either completely over the internet (using VOIP, see there) or by using some combination of radio signals and internet links to establish contact. Many VHF repeaters all over the world are linked to Echolink and QSOs are possible at all times of the day and night from any location. The Echolink app is free to download, then you can register for and use it, after you have proved you are a legally licensed operator.
  - The term "**Elmer**"--meaning someone who provides personal guidance and assistance to would-be hams--first appeared in QST in a March 1971 "How's DX" column by Rod Newkirk, W9BRD (now also VA3ZBB). [[https://www.arrl.org/elmer-award|Elmer Award]]

====== F ======

  - The **F layer** is the most important layer of the ionosphere for radio communications and stretches from 150 to 500 km above the earth. In reality, there can be a splitting of this layer into F1 and F2 but the latter is responsible for most long-distance communication between 10 and 30 MHz (occasionally also up to 50 MHz). It is especially prominent during periods of high sun activity (see also the ‘sunspot cycle’).
  - The amateur radio band 21.000 to 21.450 MHz is usually referred to as ‘**fifteen**’ (as this is roughly the wavelength of the signals at this frequency in meters).
  - The amateur radio band 7.000 to 7.200 MHz (in Region   - is usually referred to as ‘**forty**’ (as this is roughly the wavelength in meters of the signals at this frequency).
  - ‘**Full legal limit**’ is how many US amateurs refer to the maximum permitted power output of their stations (1.5 kW).
  - **Footprint** refers to the area underneath a satellite where it can be heard or reached by transmitter. Obviously, the higher the satellite’s orbit, the larger the footprint will be.
  - **FAI** = **Field Aligned Irregularity**. More commonly referred to as ‘backscatter’, this is a mode of propagation whereby signals ‘bounce’ off a layer which is not in the actual direction of the station’s location you are receiving. A station to the north of you, for example, may be much louder (or even hearable at all) when you point your beam to the East, and completely in the noise when you point North.

====== G ======

  - Most amateurs refer to stations in England as **‘G’ stations**, as that used to be the main callsign prefix for England. (Even 2E0XXX or M0XXX could be referred to as ‘G’ stations.)
  - The **Grey Line** (sometimes ‘**greyline**’, or ‘**grayline**’ in the United States) is an imaginary line that runs around the earth every day, representing roughly 30 minutes before and after sunrise and sunset. Stations who are located on this line (one at sunset, one at sunrise) will often enjoy enhanced propagation and signals will peak remarkably before dropping away completely. In the UK, it is often a good time to work New Zealand and Australia on the Low Bands.
  - **Green Stamps** refers to US dollars. Many DX stations or their managers require you to send two or three Green Stamps ($2-$  - with your QSL (and an SAE) to cover postage and cost of printing the cards.

====== H ======

  - The abbreviation **HF** stands for **High Frequency** and refers to the radio spectrum between 3 and 30 MHz. In amateur radio practice it is used to refer to the bands between 14 MHz and 28 MHz (20 to 10 metre bands), the other bands either being the ‘Low Bands’ (see there), VHF or UHF (see there).
  - **HRD** refers to the amateur radio software **Ham Radio Deluxe**, a software suite that covers many areas of computer radio control, computer logging, digital communications, maps etc.
  - In Morse, the abbreviation **HI** (di di di dit  di dit – or, more usually, di di di dit  dit dit), means ‘I’m laughing (the same as lol in texting). Some amateurs use it when they are actually talking on the radio (or using ‘phone’ as we say), which is meaningless but WTF, it’s up to them.
  - Once a year in Friedrichshafen in the south of Germany on Lake Constance (Bodensee in German) the biggest amateur radio exhibition in Europe is held on the three days of the last full weekend in June: the ‘**Ham Radio**’. Visitor numbers in 2014 were 17,100 with over 200 exhibitors.
  - In spite of the popularity of the ‘**Ham Radio**’ exhibition, many people find the expressions ‘**radio ham**’ and ‘**ham radio**’ to be a bit insulting, and prefer to be called ‘radio amateurs’ and talk about ‘amateur radio’. Nevertheless, we do talk with pride about Ham Spirit, the legendary willingness of radio amateurs to help fellow hobbyists with time, advice, loans of equipment, or other kind of support. The origin of the word ham to refer to radio amateurs is unclear, although many theories have been proposed over the years.
  - An **HB9CV** antenna is a two-element antenna usually for VHF frequencies, named after Rudolf Baumgartner, callsign HB9CV, who came up with the design in the 1950s.

====== I ======

  - A popular Japanese radio manufacturer, Icom makes transceivers which are in use all over the world. The company also introduced its own proprietary digital voice system called D-Star (see there).
  - The IARU (International Amateur Radio Union) was established in 1925 to represent national radio amateurs (then, later, their national societies) worldwide. The ITU (see there) recognises the IARU as the official representative of radio amateurs at conferences (such as the WARC, see there). 
  - The ITU is the International Telecommunication Union, an agency of the United Nations, based in Geneva. It is responsible for world-wide radio communication matters, and supervises the allocations of radio spectrum all over the world. The ITU allocates the international callsign blocks, and has given itself the callsign block 4U. The station 4U1ITU operates from Geneva and  4U1UN operates from the UN building in New York (both separate DXCC entities). 4U1VIC operates from the UN Vienna International Center but counts as Austria for DXCC purposes, and 4U1WB can be heard from the World Bank HQ in New York, but counts as USA for the DXCC.
  - IOTA stands for Islands on the Air and is an award programme, now run by the RSGB, similar to the DXCC for proving two-way communication with a number of islands or island groups worldwide. Over the years it has become very popular all over the world and the IOTA Contest on the last full weekend in July has become one of the main contests in the amateur radio year.
  - The International Beacon Project was set up and is run by the Northern California DX Association and the IARU. The programme involves beacon stations on every continent which transmit in a fixed order every three minutes on a tight schedule on the following frequencies: 14.100, 18.110, 21.150, 24.930 and 28.200 MHz. Each beacon transmits every three minutes, day and night. A transmission consists of the callsign of the beacon sent at 22 words per minute followed by four one-second dashes. The callsign and the first dash are sent at 100 watts. The remaining dashes are sent at 10 watts, 1 watt and 100 milliwatts. These frequencies should be kept clear of all normal traffic (even if you cannot hear anything at any given moment).
  - IRCs are International Reply Coupons, issued by Post Offices and used to pay for one stamp covering international airmail postage. Most people nowadays do not accept them (because of questions of validity in some countries), and their use has nearly disappeared completely in amateur radio.
  - The ISWL (International Short Wave League) was founded in England in 1946 and still has an active membership of licensed amateurs and SWLs. They run their own on-air nets and QSL bureau, issue awards, run contests, and have two dedicated league callsigns (G*4BJC and M*1SWL) that members can operate for a month at a time.
  - IF = Intermediate Frequency
Without going into too much detail, this is the frequency that a signal is shifted to by means of a local oscillator, so that amplification and filtering can all be carried out at one frequency rather than for every possible frequency to be received or transmitted.

====== J ======

People refer to Japanese stations as ‘JAs' as that is the most common prefix in Japan. (Japan was actually allocated the callsign blocks from JA to JS.)



====== K ======

  - Many US stations have a callsign prefix of either K or K plus another letter. For commercial radio stations in the USA, the K callsign is almost always used west of the Mississippi, but that restriction never applied to amateurs. KL (usually KL7) is reserved for Alaska, KG4 plus a two-letter suffix is usually Guantánamo Bay, KC4 with a three-letter suffix is Antarctica, KP4 is Puerto Rico, KP2 is US Virgin Islands etc.
  - In Morse, the letter K (da di dah) means ‘go ahead’ to the other station. You can sometimes hear people using it on phone. Unnecessary? Yes, but you’ll still hear it.
3  - Kenwood is another popular Japanese radio manufacturer. Their equipment used to be imported into the UK under the trade name Trio, and many of these rigs are still around on the second-hand market.

====== L ======

  - A logbook (often just ‘log’) contains all relevant information on when your station transmitted, who you were in contact with, in what mode, and on what frequency. Logbooks used to be on paper, but most people run them on computers nowadays. They were compulsory in the UK until just a few years ago, but nevertheless most amateurs still keep a logbook. Apart from anything else, they provide you with information on when you were active, useful information in case a neighbour complains about interference. In such cases, Ofcom may in fact insist that you keep a logbook until an interference case has been successfully dealt with.
  - LotW refers to the Logbook of the World, an online database run by the ARRL. The ambitious goal of LotW was for as many amateurs as possible to upload their logbooks, so that there would be an online confirmation of two-way contacts between amateurs. In order to be accepted and register for LotW access, you must provide proof of being licensed  with your call, and they will then send a secure access code to you which is stored in your computer and used when you upload logs to the system. LotW confirmation is considered valid proof of a contact for a DXCC application, and a paper QSL card is not necessary if both logs on LotW agree.
  - The Low Bands are the 1.8, 3.5, 7 and 10.1 MHz bands and now include the channelized allocation around 5 MHz, the so-called 60 metres allocation.
  - ‘Linear’ is short for ‘linear amplifier’ and refers to an RF amplifier which boosts the power of a transmitted signal (up to 400W in the UK, 750W in many European countries, and 1.5kW in the USA).
  - The ‘Locator’ system (sometimes referred to as the ‘Maidenhead’ locator as this was the English city where it was first agreed on) is a means of defining the rough geographical position of a station anywhere on the planet. It was developed by Dr John Morris, G4ANB, and replaced the old QRA locator system that was only valid within Europe. It consists of two letters, two numbers, then two letters (two further numbers may be added, but in practice never are). An example would be IO86NL, which covers an area around Dundee. It is only really useful for amateurs on VHF (six metres and above) but is sometimes mentioned by people in HF contacts.
  - LOS = Loss of Signal. This is when a satellite goes below your horizon and you can no longer hear it.

====== M ======

  - MFJ are an American company that manufacture a wide range of radio accessory equipment such as antenna tuners (ATUs), antenna analyzers, power supplies, loop antennas etc.
  - Stations who are operating when mobile (in a vehicle) give their callsign plus the word ‘mobile’ in voice or /M in CW or in digimodes. Although licensed radio amateurs in the UK are exempt from the law against using a mobile phone while driving, in practice it is not a good idea to test whether the local police are aware of this. Be discreet when operating and never take risks. People say ‘bicycle mobile’ which is not strictly speaking correct but is heard on the bands. If operating on a bicycle you should just say ‘portable’ or send /P in CW or digimodes. You may also hear someone saying they are ‘pedestrian mobile’.
  - Stations operating in international waters should append /MM to their callsign and say ‘maritime mobile’ after their callsign in voice.
  - MARS stands for Military Auxiliary Radio System and is a US backup communications system for the Army and Air Force. Most stations are licensed radio amateurs, and they operate on frequencies above or below amateur radio bands.
  - MS is Meteor Scatter, bouncing signals off ionised trails left by incoming meteors into the atmosphere. Most meteor scatter QSOs are as a result of skeds, but random contacts are possible. Because of the nature of this mode, 6m and 2m are the preferred bands.
  - The ‘Magic Band’ is six metres (50 to 52 MHz in the UK). This is because of the band’s position on the spectrum, between VHF and HF, which means it can be completely empty for long periods, then suddenly spring into life, with stations every few kHz to be heard for either a few minutes or hours, then go completely dead again. Propagation can be tropo, Es, MS, or auroral, which is similar to VHF, or at times of high sun activity, even F-layer propagation, allowing contact between Europe and the Far East, South America etc. just like the HF bands. It is its unpredictability that gives it the Magic in its name.
  - MUF is the Maximum Useable Frequency, the highest frequency at a given time that will reflect (refract) signals from the ionosphere. Above the MUF, signals penetrate the ionosphere and carry on into space.
  - ‘Manager’ see QSL Manager.

====== N ======

  - Many US callsigns begin with an N. This used to be only for General Licence holders in the USA, but can now be heard from Extra licence holders as they no longer need to change their callsign on upgrading. There used to be an American Novice licence but that was dropped in the year 2000 when the entire American licensing system was overhauled.
  - NoV is a Notice of Variation to an amateur radio licence issued by Ofcom in the UK. For example, at the moment Full licensees can apply for an NoV to operate digital modes from 146 – 147 MHz. People wishing to use a Special Event callsign must obtain an NoV from Ofcom first, as do contesters who apply for a special (shortened) contest call.

====== O ======

  - Ofcom (the Office of Communications) is the organisation tasked by the UK government with regulating everything concerning the use of the radio spectrum in the UK and Crown Dependencies. This means that they are responsible for issuing amateur radio callsigns and licences plus enforcing radio regulations. Although the RSGB has taken on the job in the UK of administering amateur radio exams, it is still Ofcom that issues the licence after a candidate has passed the exam.
  - OQRS is a system run by ClubLog of administering QSO confirmation online. You check whether your callsign is in a DX station’s log, then pay a fee (normally around $2/$  -, and a paper QSL will then be sent to you confirming contact(s). This saves postage and QSL card costs on your side, and automates the process of sending QSL cards from the DX station’s point of view.
  - OTH (or sometimes OTHR) refers to Over The Horizon Radar, a shortwave radar system that allows various countries to detct and follow incoming missiles and/or aircraft over enormous distances (up to several thousand kilometres). Sometimes these transmissions take place on amateur bands and can cause total disruption of reception over a wide range of frequencies for several minutes at a time. One of the worst offenders was the Soviet ‘Woodpecker’ (see there), located near Chernobyl in Ukraine, in the 1970s.
  - OM is the CW abbreviation for ‘Old Man’, an affectionate term used to address the station you are in contact with. Some countries use the abbreviation on Phone as well to refer to a fellow radio amateur. 

====== P ======

  - ‘Phone’ is still how many people refer to voice communications in amateur radio. It can include SSB, FM and AM, as well as digital voice nowadays.
  - Many American amateurs refer to QSL cards as ‘pasteboards’.
  - ‘Prefix’ is the part of the callsign before the number, such as EA1XXX, G5RV, W1AW, that defines the country the licence was issued in. These prefixes are taken from the ITU prefixes allocated to each country recognised by the United Nations (although there are exceptions such as 1S for the Spratly Islands, 1K for the Knights of Malta etc.).
  - People refer to unlicensed operators who use either fictitious callsigns, or borrow someone else’s, as a ‘pirate’. There used to be a pirate who gave the call PHØNEY every now and then (which, years ago would have been an unusual prefix for the Netherlands), and would entice hundreds of people to create pile-ups on 40 metres.
  - A ‘pile-up’ or ‘pile’ occurs when dozens (or hundreds) of people are calling one station at the same time. 
  - /P = Portable, and is appended to a callsign if the operator is not at a permanent address and only temporarily at this location. It is often used by IOTA and SOTA stations in the field, and has begun to take on the meaning of a station that will probably be interesting to work for this reason. 

====== Q ======

  - The ‘Q’ codes were originally developed to make communications by (radio) telegraph quicker and more efficient. They used to be used in the form of question and answer (‘QTH?’ = Where are you located?; answer ‘QTH Dundee’ = My location is Dundee) but nowadays we are less strict about how we use them. (Even if you can read otherwise in some publications – this is the reality.) The codes all start with Q and then have two more letters. Probably the most common in amateur radio today are: 
    * QSL = either used as a question to mean ‘Do you confirm?’ or to refer to a QSL card, which contains all the information on a QSO to confirm that it took place (including date, time, frequency, mode, signal report). A ‘QSL manager’ is someone who has offered to take over the administration of QSLing for another station. This station sends his QSL manager his logs, so the manager can check that a QSO has taken place and return a QSL card confirming this to people who have asked for one. It is customary to include a self*addressed envelope with a direct QSL card, plus $2 or nowadays more often $3 (often called ‘green stamps’) for postage and printing costs. 
    * QSO = two*way radio contact between two stations; a radio conversation (sometimes now abbreviated to Q).
    * QTH =   your station’s location. “My QTH is Dundee.”
    * QRL? is used in CW to ask whether a frequency is in use before calling CQ or making contact with anyone else. (It used to mean “Are you busy?”). German amateurs use QRL to refer to their place of work.
    * QRG = frequency
    * QRM = interference (from other signals on or near the same frequency)
    * QRN = atmospheric interference
    * QRS = send (CW) more slowly; slow down your morse
    * QRQ = send (CW) more quickly; speed up your morse
    * QRO = high power (more than 100 watts output)
    * QRP = low power (usually means an output of 5 watts or less, but some people use it to mean 10 watts or less)
    * QRZ = Who is calling me? Used if you know someone is calling you but you have either not heard him clearly enough to catch the whole call, or just could not distinguish one call when several stations call at the same time. DX stations use QRZ? to mean they have finished a QSO with one station and would like people who are waiting to call now.
    * QSB = fading
    * QST = is used in America to mean a general call with news from the ARRL HQ station W1AW, and is also the ARRL magazine published monthly for members.
    * QSX = used in CW to tell operators that a station is listening on a different frequency from his transmit frequency. So, “QSX up 1” means a station is listening 1 kHz higher than his transmitting frequency.
  - A QSL card is postcard sized, nowadays often with a photograph on the front, and contains all the information on a two*way contact made between two stations (QSO), confirming this contact. They can be sent direct, via a QSL bureau, or using the OQRS system.
  - A QSL manager offers to take care of receiving and answering all incoming QSL cards for a DX station. Some managers (eg W3HNK) handle hundreds of such stations.
  - QRZ.com is probably the most used amateur radio site on the web, and is free unless you wish to become a subscriber, which gives you additional user privileges. Nearly all licensed amateurs are registered with the site, and have their own page, which may only contain basic information such as name and address, or can be quite elaborate with photographs and long texts (sometimes rants☺), online logbook etc. The home page of the site has links to amateur radio related news stories, some adverts, and links to discussion forums on a wide range of amateur radio subjects.

====== R ======

  - The RS(T) report system is used in amateur radio to tell the station you are in contact with how well you are receiving them. RS stands for Readability and Strength and is on a scale from 1-5 for readability, and 1-9 for signal strength. A perfectly readable, loud signal is “5 & 9”.  Giving reports is meant to be based on what the S-meter on your transceiver is showing, but in practice it’s far from an exact science, and many stations give everyone 5 & 9, even if they are not hearing them too well. The T part of the report refers to the Tone of a CW signal and is invariably given as 9. So a perfectly readable, loud CW signal with a clear tone is “599”. This is often abbreviated to “5NN” as it is much faster to send. Old (and some young) fogeys complain about people giving wrong reports, but it has happened now for decades, and is not going to change in the future. If somebody says your signal is 5 & 9 but “please repeat your name and QTH”, obviously the report is wrong, but they may say “You are a real 5 & 9”, which is probably true! Based on an older reporting system, people still sometimes say a signal is “Q5”, meaning perfectly readable.
  - The Radio Society of Great Britain (RSGB) is the biggest organisation in the UK representing radio amateurs with Ofcom and the IARU. The society had 22,600 members as of the AGM in April, 2015. It publishes a monthly magazine, Radcom (formerly Radio Communications), and two offshoots: Radcom Plus (for more technical articles – only available online), and Radcom Basics, which is sent out to subscribers by email every two months.
  - RTTY (pronounced ‘ritty’) is Radio Telegraphy Typing, and used to be produced by big, glorified typewriting machines, similar to the telex machines in the latter half of the 20th century. They were loud and slow, but were loved by many amateurs for their noise and smell. Nowadays, this mode is usually sent and received by computer programs using sounds generated by the computer sound card and then transmitted by the transceiver.
  - RIT is Receiver Incremental Tuning and allows most modern rigs to vary the receive frequency up and down by a few Hertz or up to a couple of kiloHertz. You may have to use this if someone comes back to your CQ call and does not zero-beat with your signal. For some reason, Transmitter Incremental Tuning is abbreviated XIT 😉.
  - RF = Radio Frequency
Often used simply as a synonym for radio signal(s).

====== S ======

  - SSTV stands for Slow Scan Television, and is a popular way of sending pictures via amateur radio. Although the digital TV mode is taking over some of the traffic, you can still hear the unmistakable warbling sound of SSTV on the bands. In Europe, the SSTV calling frequencies are: 3.730, 7.165, 14.230, 21.340, and 28.680 MHz and SSTV signals can be heard just above and below these frequencies.
  - ’SES’ are Special Event Stations, that usually have a special callsign issued for that event only. Recent examples are GB100RSGB for the 100th Anniversary of the founding of the RSGB, YL90IARU for the 90th anniversary of the founding of the IARU etc. There are permanently licensed SES, such as GB2SM in the Science Museum in London, DL0DM in the Deutsches Museum in Munich, W6RO on the Queen Mary, Long Beach, California etc. US SES callsigns have recently started to consist of only one-letter prefix, number, then one-letter suffix, such as K3B etc., and this format has also recently been applied to Dxpeditions to rare US-administered territories such as K1N (Navassa Island) etc.
  - The ‘suffix’ is the one-, two-, three- or more-letter part of the callsign after the number that is issued to the individual or organisation the callsign belongs to. Over the last few years, it has been more and more customary for SES callsigns to have long suffixes (such as  ER90IARU, UP60SPACE, IR2EXPO, etc.). 
  - A ‘Slim’ is an expression usually only used by US amateurs to refer to someone who is claiming to be operating from a rare DX location but is either nowhere near it, or operating from a ship anchored near the country. No-one knows the origin of this expression.
  - A ‘sked’ is a scheduled meeting arranged between two amateurs on a particular frequency, on a particular day, at a particular time. Some people have kept skeds for decades, some meet every day, some only make one sked and never have a contact again.
  - ‘Split’ is the term used to describe when a station is listening on another frequency than he is transmitting on (see also QSX). If you ever accidentally transmit on a DX station’s frequency you will immediately hear several people shouting ‘SPLIT’ (usually pronounced SPLEETA!) at you☺.
  - SINPO is a system for reporting reception of signals, used by SWLs sending reports to broadcast stations. It stands for Signal, Interference, Noise, Propagation, Overall. It was used initially on 60 metres when it was opened up to people who had the appropriate NoV, but has been replaced by the normal RST system now the band is open to all Full licencees.
  - SWL is a Short Wave Listener, some of whom are also licensed radio amateurs.
  - The Sunspot Cycle is a feature of the sunspots appearing on the sun’s surface and takes roughly 11 years to go from minimum to maximum, then another 11 years with the other polarisation to do the same. The peak of the 11-year cycle produces many sunspots on the sun’s surface and is a period of excellent HF propagation, whereas the trough of the cycle can mean a few years of very poor HF propagation. At the moment (autumn 2020), we are in the trough of Cycle 24 with Cycle 25 just appearing, which has been a disappointing (even though double) peak compared to many previous cycles. 
  - SR means Sunrise, and is often used in the context of the greyline (grayline in the USA).
  - SS refers to local Sunset.

====== T ======

  - Transmitter Incremental tuning (see also RIT) is abbreviated XIT for some strange reason😉.
  - ‘Tropo’ is short for tropospheric propagation, or tropospheric scattering, when a signal is refracted back to the earth at VHF/UHF after passing through turbulence in the atmosphere. The troposphere extends from the earth’s surface to about 12 km above the surface.
  - ‘Top Band’ is the 1.810 to 2 MHz band. 
  - TCA = Time of Closest Approach, the time when a satellite is neither approaching your station nor is it yet receeding. In practical terms, this means that your receiver does not have to take into account the Doppler Effect and you can listen to it on its set frequency.

====== U ======

  - UHF is Ultra-High frequency, from 300 Mhz to 3 GHz.
  - When a DX CW operator sends UP, he means he is listening (usually 1 kHz) higher than his transmit frequency. If someone accidentally transmits on the DX station’s frequency, you will hear a number of attentive people (sometimes referred to as “band policemen”) sending UP UP UP until the offender realises what he has done. The fact that they themselves are often in effect QRMing the Dx signal does not seem to enter their heads.

====== V ======

VHF is Very High Frequency, from 30 to 300 MHz.


====== W ======

  - WWFF is the organisation Worldwide Flora and Fauna in amateur radio, dedicated to promoting nature by means of radio. Activators operate /P from national parks and nature reserves which have been assigned reference numbers, and people try to work as many of these individual sites as possible. The reference number consist of the prefix for the country + FF + a number: eg LAFF-031 (Norway), GMFF-117 (Scotland) etc. The following frequencies are favoured by WWFF operators: Phone 3.744, 7.144, 14.244, 18.144, 21.244, 24.944, 28.444; CW 3.544, 7.024, 10.124, 14.044, 18.084, 21.044, 28.044 although they are obviously not always available and should always be read ± QRM. In addition to sending 73, operators often add 44 in Phone and CW.
  - WARC was the World Administrative Radio Conference, now known as the World Radio-communication Conference, organised by the ITU. At the 1979 WARC, three new amateur radio bands were introduced: 10.100 to 10.150 MHz, 18.068 to 18.168 MHz, and 24.890 to 24.990 MHz, and most administrations opened them up for amateur radio use in 1980. We still refer to these as the ‘WARC’ [pronounced as a word and not spelled out] bands, and they are the only bands that are by gentlemen’s agreement free of contest operating.
  - ‘W’ or ‘Ws’ are stations from the United States. This was because the first licensed USA stations after WWII had callsigns beginning with a W. You will hear phrases such as “The Ws are starting to come in again around lunchtime,” meaning propagation is opening up over the ‘pond’ to America from Europe.

====== X ======

XYL used to be an abbreviation used in CW (and then in Phone too) to mean your wife (ex-Young Lady) but many women find it demeaning nowadays. Use it with care☺!



====== Y ======

  - YL operators are ‘Young Ladies’ from the CW abbreviation. Female radio amateurs are frequently referred to as YLs, and some have actually asked for callsigns ending in YL. Although many female operators nowadays cringe at this expression, it has been around since the very beginning of amateur radio and will prove difficult to eradicate.
  - YOTA means Youngsters On The Air and is an organisation of people below the age of 25 in Region 1 (Europe, Africa, Middle East and Northern Asia) who are interested in amateur radio. They get together for a week every summer in a different country (2015 was Italy’s turn). 

====== Z ======

Although Americans pronounce this letter ‘**zee**’, most older American operators still call it ‘**zed**’ as it can otherwise be confused with ‘C’. In heavy QRM, the phonetic ‘**Zulu**’ can often be confused with ‘Juliette’ (same vowel sound) so people will say ‘**Zanzibar**’ or ‘**Zeppelin**’ to make it clear.

====== 44 ======

**44** used by operators in the Flora and Fauna programme instead of 73, originating in **Four Four** (**Flora Fauna**) and echoing the frequencies they use which end in 44, such as 14.244 MHz etc.


====== 72  ======

**72** often used by QRP operators instead of 73; not that the best wishes are any less, but just to show that – as with power output – less can mean more.



====== 73 ======

**73** is the abbreviation carried over from the old land telegraph days meaning ‘Best Wishes’. There are many ways of saying this (‘seven three’, ‘seventy three’, ‘seventy threes’ etc.) and arguments can be heard for and against any one of them. In reality, it originated in Morse code, and was a sound (actually a prosign) rather than an actual number, so how you pronounce it is up to you. People can even be heard saying ‘Best 73s’ which is claimed by the purists to be redundant as it means ‘best best wishes’; however, we also say things such as ‘Thanks very much’, ‘Thanks very much indeed’ etc. which also mean no more than ‘Thank you’ and everyone understands it is being used to strengthen the sentiment being expressed.

====== 88 ======
  
**88** originally meant ‘love and kisses’ and is often used as a final word to YL operators at the end of a QSO. It is not to be taken literally, and many YLs would not find it condescending or sexist if you used it, even if it is used less frequently nowadays. Again, it can be pronounced ‘eighty eights’.


====== 100% ======

An expression used by many non-native speakers of English in QSOs, as in “My QSL card **100%** to you.” This probably originated in people saying “I QSL 100%”, which meant that they send a QSL card for every new station they work, 100% of them, and this then became corrupted by people who did not understand 100% of what was being said to them.