Islands on the Air (IOTA) Contest
Help for newcomers
Getting started with the RSGB IOTA Contest
Here's a summary of how inexperienced contesters can enter the IOTA contest. Welcome!
Basics
First of all – be reassured. Contesting is meant to be fun, and you can enter without any previous experience. If you have tried one of the shorter RSGB contests, such as the 80m club contests or the VHF/UHF UKAC contests, you have a head start. The main difference you will notice is that the RSGB IOTA Contest is likely to be faster and more international. It should also be more exciting – isn’t that what you're here for?
This web page will tell you more about the contest, how to get on the air, what to expect, and how to send in your entry. You may already know most of what you read here, but you might also pick up a hint or two along the way. The emphasis is on entrants using SSB, although CW methodology is not very different. Listen to good contesters, on any mode, to learn the best techniques. The advice here is aimed mainly at first-time UK entrants, but of course, the principles are the same wherever you operate from.
You need a rig that covers the HF bands, and at least one suitable antenna. The contest takes place on five bands – 3.5MHz, 7MHz, 14MHz, 21MHz and 28MHz. Both SSB and CW can be used – you can work stations on both modes (which count separately), so there are ten possibilities for contacting each station. You need to decide which bands to operate on, which may be determined by the antennas you already have or want to put up.
The rules are on http://www.rsgbcc.org/hf/rules/2012/riota.shtml . If you have limited contest experience, you just need to know enough to get started. The date is always the last full weekend in July (in 2012, 28-29 July), from 1200–1200 UTC, that's 1 p.m. Saturday to 1 p.m. Sunday UK time. Everyone sends a signal report, but don't be surprised if you virtually always receive 59 or 599. To save time, HF contesters are in the habit of doing this regardless of the actual signal strength! You also send a serial number, starting at 001, and continuing on regardless of band changes. So, for example, if you change band when you have reached serial number 123, you continue on the next band with 124, and so on.
As you look at the rules, you will see that there are a number of options as far as your entry is concerned. The contest allows both CW and SSB contacts, and entrants can choose whether to use one or the other, or both. There is a category for those who want to operate for 12 hours or for 24 hours – as a newcomer you will probably want to maximise your effort by using the full 24 hours. And you can choose whether to enter with QRP (5 watts), low power (100 watts), or high power (over 100w). This choice will may well be determined by your class of licence, but good advice for those starting on the IOTA contest is to use the highest power that you are permitted, so as to increase your chances of making the QSOs and multipliers needed. When you submit your entry, the "robot" will confirm these choices with you.
The essence of the contest is to work as many island stations as possible. Although you can work any station, island or non-island, contacts with islands score more points, and only new islands count as multipliers. How do you know if a station is on an island? Because after sending the serial number, island stations also send an island reference, but non-island stations don't send any reference. The reference consists of a continent abbreviation, for example EU for Europe, and a number, allocated by the RSGB IOTA Committee. Stations on the UK mainland are in IOTA reference EU005. Other references can be found on:
http://www.rsgbiota.org/info/search.php . So, for example, search for "Wight" and you will see that the IOTA reference for the Isle of Wight is EU120.
By the way, you may be asking "What is a multiplier?" When you (or your computer) have added up the score from QSO points, you multiply that by the number of multipliers you have contacted. The IOTA contest rules will give you more details of how this is done. But it's easy to see that it is very important to find and work as many island station multipliers as possible, because your score will receive a big boost. Have a look at the results from previous IOTA contests to see the difference between just making QSOs, and making QSOs which are also multipliers.
On the air
If you are new to international contests, the easiest way to start is with “Search and Pounce”, or S&P. Tune the band in a systematic way, looking for stations you haven’t worked – if you are using logging software, this will tell you immediately if a station is a "dupe". You will not be popular if you often call stations when they know from their log that you have already worked on this band and mode! You will be looking particularly for island stations -- some will be in great demand: if so, note the frequency and move on, coming back later when things are quieter. Otherwise, when they ask for new callers, call just once, using the phonetic alphabet. Be ready to copy down the information sent, and be ready to send you own.
If you miss anything, ask for a repeat before you send any of your own information. When you have everything copied, send your own report and island reference, without unnecessary verbiage. People usually don't have time for chatting, although you might add a “Good luck Bob”, or other sociable greetings if you know who is operating. But your friend won’t be pleased if you spend so much time on pleasantries that your contest information is lost in QRM! After a dozen or so QSOs, you will get the idea of S&P.
Here's an example. You are G9XYZ.
CR3T: CQ contest, Charlie Romeo three Tango, contest
YOU: Golf nine X-ray Yankee Zulu
CR3T: G9XYZ, 59, 327, Alpha Foxtrot one four
[he sends you serial number 327, and his IOTA reference is Africa 014. Note or remember this information, and transmit as soon as he finishes]
YOU: Roger, 59, zero nine seven, Echo Uniform five
[you send serial number 097, and IOTA reference EU005]
CR3T: Thank you, Charlie Romeo three Tango, contest
So far, so good. Now conditions are poor, and there are requests for repeated information.
K1TTT: .... Kilo one Tango Tango Tango contest
YOU: Golf nine X-ray Yankee Zulu
K1TTT: The golf nine station, again
YOU: G9XYZ, Golf nine X-ray Yankee Zulu, over
K1TTT: G9XYZ, thanks, 59, 1x22
[he sends his serial number, but you miss the second digit. Ask for a repeat before sending your information. He's not on an island, so sends no island reference]
YOU: Number again, please
K1TTT: 1322, 1322, over
[got it this time]
YOU: Roger, 59, two four one, Echo Uniform five
K1TTT: Is that two four one? Over
[if he's got it right, just agree]
YOU: Roger, roger, roger
K1TTT: Good luck, K1TTT, contest
When it is harder to copy information, you might be more repetitious. Follow the example of the station you are working, who may be more experienced.
You might decide you want to call CQ Contest yourself. You can get an idea of how good operators do this by listening to them making these sorts of QSO for a few minutes. Before starting, as at any other time, always check that the frequency isn’t already in use. The rules specify some more limited segments than the whole band, for instance, on 20m -- check first. Callers will expect you to reply instantly to their calls, and to copy the information without asking for excessive repeats. Don't be frightened to call CQ, but be aware that even a lowly "G" station can generate a pile-up, with five or six calling people at once – this is mainly because island stations such as those in the British Isles score higher than non-island. Work out in advance how you will deal with this, and listen to what other good operators do.
But also remember that it's often normal to make up to ten CQ calls before getting a reply, sometimes more, even for the best-equipped stations. On a quiet band, you could wait for minutes at a time before getting any callers, although you would also ask yourself if you are really on the right band at all in this case! Many operators now get their computers to perform the job of calling CQ, using MP3 voice files or similar, and CW operators almost always use the computer to send CQs, as well as other contest information.
There is a good general description of HF contesting by G4BUO:
http://www.rsgbcc.org/hf/information/guide.shtml
This will give you ideas about the RSGB IOTA and other contests.
Which Band?
If you are equipped for several bands, you will need to choose the band to operate on. As a rule, you would use the highest frequency that is open at the time, although this is a very general statement. If you can hear signals on 10m, that is a good place to start, and then look on 15m. However, unless sunspot activity has recently been high, 20m is likely to be the mainstay of contest operation, with 15m also good if conditions are reasonable.
From the UK at present, 20m is likely to be open to Eastern Europe (and further afield) in the mornings. Propagation gradually opens up to the North America from around midday, and tends to die down in the evening. You will probably find Western Europe available most of the day and evening. If you can only equip yourself for one band, 20m should probably be it.
As far as the IOTA Contest is concerned, you might therefore find a mixture of European and US stations on 20m soon after the contest begins. If you stay on the band, you could expect North America to predominate into the evening, always mixed with Europeans. Later on, many stations will move lower in frequency, but it is always worth checking the band just in case. The next morning on 20m will see stations from the East predominating, but you are likely to find Western Europeans on at any time.
If you have an antenna for 40m, you should have no trouble working European stations, including plenty of multipliers, throughout the evening and overnight. If you have 80m, you will find it is also most used once it gets dark, although some stations will frequently be found as early as 1600 or 1700 UTC. There can be high levels of static on 80m, which makes it a harder band to use during the summer.
Your Dipole Antenna
We've already noted that 20m is the band to go for if you can only choose one band. This is where you would be able to make several hundred QSOs and perhaps 30-40 multipliers without using any other band. If you already have an HF antenna available (for 80m, perhaps, or a G5RV), you can try it on 20m, and see if it works. Most radios have an automatic ATU, which may well be able to tune up your existing antenna. But as a test, be certain that you can readily make international contacts with reasonable reports before considering that you have an effective antenna.
Even if this works, it is far better to put up a 20m antenna -- specifically for the contest if you cannot make it permanent. The easiest antenna is a dipole, fed with 50 ohm coaxial cable, supported at the ends (and in the middle if possible, although this is not often feasible).
Perhaps your aerial will look like this. The length L in the diagram will be around 16.5 feet for a 20m dipole. So the total length would be 33 feet, plus a little extra for the rope attaching to the end supports. There's a good reason why the half-wave dipole such as this is so widely used -- it’s the single most useful antenna in a radio amateur’s repertoire. It’s simple, effective, and flexible. A half-wave dipole can be put up in minutes, and is likely to work first time with minimal adjustment. You can calculate the total length from the formula, in traditional units, 467/f, where f is the frequency in Megahertz, and the result is in feet.
Any reasonable supports can be used for the aerial – the end of your house and a tree, for example. For a 20m dipole you will get best results if all of your antenna is over 20 feet high, and 30 feet is even better. If the supports are of different heights, it’s not too important. Where the space available is not quite long enough, then stretch out the dipole symmetrically, and bend the ends down towards the ground.
The two halves are connected to the centre and braid of the coaxial feeder, and an indefinite length of coax can be used to connect to the transceiver. You may find that a balun is not essential – if you buy one, you need a 1:1 ratio. The off-the-shelf types of balun will probably also have connectors which will give you a place to tie off the wires and make them easier to connect.
Another type of balun can be made by forming about half a dozen turns of the coaxial cable into a coil, at the point where the cable joins the aerial itself, around 8-10 inches in diameter. Tape up this coil, and leave it in place, dangling beneath the dipole. Of course, if your antenna is not supported in the centre, the weight of this coil may reduce the overall height, which is less desirable.
Normally you would make the dipole slightly longer than the formula, and then cut sections off (the same amount each side) until the correct length is achieved. How do you know the correct length? You measure the Standing Wave Ratio (SWR), either from the rig itself, or from a separate meter. An SWR of 1:1 means the impedance is 50 ohms. Transceivers can usually tolerate an SWR of up to 2:1, so as soon as you get between 1.5:1 and 2:1 you would be satisfied.
You may say that you can get on the band well enough by tuning up a piece of wire from your shack window. One of the main advantages of the dipole over such a random piece of wire is that it separates the antenna itself from the feed line. The coax should not be involved in radiating a signal; on the contrary, radiation takes place only from the antenna itself. As long as the dipole is as high as possible, you have maximised the effective overall height, and reduced the possibility of causing and receiving local interference.
The Inverted Vee variation
Where there is only one convenient support, the “Inverted Vee” is a good antenna. It is simply a dipole with the centre attached to a support (tree, building, pole, etc.) The ends can be attached by ropes to a fence or temporary pole. Best performance is achieved with the antenna as symmetrical as possible, although there’s plenty of leeway. The Inverted Vee is less directional than a dipole, but you’re only likely to notice this at the higher frequencies.
The angle between the two halves is not critical, but 90° is the lowest reasonable limit. A simple calculation will show that an inverted-vee can take up about 75% of the garden space of a straight dipole, so a 33-foot antenna can be fitted into around 25 feet. But make sure that the ends are well clear of the ground, so that they cannot be touched by humans or animals. RF voltages at the end of a dipole can be high, even when using low power.
The Contest and your log
You should now be equipped to enter the RSGB IOTA Contest. Remember that the main objective is to enjoy yourself, and when you have had more experience, even get a certificate to hang on the wall. But you must submit your log first, within three weeks of the end of the Contest.
You will find that logging direct on to computer is preferable to logging on paper, particularly when it comes to checking "dupes". A straightforward program for carrying out this task is provided by EI5DI, and it will enable you to log as you go along in a very simple way. If you decide to log by hand, that is, on paper, you can use the same software to create your log afterwards, for submission and adjudication. See: www.rsgbcc.org/sd.shtml .
73, and good luck in the contest!
RSGB CC 2012
http://www.rsgbcc.org/hf/iotahelp.shtml
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