Short answer: The amateur bands do not have the same limits all over the world. The ITU divides the world into three Regions, the allocations on 160, 80 and 40 m differ between them, and your own licence can be narrower still. A QSO whose logged frequency lies outside the band can be questioned or removed when a contest log is checked, so look at the frequencies in your log, especially those near the edges. The figures here are general; check the current ITU Radio Regulations and your national rules.
Three Regions, three sets of limits
The International Telecommunication Union divides the world into three Regions for the purpose of frequency allocation. Region 1 covers Europe, Africa, the Middle East and northern Asia. Region 2 covers the Americas, and Region 3 covers most of the rest of Asia and the Pacific. Allocations to the amateur service are made for each Region, and for some bands they are the same everywhere while for others they are not. The low bands are where the differences are largest and where they matter most for contesters.
The national regulator then decides what its own licensed amateurs may use. A country may use the whole ITU allocation, a part of it, or add conditions such as power limits or modes, and different licence classes within one country may have different rights. The contest committee works with the general picture of the bands, but your licence is the real limit for your own operation, and the rules of the contest set the limit for the contest.
Approximate ITU allocations on 160, 80 and 40 m
The table shows the usual ITU allocations to the amateur service on three bands. Treat the numbers as an orientation only, because the Radio Regulations have footnotes and national variations, and they can change.
| Band | Region 1 | Region 2 | Region 3 |
|---|---|---|---|
| 160 m | 1810–2000 kHz | 1800–2000 kHz | 1800–2000 kHz |
| 80 m | 3500–3800 kHz | 3500–4000 kHz | 3500–3900 kHz |
| 40 m | 7000–7200 kHz | 7000–7300 kHz | 7000–7200 kHz |
On 160 m the difference is only at the lower edge. On 80 m and 40 m the upper edge is different in each Region, and Region 2 has the widest bands. In some countries parts of the allocation are shared with other services or available only on a secondary basis, and on 160 m many countries allow only narrower segments. The numbers above are not a licence.
Why the Regions matter in a contest
A contest brings together stations from all Regions on the same bands. European stations in Region 1 work North American stations in Region 2, and the allocations do not match. The upper part of 80 m and 40 m is available to one side and not to the other, so some stations cannot transmit where others are active. Stations that want to work them must listen where they cannot transmit, and the usual solution is a form of split operation or a special frequency range agreed by custom between the operators.
For the log, the important point is that a frequency which is correct for a station in Region 2 can be outside the band for a station in Region 1. A contest committee that checks a log from a European station sees a frequency above the limit and may take it as an error, even if the cause is only the frequency that the logger recorded. The article on the frequency field in Cabrillo shows how the field is written, and the QSO line explanation shows where it is in the line.
Why a QSO outside the band can be removed
A contest is held on the amateur bands, and an entry should contain only QSOs made within them. When a log contains a frequency outside the band, the committee has no way of knowing whether the transmission was really out of the band or whether the frequency was recorded wrongly. In general, committees treat such QSOs with caution, and the result can be that the QSO is not counted. The exact treatment is written in the rules of each contest, and it can also depend on the checking method. Check the current rules for what is said about operation outside the band and about frequencies in the log.
There is also a second consideration. Operation outside the limits of the licence is a regulatory matter between the operator and the national authority, and contest organisers can make it part of their rules that the entrant must follow the licence. A frequency recorded outside the licence is, at best, a log error and, at worst, evidence of a problem. It is better to find it yourself before the log is submitted.
Where band-edge problems come from
- Logger recording the receive frequency in split. At the edge, the receive frequency may lie outside while the transmit frequency is inside.
- Transverters and offsets. A wrong offset gives a frequency that is far from the real one.
- CAT problems. The logger does not update the frequency and keeps a previous value from another band.
- Typing errors. The frequency is typed by hand and a digit is wrong.
- Different units. The frequency is written in kHz in one place and in MHz in another, and the conversion fails.
- Real operation outside the band. The operator was in the wrong place on the dial, sometimes a few hundred hertz beyond the limit.
How to check your own log
The simplest method is to sort the QSOs by frequency in the logger, band by band, and look at the first and the last lines of each band. These are the lines nearest to the limits. A frequency that is a little beyond the edge, or one that does not belong to any band, is easy to find in a sorted list. If your logger has a function to filter QSOs by band, use it, and look for QSOs that are assigned to one band while the frequency belongs to another.
Then look at the QSOs close to the upper edge on 80 m and 40 m. If your licence ends below the Region limit, check against your licence and not against the table. For the stations you worked, do not worry about their frequency: the question is only what you transmitted and what your log says. If you find an error that comes from a logger setting, correct the cause for the next contest. The article about checking a contest log before you submit it puts this step in a wider routine.
What to do with a doubtful frequency
When a frequency looks wrong, do not simply change it to make it fit. Think about what happened at that time. Which band were you on? Was the radio in split? Was it the first QSO after a band change? An audio recording, if you made one, may help with the decision, and your notes may confirm the band. The article on recording audio in a contest describes how a recording can help with doubtful QSOs. If the frequency cannot be determined, think about whether to leave the QSO as it is or to remove it, and read the rules about corrections. A correction should be an honest one.
A small example
Imagine a European station in Region 1 that works a North American station near 3790 kHz on 80 m. The European station transmits at 3780 kHz, inside its own limit, and listens higher up, because the American station is calling there. If the logger saves the receive frequency, the line says 3790 kHz, which is above the Region 1 limit in the table. Nothing was wrong on the air, but the log now looks as if it was. A short note in your files about how your logger handles this, and a look at such lines before submitting, takes a few minutes and prevents a question that would be hard to answer months later.
Contest Analyzer and the edges
Contest Analyzer checks every callsign and every zone against official license databases and several independent reference sources and shows only the few QSOs worth a second look. You can edit calls or zones in the report and download a corrected Cabrillo. It also gives full statistics: rates, QSOs by hour and band, countries, continents, CQ and ITU zones, WPX prefixes, distance, beam heading, breaks and off time, and callsign length and structure, and allows comparison with your own logs from earlier years. It works with Cabrillo from N1MM Logger+, DXLog and Win-Test, supports 22 contests (see the contests page) and is available in 25 languages. The report also marks QSOs whose frequency is outside the band limits for your ITU region and shows when a QSO is probably split, so a stray frequency is easy to find and correct before you submit.
Related reading
The bottom line
Band limits depend on the ITU Region and on your licence, and a frequency outside them can cost a QSO or raise a question. Sort your log by frequency, look at the edges of each band and find the cause of any odd value. Read your licence and the current rules, not only a table.
FAQ
Are the limits of 80 m the same in all Regions?
No. The ITU allocations differ in the upper part of the band, and your national licence may be narrower still.
Can a QSO outside the band be removed?
It can be questioned or not counted, depending on the rules of the contest and the checking. Read the current rules.
Which table should I trust, this one or my licence?
Your licence and the current official rules. The table in this article is only a general orientation.
How do I find wrong frequencies in my log?
Sort the QSOs by frequency for each band and look at the first and the last lines, which are nearest to the limits.
Why does the logger sometimes record an odd frequency?
Split operation, an offset, a lost control link or a typing error can all produce an odd value.
