HAM Bands and Frequencies.

There is a good variety of ham bands or amateur radio allocations within the HF portion of the short wave spectrum. These ham radio bands or frequency allocations are open to radio hams around the world to use although the actual ham radio allocations do vary slightly from country to country and region to region. However a broad view of the ham radio band allocations can be given, and this is accompanied below with an overview of the properties of the different allocations for radio amateurs.

In the HF portion of the radio spectrum, there is a total of nine different bands that are allocated to ham radio around the globe. These bands are generally the same world-wide although there are some variations dependent upon the country or region dependent upon the actual amateur radio band in question. A summary of the different bands is given below.

136 KHZ BAND.

The 136 kHz band represents the lowest frequency amateur radio or amateur radio band. Although not allocated to all countries, this band is proving to be very popular with experimenters who are interested in LF band operating and the unique challenges it presents in ham radio.

The 136 kHz amateur radio band has only been available for radio amateurs in the past few years. With more countries releasing the band for ham radio use the level of activity is beginning to rise.

In view of its place at the very low end of the frequency spectrum, the 136 kHz allocation presents a unique challenge both in terms of operating and the technology that it used. Morse is generally used because it occupies very little bandwidth; several tens of Morse transmissions can be accommodated in this small band, whereas it is only wide enough for a single voice transmission. Many radio amateurs use very slow Morse combined with exceedingly narrow filter bandwidths and digital signal processing techniques. Also data transmissions are used, although the data rate that is used is again slow to reduce the bandwidth and also enable the signals to be received and deciphered despite their low level.

Full-sized antennas for these frequencies would be very large so radio hams use much smaller antennas. This presents new challenges for amateurs who use these frequencies.

Frequency allocation: 135.7 – 137.8 kHz

As this band is also allocated to other services in many countries 136 kHz is allocated on a secondary basis to ham radio users with the proviso that they do not cause interference to other services. Additionally the power levels are often limited. A typical power limit for the 136 kHz band is that used in the UK which limits the power to 1 Watt ERP (Effective Radiated Power). This for of power measurement is used because a full sized antenna at this frequency would be excessively large for virtually all ham radio users, and the small antennas normally used on 136 kHz have a very low level of efficiency because of their size. Accordingly the level of effective radiated power level is used.

While activity levels are still low on 136 kHz LF amateur radio band when compared to the very popular bands, interest is growing in this ham radio allocation and operating on these frequencies is particularly rewarding.

160 metres (Top Band)

UK Allocation
MHz
USA Allocation
MHz
1.810 – 2.000 1.800 – 2.000

Top Band is the lowest frequency ham radio allocation. Although it is termed one of the short wave bands and is often mentioned with the other HF amateur radio bands, to be exact it is actually in the MF portion of the spectrum.

Top Band is not allocated for ham radio use in all countries and the exact limits of the bands may vary. In general the maximum extent of any allocation fall between 1.8 and 2.0 MHz. In the UK, for example the lower limit of this ham band is 1.81 MHz.

With frequency of this ham radio allocation located just above the Medium Wave broadcast band, Top Band possess many of the same characteristics. As such it is used for relatively local ham radio contacts during the day when signals are heard via ground wave and, dependent upon transmitter powers and antennas, distances of 50 miles or more may be reached. At night, when the D layer in the ionosphere disappears, distances increase and it may be possible to hear stations several hundreds of miles away. For stations in North America and Europe, it is even possible to make transatlantic contacts when conditions are right if sufficiently good antennas are available at both ends. It is even possible to make contacts over longer distances.

For very long distance contacts on Top Band, the whole of the path must lie in darkness. However, there can be significant improvements at dawn and dusk for contacts with the other side of the globe. These enhancements may only last for 10 to 15 minutes at maximum, and sometimes less.

For shorter paths, like those between Europe and North America, signals peak when it is either sunrise or sunset at one end or the other. Long-distance, north-south paths often peak around midnight. As a general rule, long-distance work improves in winter because of the longer hours of darkness and lower levels of static. As this does not correspond with optimum conditions in the other hemisphere, it means that these signals may be heard at any time of the year.

80 metres (75 metres)

UK Allocation
MHz
USA Allocation
MHz
3.500 – 3.800 3.500 – 4.000

The 80 metre or 75 metre ham radio band is actually within the HF part of the spectrum. The actual allocation depends upon the radio region in which the country is located. Typically this can be 3.5 – 3.8 MHz, although in North America, frequencies up to 4.0 MHz can be used, although there is a broadcast band allocation above 3.8 MHz.

This ham radio band can be quite noisy, especially at night as it is shared with other services and this can make it very busy. Also the levels of static can be quite high.

During the day stations up to a few hundred miles away can be heard, making it an ideal band for medium distance contacts. At night ham radio stations from further away can be heard. Distances of over 1000 miles are very common, and greater distances can be achieved by those with good antennas. The band comes into its own during the years of the sunspot minimum, but it can perform well at any time.

Propagation along the grey line, i.e. the line along which dawn / dusk occurs) can produce exceedingly good results with stations from the other side of the globe being audible at the same strengths as many local stations. However, this may only be short lived and it can be very selective in terms of location. It is also best during spring and autumn.

Most of the ham radio SSB DX takes place in a ‘DX window’ in the top 25kHz of the European band. As a result this section of the band should be kept clear at all times. This should be observed even when it may appear there is no possibility of any DX coming through because stations with a good location and good antennas might just be able to hear DX stations.

Ham radio stations in North America and other areas of the world have an allocation up to 4.0MHz so it is common to work split frequency with stations who do not have this allocation, using the DX window below 3.8MHz for European stations and above 3.8MHz for North America etc.

40 metres.

UK Allocation
MHz
USA Allocation
MHz
7.000 – 7.200 7.000 – 7.300

The 40m amateur radio allocation is a particularly useful ham radio band, providing an interesting mix of short-haul DX by day and worldwide communications at night. In Europe the band is now 200kHz wide, although the section between 7.100 and 7.200 MHz may still have some broadcast stations present. In North America, where frequencies up to 7.3MHz are available, interference from European broadcast stations (to whom this portion is allocated) can be a problem.

During the day, stations up to distances of a few hundred miles can often be heard. Then at night the distances over which stations can be heard increases considerably, but local stations fall in strength. It is a favourite band for many during the low part of the sunspot cycle, being capable of long-haul contacts during the hours of darkness. Again the grey line can produce some spectacular results.

This ham radio band can be a good hunting ground for those with medium power transmitters and average antennas. It is found that comparatively few radio hams use directional antennas and this means that average amateur radio stations are at less of a disadvantage. Trap verticals, provided they are operated against a good earth or ground-plane system, can give a good account of themselves, allowing stations all over the world to be contacted.

30 metres.

UK Allocation
MHz
USA Allocation
MHz
10.100 – 10.150 10.100 – 10.150

This band was released for amateur radio use after the World Administrative Radio Conference held in 1979 (WARC 79). Although it has been available for many years now, it is still not very widely used although it but is capable of giving good results.

This ham radio band is very similar to 40 Metres and as a result it is capable of giving DX contacts for most of the day, although it is generally better at night, enabling ham radio contacts to be made around the globe Again conditions are enhanced by grey line and dusk or dawn conditions. It is also found that during periods of the sunspot minimum, when ionisation levels are lower, absorption is sufficiently low to allow long-distance contacts throughout the day.

Like the 40 metre ham radio band, this and the other WARC bands are good bands for the DXer who does not have a really big station. Few of the common directional Yagi antennas have this band and some stations may still be using linear amplifiers that cannot operate here. As a result it means that those with more average stations will be operating at less of a disadvantage.

Due to the small size of the band and the high level of commercial activity (because it is shared with other services), most of the operation is in Morse. In fact the IARU for Region 1 have recommended that contests and phone operation should be excluded from the band.

20 metres.

UK Allocation
MHz
USA Allocation
MHz
14.000 – 14.350 14.000 – 14.350

This amateur radio allocation is the main long-haul band for radio amateurs, reliably giving the possibility of long-distance contacts during all phases of the sunspot cycle. The band allocation is the same throughout the world, there being virtually no limitations where ham radio activity is permitted.

In terms of the performance of this ham radio band, during the day, stations up to about 2000 or 3000 miles can be heard when conditions are good, and there are virtually always stations between 500 and 1500 miles that can be heard. Often the band will close at night, especially during the winter and during periods towards the sunspot minimum. Spring and autumn normally produce good results, with stations from the other hemi-sphere being heard with ease at various times of the day.

Over the course of a day, signals can be heard from all over the world. In the early morning signals arrive from the east, and typically these will include signals from the other side of the globe. When these signals fade out, more local signals will become prominent, and there may be openings to the west as the Sun rises in that direction. As the afternoon wears on, openings further west may arise. There may also be openings to the other side of the globe again as their morning approaches. In the evening, as the levels of ionisation fall, the local signals will fall in strength, leaving long-distance stations to the west.

Being the mainstay ham radio DX band, 20m is often crowded and, when any rare amateur radio stations appear, the levels of competition are high. As a result many ham radio stations that frequent this band use good directional antennas that are mounted high up, combined with high transmitter powers. Some of the “big” stations run powers of the order of a kilowatt (where licensing conditions permit) and at least three element Yagi antennas at a height of around 60ft (20m). Nevertheless it is still possible to make many good contacts, but it is necessary to employ good operating techniques. Often when the conditions are good it may be necessary to assess the any pile-ups that are heard, deciding whether to preserve to make a contact with a particular station or whether to move on to find if there are any other DX stations with whom contact is more likely.

17 metres.

UK Allocation
MHz
USA Allocation
MHz
18.068 -18.168 18.068 -18.168

Like the 30m band, this one was released for amateur radio use after the WARC 79 conference. Accordingly some old transceivers may not cover this ham radio allocation.

In terms of performance, it is very much a half-way house between 15 and 20m. Although rather narrow, it is still very popular and well worth investigating when conditions look promising.

This ham radio band can offer some excellent opportunities for radio amateurs with more average stations to contact the rare DX stations. Although beam antennas are available for the band, most stations still use dipoles as those with beams may use them for the more traditional DX bands of 10, 15 and 20m, thereby limiting the number of strong stations. However, more antennas are appearing for the WARC bands with the result that more people are using these frequencies.

15 metres.

UK Allocation
MHz
USA Allocation
MHz
21.000 – 21.350 21.000 – 21.350

The conditions experienced on this amateur band are more variable than for the 20 metre band, being affected more by the state of the sunspot cycle. During the peak it is open during the day and well into the night when it will support propagation over many thousands of miles. Conditions are usually not quite so good in the early morning, improving as the day progresses. During the sunspot minimum few stations may be heard during the day and none at night..

At the top of the 15 metre ham radio band is the 13m broadcast band. It is possible to monitor this to gain a quick assessment of whether the amateur band may be open.

12 metres

UK Allocation
MHz
USA Allocation
MHz
24.890 – 24.990 24.890 – 24.990

This amateur radio band is the highest of the bands released for ham radio operation at WARC 79. As such it is not as widely used as the traditional bands including 20 metres, 15 metres and 10 metres, but it is still capable of providing some good results and it has a reasonable level of occupancy when compared to 15 or 10 metres.

Like 17m this band also is quite narrow but worth investigating when conditions mean the band could be open. Also, there are few stations using beam antennas and this makes it a good hunting ground.

10 metres

UK Allocation
MHz
USA Allocation
MHz
28.000 – 29.700 28.000 – 29.700

This is the highest-frequency amateur radio band in the short-wave (HF) portion of the spectrum. The allocation remains the same worldwide, and in view of its bandwidth (1.7 MHz) it is used for a variety of different modes of transmission including Morse, and SSB as well as FM, and there are even ham radio repeaters in some countries that are able to give worldwide coverage when conditions are good.

in terms of its properties, during the sunspot minimum it may only support ionospheric propagation via sporadic E which occurs mainly in the summer months. This gives propagation over distances of 1000 miles or so.

At the peak of the sunspot cycle it gives excellent possibilities for long-distance contacts, producing very strong signals. This band is well known for enabling ham radio stations with low powers and poor antennas to make contacts over great distances. In general, propagation on these frequencies requires that the signal path is in daylight. Despite this, at the peak of the sunspot cycle the band may remain open into the night, although it will eventually close.

Activity in the SSB portion of the band is often concentrated between the beacon section and 28.60MHz and a little above. However, it is worth taking a look above this, particularly in contests because stations may also be active in this sector.

Stations using low-power FM may be heard towards the top of the band. The recommendation is that FM activity should take place between 29.60 and 29.69MHz, with 29.60MHz as the calling frequency. There are some repeaters in the USA with outputs at 29.62, 29.64, 29.66 and 29.68MHz with inputs 100kHz lower.

Six Metres (6 Meters)

UK Allocation
(MHz)
USA Allocation
(MHz)
50.00 – 52.00 50.00 – 54.00

This is the lowest of the VHF ham radio bands, being very close in frequency to the HF portion of the spectrum. At the peak of the sunspot cycle worldwide communication is possible, with long-distance stations being heard at very good strength. However, at either side of the peak when the ionosphere does not support propagation at these frequencies, distances are normally much shorter and the band takes on a feel more akin to that of the other VHF bands. Even under these conditions sporadic E gives the possibility of long-distance contacts.

Four Metres

UK Allocation
(MHz)
USA Allocation
(MHz)
70.00 – 70.50 No allocation

This ham radio band of frequencies is only available for amateur operation in a very limited number of countries of which the UK is one. (More details of the exact number to whom it is available can be found at www.70mhz.org.) However, it has been recognised that an amateur radio band on this frequency would be of great benefit to the amateur community and there is a possibility that in the future this allocation might become more widespread.

Since there are very few countries active on this ham radio band there is little commercial equipment available, and this results in most of the equipment being either home built or ex-mobile radio equipment (from taxis etc) that has been modified for the band. This makes 4 metres very interesting and appealing to many radio amateurs.

Propagation is very much like that found on Six Metres although normal ionospheric propagation is rarely experienced. Sporadic E does produce some excellent results when it appears, although contacts with other countries often have to be on a cross-band basis, with stations from outside the UK transmitting on either 50MHz or 28MHz.

Two Metres (2 Meters)

UK Allocation
(MHz)
USA Allocation
(MHz)
144.00 – 146.00 144.00 – 148.00

This is the most popular of the VHF and UHF ham radio bands, especially where FM local and mobile operation is concerned. There is a comprehensive set of 2m repeaters that together cover large parts of the UK and other countries where operation is envisaged. There is also a large level of data (packet radio) activity. For those interested in long-distance contacts there is also SSB and Morse activity which rises significantly during contests or when propagation conditions are good.

The ranges that can be achieved often depend very largely on the antenna, transmitter power and location. However, for most stations distances of at least 30 to 50km should be possible.

Those ham radio stations with high powers, good antennas and a good location will be able to reach much greater distances, especially when using SSB or Morse. When conditions on the band improve as a result of tropospheric propagation distances up to 1000km can be reached on occasions, and with sporadic E it is possible to make contacts over distances of some 2000km. However, this is the highest frequency ham radio band where sporadic E can be experienced.

Operation on FM is channelised. This makes it much easier to locate a particular frequency, especially when operating mobile. It also reduces the level of interference because channels are spaced such that a station on one channel does not interfere with one on the next. A system of channels spaced by 12.5kHz is replacing the previous one where channels were spaced by 25kHz.

1.25 Meters

UK Allocation
(MHz)
USA Allocation
(MHz)
No allocation 219.00 – 220.00
222.00 – 225.00

This ham radio band is allocated in the USA but is not available in Europe. The bottom sector of the band (219.00 – 220.00) is available for fixed digital message forwarding systems only, whereas the top section is subject to the more usual restrictions and dependent on the licence class held by the licensee.

This ham radio band is popular for FM use. Its character is quite similar to that of two metres in terms of propagation. However, Sporadic E is seldom experienced on this band although it has been known.

Seventy Centimetres (70 Centimeters)

UK Allocation
(MHz)
USA Allocation
(MHz)
430.00 – 440.00 430.00 – 450.00

The Seventy Centimetre ham radio band is very popular for local and mobile communications like many of the lower frequency VHF bands including 2 Metres. There is an excellent network of repeaters in the UK and many other countries, enabling a good variety of contacts to be made even when only hand-held or mobile equipment is available.

Ham radio contacts can be made at distances of 30km and more with an average fixed station, and more if good antennas are used. For those wanting to make longer-distance contacts, SSB and Morse are better than FM. Although activity levels on these modes are often low, they increase dramatically during contests or when conditions are good.

Tropospheric propagation is the most commonly used way in which long-distance contacts are made, although other techniques including satellites and moonbounce can be tried. However, moonbounce is really a specialised technique.

Like 2 Metres, 70 cms has a large amount of FM operation for which channels are assigned. These have a similar method for assigning the channel designations. Although operation is not currently migrating to a channel spacing of 12.5kHz, new designations are being introduced that can accommodate this spacing. Again, the old channel designations are shown in brackets. Most repeater operation uses a 1.6 MHz spacing between input and output channels, although some are expected to use the 7.6 MHz split more commonly used on mainland Europe.

33 Centimeters

UK Allocation
(MHz)
USA Allocation
(MHz)
No allocation 902.00 – 908.00

Like the 1.25 meter ham radio allocation, the 33 centimeter band is also not available in Europe as it falls within the cell phone allocations. However within North America it is a popular band as it falls just below 1 GHz and it has some useful propagation properties.

23 Centimetres (23 Centimeters)

UK Allocation
(MHz)
USA Allocation
(MHz)
1240 – 1325 1240 – 1300

The 23 cms ham radio allocation is becoming more popular with the advent of commercially made equipment. Even so there are currently less amateur radio stations on it than on 70 centimetres.

23 cms gives plenty of scope for experimentation and it is capable of producing some surprising DX when there is a lift. Location is particularly important for DXing and as a result many stations will operate portably from local high spots for this reason. It is also found that paths across the sea are better than those across the land.

13 Centimetres (13 Centimeters)

UK Allocation
(MHz)
USA Allocation
(MHz)
2310 – 2450 2300 – 2310
2390 – 2450

There is little commercial equipment for the 13 cms ham radio band at the moment, but it is likely that this will change before too long. Currently the band is used by a number of ham radio enthusiasts and a reasonable number of contacts can be made. During contests activity increases dramatically and, like 23 centimetres, it is possible to make contacts over surprisingly long distances.

As this band is virtually a microwave band the technology which has to be used reflects this. For example, parabolic reflector or “dish” aerials are commonly used.

In view of its frequency, this frequency allocation is greatly affected by the position of the sunspot cycle and it has many similarities with 10 metre ham radio band.

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