This page is designed for people new to Amateur Radio or VHF long distance (DX) communications.

When I was first licensed as a Radio Amateur in 1985, with my then VHF only callsign of G1MOG, I had already spent 2 years as a Short Wave Listener (SWL) listening to the Amateur Radio HF and VHF bands, with QSOs (conversations) heard from all round the World. This time was well spent as it taught me a lot of procedure, etiquette, and  operating practices, before I ever transmitted when I became licensed to. Since passing the 12wpm Morse Code test in 1987 I have held my FULL licence callsign G0ISW.

The same is true for those of you who are newly licensed, or new to VHF DX, as time spent listening before you ever transmit will be time well spent and will avoid you making unnecessary mistakes, rather like the characters from 'Wallace & Gromit', who mean well, but sometimes do silly things whilst they experiment with new inventions and ideas. Believe me, every Radio Amateur makes mistakes at some time.

           

 

If you cannot see the full index shown on the left edge of your screen, please go to my main page at http://www.qsl.net/g0isw

 

If you have no existing Amateur radio or short wave receiver and want to 'simulate' the HF (worldwide) amateur radio experience, then you could try downloading and using the new 'Hamsphere' software (you do not require an amateur radio licence). I haven't tried this yet myself, but it seems an easy and cheap way to see if you would ultimately like to invest in a real radio and become a Radio Amateur or Short Wave Listener (SWL).

 

 

 

 

 

 

 

Here in the UK there are currently 3 different classes of Amateur Radio license

M6

2E0

M0

               

Each class of license requiring different levels of technical and practical knowledge and each having different permissions for frequencies and power levels. The old requirement of having to pass a 12 wpm morse code examination, before access to the HF bands was permitted no longer exists, so now it is easier than ever to become licensed. The Foundation license, for example, requires you to attend about 10 hours on a training course, spread over several weeks (or a weekend) and after passing you will be allocated a M6 plus 3 letter callsign and will be able to get on the air and talk to people around the World.

Did you know that it is now possible to listen to Amateur Radio and Shortwave signals without having a radio? Thanks to the internet you can use your home computer to link to other people's radios and listen, without costing you a penny! Simply click on the Global Tuners image below and follow the instructions.

 

 

 

I will describe below how you can move on from simple line of sight (short range) 144 MHz FM QSOs at VHF, to working Long distances (DX) and using new more complex data modes. This is based upon my own experiences of the last 25 years.

 

 Essential links for new starters

Latest UK Band Plans UK Repeater Listing Introduction to VHF & UHF propagation

Amateur Radio Courses & Exam Centres

European VHF/UHF Contest Calendar Radio Society of Great Britain
 RSGB Data Communications Committee

Amateur Radio licensing

Satellite FAQ & intro articles

 FDS QSL cards

Euro Grid Square Map

VHF/UHF Line of sight calculator

 Maidenhead Locator Finder

 

 

 

 

 

 

50 MHz is probably the easiest VHF band to achieve regular long distance (DX) communications (Summer only), but radio conditions can vary tremendously depending on the time of year and the solar cycle.

The best time of year is from May to August during the Sporadic Es season, where with low power and simple aerials anyone in the UK can work most of Europe, up to 2,300km distance from your station, and with very strong signal strengths in both directions. However, outside of the summer months conditions can generally be poor and the band appear totally deserted. There are exceptions as at the maximum of the solar cycle 50 MHz signals are reflected by the F2 layer just like on HF and it is possible to work all continents including Australia! The pileups can be frustrating to break though.

Also it is possible at all times of year to work stations in Europe up to 2,300km away by bouncing your signals off the ionised trails left by meteors entering the Earth's atmosphere. You will need WSJT software and a computer linked by a soundcard interface to your USB transmitter, but there is plenty of Meteor Scatter activity, most mornings and evenings, around 50.230MHz using JT6M mode. You will also need a directional aerial.

N.B. 50MHz is considered poorer than 144MHz for Tropo Scatter communications, which are available day or night for ranges in the region of 100-500 Km.

 

 

New to Amateur Radio? Start on this band for local contacts either simplex or through repeaters.

 

 

144 MHz is the mainstay of VHF amateur bands around the World. Most Radio Amateurs will have a handheld or small mobile radio capable of transmitting on the 144 MHz (2m) band, which is where most local VHF activity will be found. If your radio is only capable of FM transmissions, then until recently you had fairly limited options for working further than very local distances in the order of 0-50km. This is because at VHF, signals are 'line of sight' and are blocked by obstructions such as hills, buildings, trees etc. Also because of the curvature of the Earth's surface your signal will eventually disappear into Space, unless reflected back by something. 

In the UK the 2m calling frequency is 145.500 MHz FM, listen for CQ calls and respond or call CQ yourself, but move away from the calling frequency to continue your conversation as soon as you can. The 'S20' shown after 145.500 MHz on the listing below relates to the 'old' original UK system of numbering 2m simplex channels, which is still used by many amateurs as the newer system of numbering channels following the move away from 25kHz channel spacing to 12.5 KHz channel spacing is too complicated for most to understand and use. Often you will hear stations saying 'QSY to S23'which means move from the calling frequency to 145.575 MHz for example.

145.300 (S12)

145.325 (S13)

145.350 (s14)

145.375 (S15)

145.400 (S16)

145.425 (S17)

145.450 (S18)

145.475 (S19)

145.500 Calling channel (S20)

145.525 (S21)

145.550 (S22)

145.575 (S23)

In Cities there can be a lot of activity on simplex channels between 145.300 - 145.575 MHz but often there is more activity on repeaters which retransmit signals from high locations and cover greater areas. In the UK the repeater channel outputs on which you listen are from 145.600 MHz - 145.775 MHz, with -600kHz offset, so you transmit on a slightly lower frequency. For example for my local repeater GB3EV the output is on 145.700 MHz and the input is on 145.100 MHz.

If the repeater is 'open' after a station's transmission is over, the repeater will signal by a tone or pip that it is ready to retransmit a new signal. Wait for this otherwise the repeater timer isn't reset and after approximately 2-5 minutes the repeater will switch off and go into standby mode.

To 'open' a repeater that is in standby mode, you need to either transmit a single 1750Hz tone before you speak (old fashioned way of doing this) or you need to transmit a sub audible CTCSS tone on the correct setting for your area, click on link below to see map. UK 2m repeater CTCSS tone map You will also need to see what frequency your local repeaters are on so click on this link Full UK repeater list

 

 

To achieve reliable long distance (DX) communications on this band you will need a multimode radio, at least 25 watts and a directional yagi type aerial, that can be turned with a rotator. Contrary to popular opinion you do not need the maximum permitted 400 watts and a massive 17 element yagi, but if you have this available then obviously it will be superior to a smaller setup. I only use 50 watts and a small Log Periodic antenna which is only 3m long, but have still managed to work North Africa on 144MHz USB via Sporadic Es as well as Estonia and Iceland via Meteor Scatter from England.

 

432 MHz can be a very frustrating band. Long distance communications are possible via Tropo Ducting, which appears when there is very high air pressure and no wind, often with fog present, but if there are mountains in the way they will block this.

When I lived in London, which is fairly flat and has a good view to the horizon, I could work Switzerland with 10watts and an ex-military phased array of 16 dipoles. Since moving to the Lake District in 1990 the furthest distance that I have achieved has only been around 200km via Tropo Scatter. The mountains simply block all Tropo Ducting for me as I live in the valley floor.

In 2006 there was a fantastic Tropo Ducting opening from the UK to Scandinavia, which we could hear from the top of the Pennine hills 20km to the East of my QTH, but as soon as you drove slightly down the hill they all disappeared.

There are other methods of achieving long distance communications on this band such as Satellites or Moon bounce (EME), but this can get very complicated and often may require an elevation rotator and extensive antennas. Signals on 432 MHz are much weaker than on 144 MHz. It is however a good band for mobile repeaters using FM and the UK has an extensive network in most areas.

 

Which VHF/UHF radio is the the one to have as a base station for DX work? Well, I have tried several and would currently recommend either the Yaesu FT-847, Icom 746/7400 or my current radio the Kenwood TS-2000.

The sensitivity of the Yaesu FT-847 is particularly good and they can also transmit on 70 MHz, but are rather deaf on that band. The HF side of the radio is basic with no internal ATU though. The VHF/UHF power output is a maximum of 50 watts, but on 70MHz varies from 10w to 25w depending on batch number.

The Icom 746/7400 is an excellent HF radio and has respectable performance on both 50 MHz and 144 MHz, but lacks the ability of cross band 144/432 MHz required by some satellites. It has an internal ATU for HF and 50 MHz and has 100 W on all bands including 2m.

The Kenwood TS-2000 is good on both HF, 50 MHz, 144 MHz, 432 MHz and can be fitted with 1296 MHz too! It has an internal ATU for HF and 50 MHz. Its one fault is that all models apparently have an internally generated carrier signal on 435.300MHz, which is a downlink FM frequency used by a number of amateur radio satellites. The Kenwood was unique in that it was one of the first to be able to be upgraded through software downloads.

 

 

Your antenna height above sea level will affect how far your signal can travel, try the VHF/UHF Line of sight calculator by G4VWL to see for yourself how far your signals can travel from home via conventional line of sight propagation. Don't be concerned that you do not live at a great height above sea level! This will only affect your ability to work greater line of sight distances up to a maximum of 100km, even more important is your ability to have an unobstructed view of the horizon. Believe me it is better to be located in Norfolk than amongst the mountains of the Lake District, from a VHF DXer's perspective.

                          

Height km

VHF Propagation modes

Different propagation modes enable VHF/UHF signals to travel further than normal 'line of sight' because they are reflecting your signals from different heights, above sea level, in the Earth's atmosphere.

Tropo Scatter takes place below 10,000m (10km) height (Mt. Everest is by comparison 8,850m high), whereas the majority of Meteor Scatter takes place at 90km altitude and Sporadic Es can be up to 110km height, allowing much greater distances to be achieved.

The exception is Tropo Ducting, between 450-3000m height asl, where the signals are trapped between layers of hot and cold air (temperature inversion) and if over a good calm sea path may extend for huge distances. Contacts between Scotland and the Canary Islands on 144MHz have been achieved this way.

Why are Auroral signals shown to typically achieve a lesser distance than Meteor Scatter even though the reflection takes place at a greater height in the Atmosphere? They do actually travel further reflected off the Auroral curtain near the Arctic and back again, but the receiving station may be a lot closer to you in Europe.

The International space Station and the Space Shuttle are both over 200km in height.

VHF/UHF Propagation modes explained

Propagation type

Distances

Comments for European stations

Line of sight

0-100km

This is the mode by which most of your local 144/432 MHz FM simplex conversations will be made, either direct to stations or via repeaters.

Dependant upon antenna height above sea/ground level and visible radio horizon distance. Line of sight (LOS) distance can be increased with height or decreased by obstructions such as mountains, buildings etc.

Line of sight is the direct free-space path that exists between two points. Using binoculars on a clear day, it is easy to determine if visual line of sight exists between two points that are miles apart. To have a clear line of sight there must be no obstructions between the two locations. Often this means that the observation points must be high enough to allow the viewer to see over any ground-based obstructions.

The following obstructions might obscure a visual link:

  • Topographic features, such as mountains

  • The curvature of the Earth

  • Buildings and other man-made objects

  • Trees

If any of these obstructions rise high enough to block the view from end to end, there is no visual line of sight.

Obstructions that can interfere with visual line of sight can also interfere with radio line of sight. But one must also consider the Fresnel effect. If a hard object, such as a mountain ridge or building, is too close to the signal path, it can damage the radio signal or reduce its strength. This happens even though the obstacle does not obscure the direct, visual line of sight. The Fresnel zone for a radio beam is an elliptical area immediately surrounding the visual path. It varies in thickness depending on the length of the signal path and the frequency of the signal. 

As shown in the picture above, when a hard object protrudes into the signal path within the Fresnel zone, knife-edge diffraction can deflect part of the signal and cause it to reach the receiving antenna slightly later than the direct signal. Since these deflected signals are out of phase with the direct signal, they can reduce its power or cancel it out altogether. If trees or other 'soft' objects protrude into the Fresnel zone, they can attenuate (reduced the strength of) a passing signal. In short, the fact that you can see a location does not mean that you can establish a quality radio link to that location.

 

There are several options to establish or improve the line of sight:

        Raise the antenna mounting point on the existing structure

        Build a new structure, i.e. radio tower.

        Increase the height of an existing tower

        Locate a different mounting point, i.e. building or tower, for the antenna

        Cut down problem trees

 

Click on this link for VHF/UHF Line of Sight range calculator.

 

Knife edge diffraction

1-100km

Your LOS signal, which can be blocked by high terrain can sometimes be diffracted or bent over the top of the obstruction, particularly in mountainous areas if the top of the obstruction is 'sharp', hence the term 'Knife-edge diffraction'.

More information and software calculator here

I live in a mountainous area and have experienced a few instances where contacts have been made with stations that should have been totally obstructed by high mountains in between.

 

Tropo Scatter

100-500km

This propagation mode is available all the time and is the main one for longer contacts, particularly at 144 MHz on SSB within the UK or to mainland Europe. Slow fading of signals often apparent and reasonable signal strengths.

This propagation mode was used by NATO, from around 1956 to the late 1980's, as part of the ACE HIGH Troposcatter system on frequencies between 832 MHz and 959 MHz, in a chain of 49 stations running from Norway to Turkey. Transmitting power was around 10 KW and huge dish antennas were used!

I remember seeing the huge dishes at Cape Greco (JCGZ) in SE Cyprus in the late 1980's, but am struggling to find any photos of them apart from this one.

Looking at Google Earth imagery below, from 2003, it appears the dishes have now been removed.

 

Aircraft Scatter

100-500km

Aircraft scatter propagation is subject to rapid fading of signals and not particularly easy to catch or use. You can liken it to bouncing your radio signals off the metal aircraft body, which will be travelling extremely fast, in the same way you would bounce light off a mirror.

RADAR (Radio Detection And Ranging) has used radio signals since before WW2 to determine the flight path of aircraft. Early German WW2 radar used frequencies near to the amateur 144 MHz band. Modern stealth aircraft such as the US Air Force F-117 were designed so that their shape would not easily reflect Radar signals back to the receiving station, by avoiding having any vertical angles.

 

Some experimentation has been done by SM6FHZ and his website detailing how to work regularly via this mode, using flight timetables is here. Frequencies of 144 MHz, 432 MHz and 1296 MHz have all been used successfully. Some imagery and an explanation of how you can experiment to listen yourself can be found on the website of G3CWI here.

 

Aurora

250-1100km

 

Aurora favours Northern Europe. March is often a good month. You need to point your antenna between North and East and reflect your signal off the moving Auroral curtain.

Speak much slower than normal and compensate for the Doppler shift, which makes everyone sound like Daleks!

 

50 MHz is particularly good for this mode, 144 MHz is useable and 432 MHz is extremely difficult due to the high Doppler shift.

More information can be found here.

 

FAI

 

 

 

 

 

 

250-1100km

 

 

 

 

 

 

Field Alignment Irregularities (FAI), can occur in the late afternoon from May to August, and favour Southern Europe. The signal is usually very weak and the scatter area is located at a height of approximately 110km.

 

TEP

3000-8000km Trans-Equatorial Propagation (TEP)

During exceptional VHF openings some amateurs worked DX stations located 8000 km away crossing the Equator. Imagine:  From Southern Europe to South Africa on 50MHz or even 144MHz ! This phenomenon seems to occur when both stations are located at equal distances North and South of the Equator and experiencing a high level of electron density in Autumn and Spring, during periods of solar maximum activity and the equinoxes.

The stations located over 45 of latitude north (or south) are usually too far off the geomagnetic equator to make use of F-layer FAI. Sometimes however, these latitudes can be worked via an additional sporadic-E hop, even if signals are usually weak and typically exhibit the fluttery and hollow like sound of pure FAI.

It was observed that there were two distinctly different types of TEP that could occur:

The first type occurred during the late afternoon and early evening hours and was generally limited to distances under 6000 km. Signals propagated by this mode were limited to the low VHF band (<60 MHz), were of high signal strength and suffered moderate distortion (due to multipath). Single sideband voice communications were possible with this mode.

The second type of TEP occurred from around 1900 to 2300 hours local time. Contacts were made at 144 MHz, and even very rarely on 432 MHz.

The signal strength was moderately high, but subject to intense rapid fading, making morse code (narrow band CW) the only possible communication mode. One amateur described the signal quality in the following words: "we tried SSB but there was so much distortion that not a single word could be identified. [this mode] has a lot of flutter and fading and ... even the morse comes through like a breathing noise, not a clear tone" (from the Dawn of Amateur Radio in the UK and Greece by Norman F Joly).

 

Tropo Ducting

200-1000km

Signals can be quite strong. Look for periods of high air pressure over the UK and Europe. Often extensive fog can indicate the right conditions for this propagation mode. Once established paths can be open for many hours or days. Often you may hear far away 144 MHz/432 MHz repeaters that normally cannot be heard.

Sea path possible exceptionally up to 3000km on 144MHz SSB, paths between Scotland and the Canary Islands have been worked. October often the best month. These Ducts form at heights between 450m to 3000m, but are blocked by higher mountains along the path.

Click here for atmospheric temperature soundings.

Select Europe map and then click on site to view readings. Gif image to 700mB best. Look for temperature inversions, where the inversion thickness layer is wide enough to support ducting at 144 & 432MHz, using the table below.

Inversion thickness required
Feet
Metres
Band
MHz
300
91
UHF
432 MHz
600
183
VHF
144 MHz

 

Ionoscatter

900-2000km

Not commonly useable by radio amateurs. Ionoscatter is the scattering of radio waves in the ionosphere due to irregularities in the electron distribution, which causes changes in the refractive index. Scattering is most pronounced in the D-region between 70 and 90 km and is best from 30-60 MHz.

Ionoscatter is a propagation mechanism available 24H a day like meteor scatter, but it is different from meteor scatter. Ionoscatter deliverer's a continuous weak signal and does not have the characteristic bursts in signal strength of meteor scatter.

Ionoscatter starts about 900 km and extends to almost 2,000 km. Troposcatter works on all frequencies 50 MHz to 10 GHz, whereas Ionoscatter is only useable on 30-60 MHz.

NATO Military radio systems from around the years 1950-1960 used huge aerials and around 40kW of power to maintain reliable signals via this mode! The Distant Early Warning Line DEWLine being a good example. Therefore it is rare for Amateur Radio transmissions to be powerful enough to utilise this mode. The Military Ionoscatter system was replaced by Troposcatter systems in the 1960's.

DEWLine station in Alaska

 

 Meteor Scatter

 

 

 

700-2350km

Summer months best for major showers, but winter months active too. Random meteors occur all the time day or night. Can be a mode that can revolutionise 50/144 MHz SSB contacts using WSJT software for long distance contacts. My favourite mode!

Reflections of radio signals can last from around 250 milli seconds (1/4 of a second) to 30 seconds plus, but the vast majority are extremely brief. It usually takes a long time to complete a QSO in the region of 30 minutes or an hour, unless there is a major Meteor shower such as the Leonids in 2001.

To easily hear Meteor pings tune your transceiver to a strong Band 1 TV station video carrier such as 48.242.2 MHz CW or 49.739.7 MHz CW and you will hear nothing, until the signal is reflected briefly by a passing meteor! Please note that during the Summer months Sporadic E (Es) may allow you to hear the TV carrier continuously.

Unfortunately Band 1 analogue TV is being phased out in Europe and so the availability of these TV carriers is being much reduced for monitoring Meteor Scatter. There are some alternatives, such as the French GRAVES space surveillance radar system on 143.050 MHz CW.

 

 

Sporadic E (Es)

50MHz  

500-2350km

(Single hop)

 

 

1000-4700km

(Double hop)

 

 

 

 

 

Around 6000km

(Triple hop Sp-E or SSSP)

 

Sporadic E (Es) at mid-latitudes occurs mostly during summer season, from May to August in the Northern hemisphere and from November to February in the Southern hemisphere. Very strong signal strengths are common.

There is no single cause for this mysterious propagation mode. The reflection takes place in a thin sheet of ionisation around 90 km height. The ionisation patches drift westwards at speeds of few hundred km per hour. There is a weak periodicity noted during the season and typically Es is observed on 1 to 3 successive days and remains absent for a few days to reoccur again. Es do not occur during small hours, the events usually begin at dawn, there is a peak in the afternoon and a second peak in the evening. Es propagation is usually gone by local midnight.

Sporadic E (Es) clouds have been observed to initially occur within approximately 150 km (90 mi) to the East of a severe thunderstorm cell complex in the Northern hemisphere, with the opposite being observed in the Southern hemisphere. To complicate matters is the fact that Sporadic E (Es) clouds that initially form to the East of a severe thunderstorm complex in the Northern hemisphere, then move from ESE-WNW and end up to the West of the severe thunderstorm complex in the Northern hemisphere.

So one has to look for Sporadic E (Es) clouds on either side of a severe thunderstorm cell complex. Things get even more complicated when two severe thunderstorm cell complexes exist approximately 10002000 miles apart.

Not all thunderstorm cell complexes reach severe levels and not all severe thunderstorm cell complexes produce Sporadic E (Es). This is where knowledge in Tropospheric physics and weather analyses/forecasting is necessary.

 

 

50MHz 2,350km is max single hop distance. 50MHz Sporadic E (Es) season is from May to August in the Northern Hemisphere. Double hop often seen vastly increasing the distances worked.

Some distances worked when at solar minimum in 2007 have been in the order of 6000km, is this triple hop Sporadic-E or something else such as Short-path Summer Solstice Propagation (SSSP)?

 

144MHz

1400-2350km

(Single hop)

 

 

Around 3000km

(Double hop)

144MHz 2,350km is max single hop distance. 144MHz Sporadic E (Es) season is from June to July in the Northern Hemisphere.

 

Rare double hop Sporadic-E up to around 3000km perhaps with ground reflections from large inland waterways such as lakes and rivers as one theory suggests.    Click on link for more information.

F2 layer

50MHz

>3200km

Only open on 50MHz towards the peak of a solar cycle, in the Winter months from October to April, but possible to work all Continents including Australia. Next peak due in 2012/2013. Get ready for the pileups!

 

 

 

 

VHF DX Year Planner

 

 

In the UK the 2m calling frequency is 145.500 MHz FM. This is where you would listen to hear someone calling 'CQ' which means they want to have a conversation with anyone, or you might hear them call 'CQ DX', which means they want a conversation only with someone who is a long distance away from them. If they call 'G9ABC from M9ABC' then they only want to speak to 'G9ABC' and not you. Once you are confident enough you can call 'CQ' and someone will hopefully reply to you. Then you have to QSY (change frequency) away from the calling frequency to a clear frequency. Always listen and ask if that new frequency is in use, the UK Bandplans should always be adhered to.

                                                       

 

You may now have spent some time speaking to other local Radio Amateurs and you now want to work stations further afield. One option is to work through a repeater, which will retransmit your signals. Another option is to improve your 'line of sight' to other stations, which can simply be achieved by getting your aerial as high as possible. At home this might involve something simple like attaching an aerial to your chimney or installing a mast onto which you can place an aerial. 

I used a Tennamast telescopic tilt over mast, which allows me to attach new aerials or cables at ground level before I wind the mast up to its 10 Metre height, which clears the top of my house. Another form of repeater are the Amateur Radio satellites, some of which are FM and allow communications using a handheld radio with other stations around the World. Satellite FAQ. The International Space Station (ISS) also regularly has crew members who are licensed radio amateurs.

 

                       

 

When not at home, another option of improving your aerial height is either by driving your car to a hilltop or walking to the top of a hilltop. With a 2m handheld radio and 1 watt of FM for example, from a 3000' hilltop, it is fairly easy to work distances in the region of 0-125 km without using a repeater! Activating hilltop summits has become very popular recently and more information on this subject can be found on my SOTA page. 

 

 

Sometimes you can experience VHF DX communications due to unusual Propagation. Probably the best example of this is Tropo Ducting, where following a period of sustained high air pressure over the UK, around 1030mb, signals from the Continent, or far flung parts of the UK, can be heard at strong signal strengths. This used to occur quite frequently in October of each year, but can occur at any time. FOG and High Pressure on Weather maps can help to identify likely occasions.

Distances achievable are in the region of 200-1000 km, but with a good sea path distances of up to 3000km have been achieved between Scotland and the Canary Islands. The best times of year are the Spring and Autumn. In the weather chart shown below there is not an area of equal pressure between Scotland and the Canary Islands, so that tropo ducting between the two would not be possible.

 

 

In addition to speech on 144 MHz FM it is easily possible to use some data modes for communications too. I used to use RTTY in the 1980's on the 145.300 MHz FM frequency and had great fun seeing messages from other Radio Amateurs appearing on my computer screen as they typed each key. Advances in computers and software have made it possible to connect your 144MHz FM radio to your computer and experiment with all sorts of data modes including Slow Scan Television (SSTV). It is also possible to connect to other Amateur stations around the World using your radio and/or computer and Internet Linking which is the latest development in the hobby with free software such as EchoLink.

  

 

 

For really serious VHF DX though, you will need a multimode transceiver capable of Single Sideband (SSB) transmissions and you will also need a horizontally polarised beam antenna, which has significant gain compared to a dipole. Probably the best and most commonly used is a Tonna 9 element beam. Ideally you will also need a rotator so that you can point your aerial at the station or Country you are trying to work/hear. 

An essential question you need to be able to answer is your Maidenhead Locator square, as this is the information, which allows amateurs to determine your location anywhere in the World and is used for Award purposes. Use either Maidenhead Locator Finder or QTH Locator converter to find yours and look at Euro Grid Square Map to see the locations of other Amateurs.

Lots of us use DXclusters and a link to the Internet to find DX stations more easily. A nice piece of software that I have used is DX Monitor

  

 

Using your multimode radio in Upper Side Band (USB) and calling initially on 144.300 MHz it is possible daily to have speech contacts in the region of 50-500km using Tropo scatter propagation, depending on where you are in the UK you may be able to have regular QSO's with amateurs in Europe.

 

 

                   

 

During the months of May to August you may be very lucky to experience a rare form of propagation called 'Sporadic E', which can appear from nowhere and allow you to work vast distances. Distances achievable are in the region of 1100-2350km on 144MHz

I have managed to work North Africa, EA9IB on 144MHz USB with only 25 watts and a small Log Periodic aerial (equivalent to a 4 element yagi) via this mode. A distance of 2154 km.

Once you have worked DX using speech and SSB and are familiar with chasing DX, it becomes a challenge to collect and work new Maidenhead locator squares and Countries. A very good piece of software for keeping track of your VHF achievements is VQlog 3.0B

 

 

 

When you are really struggling to find any new locator squares because you have worked all the ones close to you then you can try Meteor Scatter, which is where I am concentrating now, but it requires considerable skill to be successful. Distances achievable are in the region of 500-2200km. You will need to download the fantastic WSJT software and use this in conjunction with a computer to transmit high speed data over your radio, which can be decoded at the receiving end, for meteor reflections lasting typically less than 1/4 of a second!

Station A      Station B

 

Frequency Digital MS mode  Remarks
50.230 MHz USB (JT6M)  Calling frequency
50.270 MHz USB (FSK441)  MS calling frequency
50.260-50.280 MHz USB (FSK441)  
70.100 MHz USB (FSK441)  Proposed MS calling frequency
70.090-70.110 MHz USB (FSK441)  Proposed
144.370 MHz USB (FSK441)  MS calling frequency
144.360-144.400 MHz USB (FSK441)  
432.370 MHz USB (FSK441)  MS calling frequency
432.360-432.400 MHz USB (FSK441)  

  My top tips for WSJT software are:

 

 

The excitement of communicating with an Astronaut onboard the International Space Station or speaking through an Amateur Radio satellite to someone thousands of km away is good fun, but it can be daunting for the beginner. You do not need to have an antenna system that is steer able and has elevation control, but it does help, also you do not need to have automatic satellite tracking or Doppler frequency control for your radio however you will be at a disadvantage if you do not.

I will describe below how it is possible with modest equipment to have some success. You should start by visiting the AMSAT satellite status to establish the current operational status of the Amateur Radio satellites. The easiest to work will be the Low Earth Orbiting (LEO) satellites which have 2m and 70cm FM uplinks and downlinks, currently these include AO-27, SO-50, AO-51 and the International Space Station.

You will need to identify the uplink and downlink frequencies and programme your radio accordingly, also some of the uplinks require a PL or CTCSS tone too.  Next you need some satellite tracking software to determine when these satellites will be within range of your station, I can recommend either SatScape 2.02 or SATPC32 software. Both programmes download the latest Keplarian elements automatically, from the Internet.

Now you will know when these satellites will next be in range. Listen to them first and observe the operating procedure of other Radio Amateurs, you can use any sort of aerial including a collinear for this purpose. Once you are comfortable with what to do, you can try working your first satellite, but it requires patience, for example when the International Space Station is in range of you, its footprint may cover most of Europe and numerous other amateurs will all be calling at the same time as you! That is all part of the challenge, and remember that some Hams have just used their handheld radios and have been successful.

If you really want to work satellites properly, you might want to use either a Yaesu FT-847 or Kenwood TS-2000 transceiver, which are both designed for this purpose and have all the bells and whistles required.

The ultimate VHF/UHF DX has to be bouncing your signals back from the Moon (EME). With this mode it is possible to work stations in other Continents, but it requires large antenna arrays, high power and suffers from very weak reflected signals.

In early 2006 I became interested in working the International Space Station, Low Earth Orbiting Amateur Radio Satellites and trying EME (using the JT65B digital mode). This has come about because band conditions are so poor on HF at present and realistically I have worked as much as I can via the normal VHF/UHF propagation modes. I am however finding it a very steep learning curve.

I use Nova for Windows software to give me audible alerts in the shack, when the Satellites are coming into range. I use SATPC32 software to CAT control my Kenwood TS-2000 radio and correct my 144MHz and 432MHz speech signals for doppler shift.

I use AGW packet engine software to give me the ability to transmit and receive packet without a TNC and only using my computer soundcard. The UISS software works in tandem with AGW and is a very useful tool for working the ISS or digipeating through it. Within a day of downloading the software (on Saturday 17th March 2006 at 1145UTC), and on my first attempt, I managed to have my 145.990MHz FM packet signal digipeated by the ISS (RS0ISS-3) as it flew overhead at 345km, this was achieved using my normal VHF horizontal beam and using 25w.

See the image below, showing my QTH and those of other successful Hams, displayed in real-time, as heard by the ISS. The ISS position is shown and where it will be in 5 minutes later (ISS-5).

 

                                   

 

 

 



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