This page is designed for people new to Amateur Radio or VHF long distance (DX) communications. If you are not already a Radio Amateur, you can watch a RSGB video to show you what our hobby is all about. Please watch the RSGB video click here or read Amateur Radio FAQ.

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.

I will describe below how you can move on from simple line of sight 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 20 years.

50MHz is probably the easiest VHF band to achieve regular long distance (DX) communications, 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 50MHz 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.

144MHz is the mainstay of VHF amateur bands around the World. Most Radio Amateurs will have a radio capable of transmitting on the 145 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. 

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 400 watts and a 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 or Estonia and Iceland via Meteor Scatter from England.

432MHz can be a very frustrating band. Long distance communications are possible via Tropo Ducting, 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 432MHz are much weaker than on 144MHz. 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? 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 70MHz, 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.

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

The Kenwood TS-2000 is good on both HF, 50MHz, 144MHz, 432MHz and can be fitted with 1296MHz too! It has an internal ATU for HF and 50MHz. 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 is unique in that it can also 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.
VHF/UHF Propagation modes explained
Propagation type	Distances	Comments for European stations
Line of sight	0-100km	Dependant upon antenna height above sea level
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. Software calculator here
Tropo Scatter	100-500km
Aircraft Scatter	100-500km
Aurora	250-1100km	Favours Northern Europe. March often good
FAI	250-1100km	May to August, favours Southern Europe
Tropo Ducting	200-1000km	Sea path possible exceptionally up to 3000km. October often the best month. Click here for atmospheric soundings. Select Europe map and then click on site to see readings.
Meteor Scatter	700-2350km	Summer months best for major showers, but winter months active too.
Sporadic E (Es)	50MHz   500-2350km (Single hop) 1000-4700km (Double hop)	50MHz 2,350km is max single hop distance. 50MHz Season is from May to August. Double hop often seen. 144MHz 2,350km is max single hop distance. 144MHz Season is from June to July. Rare double hop possible?
	144MHz 1400-2350km (Single hop) ??? (Double hop)
F2 layer / TEP	50MHz >3200km	Only open 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 2011/12.

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 now use 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 2m 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 2m 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 InternetLinking 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. 

Station A      Station B

  My top tips for WSJT software are:

• If you have an older computer download version 4.9.8 and not the latest version 5.9.5. You must do this if you have a RigExpert interface too.

• Use JT6M mode for 50MHz meteor scatter, tropo scatter and sporadic E qso's.

• Use FSK441A mode for 144MHz meteor scatter qso's.

• Adjust your soundcard received audio level to show 0db on the WSJT screen, for every mode.

• Be patient, meteors can be very elusive outside of showers. Some qso's may take up to an hour!

• Disable your internet browser from playing sounds in web pages, otherwise you are likely to play them over your radio by accident

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).

it's private

		Send formatted VHF DX Cluster spot
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