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Reception of weather satellites

Broadcast-DX is the oldest form of DXing second to telegraphy transmissions. The majority of our listeners undoubtedly know that the term DX stands for 'distance' or long distance. It means listening to radio stations over a long distance. This happens mostly on shortwave since this is the frequency range most suitable to bridge long distances.

Not all radio hobbyists call themselves DXers. People who listen to large international stations like BBC World Service, Voice of America or even our own Radio Vlaanderen Internationaal fit into the category of 'shortwave listeners'. It's a very interesting part of the hobby, which often brings knowledge of news items never mentioned on the local stations or even the news giants like CNN or BBC world. Shortwave always guaranties the 'free flow of information'.
DXers on the other hand make it a sport to hunt for small or weak stations in the most remote parts of the planet. These are mostly broadcasts not even meant to be received in our parts of the world. They are usually local programs from faraway places which, through a fluke of the laws of nature, get lost and arrive at our aerials. The reception quality is considered a challenge rather than an obstacle. These programs from such exotic places are more often than not in a totally strange and unintelligible language for us. This adds a language barrier to the challenge. In spite of all these factors it's usually possible to identify the transmitting station. Often a good contact with other hobbyists is crucial for this process and this is where the internet has become an important tool.

A serious hobbyist will use very sophisticated equipment in order to get good results, and aerials get their share of attention. Interfering stations can often be suppressed by experimenting with directional aerials.
And for those of you that thought that enough is enough and that our passion carried us far enough it may be interesting to know that the 'hard core' of DX-Antwerp goes for field days at least once a year. The entire 'Radio Shack' is emptied and transferred to the woods in the electro-smog free area near Kasterlee (Belgium) where we rent a bungalow. There we also have space for the some hundreds of meters long beverage aerials. It's here that we test new concepts for aerials like the K9AY. The result is always a nicely filled logbook in our DXA-bulletin.

Since the beginning of radio it has been a custom to ask for reception reports in order to determine the quality of reception in a target area. As a sign of appreciation a so-called QSL-card would be send back. These were usually beautiful cards on which the station confirmed the particular reception. This practise is still followed by the majority of the stations, even though with today's very advanced techniques such a remotely operated receivers, reports are less vital as they used to be.

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A few decades ago, utility DX was limited to the reception of CW telegraphy, as well as listening to maritime or aeronautical communications or so-called point-to-point stations. These last ones however, mainly used for intercontinental phone lines, have almost all disappeared to be replaced by satellite links. Listening to ships, aircraft and Morse stations is still a fascinating thing for the utility listener. Quite often you need to be well acquainted with the typical jargon used in this sort of radio traffic. In the mean time, a whole new array of possibilities and modes appeared in the world of utility. Already in the seventies you could get a facsimile weather map or newscasts from press agencies in Radio Teletype modes, but it was often very difficult to get the bulky equipment (which was sometimes to be found in ex-army dumps) working. On top of that, they were so noisy in operating that you didn't make yourself very sympathetic with the people you shared your house with.

In the beginning of the eighties, things dramatically changed with the appearance of the Tono 350. This blue miracle managed to put Morse and RTTY signals on your monitor screen without any noise whatsoever. A new world opened, and this new form of DXing got very attractive. New possibilities for the reception of fax-weather maps became available, and a whole generation of easy-to-built diagrams were published in various magazines. After careful study of a working model, ten fax decoders were built in group at the club. A few of these have survived till today!

But the evolution went on. Utility services developed always better systems of data transmission with internal fault correction to counter the unreliability of shortwave propagation The serious hobbyist followed the new developments closely. The personal computer got a fixed place in the radio corner, and hobby software started to appear. Those who didn't want to spend fortunes on buying computer programmes wrote their own software.
We have those kind of people as well at DXA!

Even if the utility DXer is known for surrounding himself with lots of knobs and flashing lights, recently it's back to basics. A few years ago it was said worldwide that all stations transmitting in CW Morse would be halting their activities as from January 2000. Lots didn't, but the attention was drawn once again on this form of utility, and the hunt for them is open! Radio beacons, often with very low power, form a target for a few specialists in DXA.

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Lots of FM DXers will surely recognize this: you're an enthusiastic SW or MW DXer and you're intrigued by the logs of distant FM stations in your favourite DX magazines. How can this be possible? Can you really receive Spanish stations in Western or Central Europe, or Scandinavia and vice versa?
Moreover these stations are received in stereo and with RDS, even on your car radio. It's very fascinating and before you know it you've bought your very first FM aerial and connected it to a portable receiver or to an old tuner and then the fun begins.

After reading some articles on FM DX you know distant FM reception is possible through tropo (temperature inversion), Sporadic E (reflections from ionised layers), and even meteor scatter, (reflections from the trials meteors leave behind for a few seconds). Soon stations from over 2000 km away are heard. It's not uncommon to hear FM stations from Spain, Morocco, Finland and many other countries here in Western Europe.

What do you need to start dxing the FM band? Of course a good directional aerial, preferably with 5 or more elements, is needed. It will help you identify stations on the same frequency but coming from different directions. The tuner can be an ordinary commercial one. You can use better IF filters to improve the selectivity.
Nowadays most tuners come with a RDS readout and that's of course a big aid in identifying the station you're listening to.
With some minor modifications to the tuner and RDS decoder and by using appropriate computer software, even more RDS data can be extracted from the incoming signals.

Should you really go on a buying spree and get some brand new equipment? Of course not. Lots of distant FM stations have been received on car radios and on portable receivers only using a whip antenna.

The next job is to familiarise yourself with your local FM Stations on the band. When you know your local FM dial perfectly you'll be able to tell straight away as soon as something extraordinary is going on.
Of course you should keep an eye on your local weather and the weather maps. Also keep in touch with other FM DXers in your area. This will help you to predict good reception conditions and with the help of your friends not many DX openings will be missed.

What's the fun of DXing the FM band? Ask this any SW or MW DXers and you'll surly get the same answer. It's a thrill hearing stations you shouldn't be able to hear. It's pure magic when suddenly that distant station appears. Unexpectedly your computer starts decoding RDS data from a station located at some distant holiday resort. What more can you want: a nice evening, a cool drink and a distant station booming in?

If you're looking for some great DX, interesting chats with other FM enthusiasts, lots of fun building and testing new aerials, tweaking RDS software, then go for this small but fantastic branch of the DX tree.

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Reception of weather satellites
Man has been fascinated by the phenomenon weather since earliest times and the launching of weather satellites announced a revolution in weather prediction. Ever since it has been possible to monitor quite accurately the development of weather patterns without the need for an extensive network of observers. The reception of fax signals, with regular broadcasts of satellite pictures was also for the shortwave listener a revelation.

The quality of these fax images were unfortunately incomparable to the images received by national weather stations all over the world and the price tag for the necessary equipment ran into several tens of thousands of Euros. An experienced and enthusiastic amateur will not be put off by this, and constantly searches for solutions and new challenges. The first attempts to receive weather satellites were made some decennia ago. It had already been possible to hear the signal on the 2-meter band but software to decode this was still to be developed. 20 years later any motivated, enthusiastic radio amateur can receive the signals of weather satellites.

Just what can be heard, or rather seen? We need to make a distinction between two kinds of satellites. The polar satellites circle the earth at a height of approximately 800 km and pass us daily. The geo-stationary satellites are located at a fixed point above earth at a height of some 36.000 km. This explains their much broader view; at this height the earth can be viewed from a certain angle. Both types of satellites have 2 transmitters on board: one digital, the other analogue. Digital information supplies a much higher resolution. Analogue reception is possible with an omni directional antenna and a broadband receiver on 137 Mega Hertz. Digital reception on the other hand happens at a frequency of about 2 Giga Hertz. A dish aerial is needed for this equipped a tracking system if you want to go for polar satellites. This means they have to be able to follow the artificial moon in its orbit around the earth.

Buying satellite reception equipment is becoming more feasible for the amateur listener. Another possibility is to build your own equipment, at a fraction of the cost. A host of fellow hobbyists worldwide will supply you with enough info to get going. No wonder that several of the members of DXA have ventured into the world of weather satellite reception with some amazing results.

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