June & July 2006
As we saw last month there is a lot more to satellite monitoring than just watching television from around the world, and this month we continue our short break from the usual television news to have a good look at DXing Satellite Radio. Have you been noticing the shortwave bands are thinning out? Where are many of the tropical band stations we use to enjoy years ago? Many have moved to delivering their signal to listeners via satellite and FM. This year's WRTH discusses that satellite radio and television is the "new" shortwave. Even the head of VOA has promoted their focus towards satellite delivery.
Satellite radio is basically digital radio that is broadcast by communications satellites. Because the signal is digital, the audio received is "studio quality", sounding just the same as it did in the studio. The majority of satellite radio stations broadcast in stereo. Satellite radio functions anyplace there is line of sight between the antenna and the satellite, given there are no major obstructions, such as tunnels or buildings. Satellite radio listeners can listen to their choice of station in "local perfect quality" across countries or even continents with no static or fading.
Many hundreds of radio stations are available free-to-air on geostationary satellites that can be received in Australia, the majority of these are packaged as secondary audio streams associated with satellite television signals. They require a fixed dish and a satellite television receiver (which is put into "radio" mode) to listen. However many parts of the world feature satellite radio systems that are received by portable radios, in North America many models of cars come standard with satellite radio. In Asia, Africa and Europe portable radios with AM, FM, shortwave and satellite tuners are available. It is this "portable" satellite radio we are discussing this month.
Portable satellite radio is set to revolutionise the delivery of radio programming throughout North America. Both the XM and Sirius networks are finding there is a strong demand for radio delivered across the continent. Europe also looks like it will follow the trend. As we have already mentioned, even Africa and Asia have access to satellite radio services, but alas here in Australia this media revolution looks as if it is destined to just by-pass us. Australia is always notoriously slow to adopt new media delivery technologies. But as usual there is a way for those who are motivated to join in the fun.
WorldSpace Satellite Radio
WorldSpace is a digital satellite radio network based in Washington DC. It covers most of Asia and Europe plus all of Africa with two satellites, AfricaStar and AsiaStar. In the United States, some WorldSpace channels, such as "The System" and "U-Pop" are carried on XM Satellite Radio. Other major content partners include BBC, NPR, CNN, Virgin Radio, Fox News and Bloomberg. Many channels are free of advertising, and WorldSpace has a reputation for delivering high quality programs with "near CD quality" audio
WorldSpace digital satellite radios are produced by a number of electronics manufactures and are widely disturbed throughout Africa, the Middle East and Asia. The consumer's "radio" consists of a satellite receiver plus an antenna that has to be placed in clear view of the relevant satellite. The antenna is oriented to a particular azimuth and elevation which is dependent upon the listeners geographic location. Most of the channels are available only by subscription, but a few services are free to air.
AsiaStar reception in east Australia
During a recent visit to Bangalore India, I stayed in a hotel which featured views through the window towards a gigantic neon sign flashing the words "WorldSpace Satellite Radio". I had previously heard of WorldSpace and had visited their website a few times. The sign encouraged me to make the decision to get hold of a satellite radio receiver and antenna with the help of a local friend. WorldSpace receivers are relatively inexpensive in India ($60 Australian including a 3 month subscription).
For the rest of my journey throughout India and the Middle East I enjoyed listening to WorldSpace from my hotel rooms. All was easy - without problem - you just very roughly aim the antenna at AsiaStar to receive a strong signal. In Chennai the satellite signal was so strong that I didn't even have to point the antenna in any particular direction to obtain a signal. A photo (bottom right) on this page shows the WorldSpace antenna on the end of a pole sticking out of my hotel room in Bangalore. The reason for the pole was to allow the antenna to "see" around the corner of the Hotel building as my window was not facing south towards AsiaStar. The hotel room wardrobe got dismantled for a day to provide the needed rod!
Back in Australia I was aware that not even the AsiaStar southern beam was intended to reach Sydney. The published WorldSpace reception diagrams show the radio signal only just making landfall at the north-western coastline of Australia. This is thousands of kilometers from my home. However I was determined to get a working system at home using the WorldSpace antenna mounted next to a C-Band feed on my 3 meter dish. The idea was to use the large satellite dish as a reflector. The dish would boost whatever weak and feeble WorldSpace signal made it to Sydney. I had some confidence this would be possible, a respected satellite experimenter, Garry Cratt, had successfully received AsiaStar signals some years ago using the same principle.
After a fair amount of reading (including reading of Garry Cratt's experiments which were published in Silicon Chip magazine) I found my BPL Diva brand receiver was "pre-programmed" for the Indian beams. After more reading to understand how the WorldSpace carrier system worked I decided to put all the theory to practice. The result was instant success!
The BPL WorldSpace antenna was removed from its mounting bracket and placed at the focal point of the 3 meter mesh dish, I then drove the dish to 100 degrees East and instantly found AsiaStar. Using the "learn" function of the receiver the system searched and found the carrier beams that made it down to Sydney.
I was very surprised to find that my dish is receiving all three footprints from AsiaStar. The carriers (beams from AsiaStar) being received are:
75 & 80 - India (Western Beam)
43 & 48 - China / Japan / SEA (Northern Beam)
54 & 59 - Indian Ocean (Southern Beam)
All carriers are being well received outside the published footprints with extraordinary strength. The weakest signal comes from the two Indian, carriers, which were initially suffering signal breakup once or twice an hour. Some further adjustments and the Indian carriers were received with a rock solid signal. The northern and southern beams are also being received at good strength and play without interruption.
I have tried to position the WorldSpace antenna to the right of my C-Band LNB in the popular "offset configuration" often used with Ku band feeds. Even after moving the dish a touch to compensate for the offset, I still haven't seen even a squeak of signal. It seems the WorldSpace antenna insists on being placed right at the dish focal point. I'll keep trying - but at worse I will figure out a way to "clip" the WorldSpace antenna to the front of the C-Band feed for when I feel like listening to satellite radio.
After listening to the free-to-air radio for a few minutes and confirming a good signal was being received I went to the WorldSpace website and purchased a one year subscription. The subscription was processed in seconds and now I have all channels open.
Interested in having satellite radio at your place? Well www.worldspace.com has some very good value receiver and subscription starter packages currently available.
To obtain a usable signal strength in Australia the antenna is fitted at the focal point of a satellite dish.
Satdirectory's 3 meter mesh dish is being used to test the reception of Worldspace in Sydney.
Side-car mounting the Worldspace antenna next to the C-Band feed hasn't produced a result - yet!
In Banaglore, India, the antenna is simply crudely pointed south-east to receive a strong signal
WorldSpace antenna used with BPL brand WorldSpace receivers.