Updated for 2007
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| A few years ago, many of us spent a lot of money to install a big satellite dish in our yard in order to get a broader choice of television programming than was locally available at the time. Since then, most have been superseded by the smaller digital DSS dishes and the larger dishes are often sitting idle, no longer used. | Today, there is a new option that allows those of us with a big dish to once again enjoy the "old days" of plentiful free to air (FTA) television. It's known as MPEG-2 and has recently become affordable as well as more user friendly. For example, the receiver pictured above is my favorite and sells for under $150. |
| Increasingly, satellite feeds have switched from analog to digital - mainly because they can send up to 20 times the programming using the same transponder bandwidth as a single channel of analog television. This is possible because digital signals can be compressed meaning they take up much less "room" compared to analog signals. Satellite rental is very expensive and it didn't take long for this new, more efficient method to catch on. One of the methods to compress video is by comparing each video frame to the one just sent and only transmitting the things that have changed. Depending on what's being sent, this can be a huge savings. However, the method has to be able to adjust on the fly in order to accommodate several channels. | Early on, one of the big complaints was "blocking" which occurred when there were more changes happening in the video than the bandwidth allotted could represent. This would appear as small, out of focus squares appearing in the picture where the most movement was. As the technique improved, this problem has been mostly solved. Weak signals will occasionally exhibit this type of interference due to some of the digital data being corrupt. The bottom line to us viewers is that because of the switch to digital transmission, our old analog receivers won't display much of the programming still freely available . |
| Big dishes come in two varieties - C band only and dual C/Ku band systems. Digital MPEG-2 signals are found on both bands and to get the most variety, a dual C/Ku band system is preferred. However, to get started, a single band system will work fine. Since most analog satellite receivers have the dish mover and polarity controls built in, it's usually a good idea to keep the original receiver in the system. What you'll want to do is to install a signal splitter in each coaxial cable between the original receiver and the dish LNB. The splitter must have a LNB power feed through between the input and only one of the two outputs. | Usually you connect your original analog receiver to the powered output and have the MPEG-2 receiver connected to the non-powered splitter output. The LNB on the dish will be connected to the splitter input and be powered by the analog receiver. This way the MPEG-2 receiver "listens in" on the same satellite transponders as the analog receiver. If you have a dual C/Ku band system it gets a little more complicated as you will have two splitters and probably a DISEQ digital switch to allow the MPEG-2 receiver to switch between the C or Ku lines. |
2006 update
| Free To Air (FTA) analog programming has become so scarce it's hardly worth sharing the signal with your old analog receiver. Instead, I use mine to control the dish mover and switch feed horn polarity. This eliminates the need for the splitters and cables to the existing receiver. | For dual C/Ku systems, use the DISEQ switch to select which band the MPEG-2 receiver sees. Single band systems just connect directly to the new receiver. In either case the new MPEG-2 receiver supplies the power to the feed horn. |
| The biggest complaint with early MPEG-2 receivers was how hard it was to find the individual channels. This is because many channels can be on one transponder frequency. To separate them, we must know the symbol rate as well as video and audio PID information. The new generation of MPEG-2 receivers have solved this hassle with a feature called Blind Search. |
Briefly, blind search scans all the transponders on a satellite for MPEG-2 signals and stores the results in an ordered list. Afterwards, you can surf through this list and edit it down to what you like. For the audiophiles there are also oodles of digital radio stations to be found in almost every listening format. The links at the bottom of this page will answer many more of your questions. |
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| For folks who don't have a big dish there's a couple of options. If you have the room, you might consider buying a used big dish and installing it. Often they can be had for little or nothing because the owner just wants to get rid of it. The downside to this is the equipment will probably need some repairs and you may have to install a new feed horn assembly to get the Ku band signals. In short, it can be a lot of work, but will give the greatest selection of free programming and flexibility. |
The second option is a Ku band only system. A basic arrangement like the fixed position dish on the left and receiver starts out at about $250. This setup works best if there's one particular type of programming you're looking for and you're not interested in scanning all the satellites. Otherwise, a toroid design like the one pictured above right can receive multiple satellites in a 40 degree arc. The LNBs are arranged in the feed array to pick up the desired satellites. These LNBs are connected to a selector switch that is controlled by the receiver. No moving parts! |
The third option is a fixed Ku dish like the one discussed in option one with a dish mover attached. For a little over $100 you can add a mover to a fixed position Ku dish and be able to cover the entire visible satellite arc at your location. Many MPEG-2 receivers come equipped with DISEQC 1.2 which is the signaling method used to control the mover through the video coax. Otherwise, a separate box can be purchased to control the dish position. Today, this is by far the most popular configuration because it delivers the most programming variety for the cost. |
Useful Digital Satellite Links
INFORMATION
Satellite Guys - A Great Satellite Site
North American MPEG-2 Information
This page was updated 2-9-08