. twinstaiye:
A BEGINNERS GUIDE TO F.T.A T.V IN THE W/AFRICAN SUB-REGION
(As submitted by Gangsta101)
1. Introduction
Satellite TV has been around for years, as an avenue to watch 24hrs television with diverse programming, and also to listen to crystal clear radio with various content. For years, satellite TV in Africa meant DSTV, that very expensive, but unbelievably entertaining outfit from south Africa. But because most people couldn’t afford their setup, let alone the monthly subscription, people began looking at alternatives, that was what drove the need for F.T.A T.V, which stands for ‘Free-to-Air television’ (though some people might argue that it should be called F.T.V i.e. ‘free to view’, but that’s another discussion). F.T.A has also been around for years, I don’t know enough of the history so I won’t go into it, but the most important thing to note historically is that for years, whenever people talk about F.T.A, it almost invariably meant Arabsat, (well in Nigeria at least). While it was adequate for some purposes, it was very limited, one very annoying problems about arabsat was that it was analog so the pictures were pretty poor and sometimes some channels would cross into each other, and most of the channels were in Arabic, with very little entertainment value for us over here. It became known unofficially as the poor people’s DSTV.
These days however, when one talks of F.T.A, to someone who knows about it, it means a world of unbelievable and almost unlimited opportunities. The advent of what is termed D.V.B (digital video broadcasting) helped spur satellite TV to new heights and F.T.A also tagged along for the ride. While making the content on most satellite tv to be of crystal clear quality and unbelievable diversity, it also makes it possible to broadcast several streams on one ‘feed’, so that one provider can pay for just one frequency on a satellite and then broadcast and several ‘channels’ containing diverse programming, movies, music, news, documentaries, e.t.c., and that is just one frequency, u can have up to 40 frequencies from one particular satellite. However, most of these broadcasts are actually pay-tv, but there are always a few channels which are not encrypted so that one can get these at no cost.
So while a lot of people are into F.T.A because of the cost (or lack of it) a lot more, who may have the money are in it just for the fun of it because apart from tv and radio, DVB also helps broadcast streams for internet traffic and a lot of people are taking advantage of this, but that is gist for another day.
2. Receiving F.T.A broadcast
Receiving satellite streams is a relatively easy thing to do, but it requires the right knowledge, some money, the necessary equipment and a great deal of patience, the first of which we have tried to provide on this forum, but the rest, you just have to acquire yourself. Now there are several things you need before installing a satellite receiver system, and they are as follows:
• The satellite you want to receive.
• The satellite dish
• The LNB
• The decoder
• The wires
• And of course a TV set (or even a computer with a dvb card).
3. The satellite
Which is basically what this whole thing is about. There one basic truth in this fta business, and that is you can only receive broadcast from a satellite whose footprint happens to fall over where you reside. Now the extent to which you can receive the beam depends on how much coverage the satellite has over your area. Basically, broadcasters aim at a particular region. For example, Hitv broadcasts to Nigeria, while Gtv focuses on Ghana, and Nilesat broadcasts to the middle east and north Africa. Now it is impossible for the satellites transmission to be restricted to only a particular country or area, so it goes without saying that viewers in Nigeria will receive Gtv with some slight drop in signal level as you go away from the intended broadcast region. That is what is behind the fact that people in the northern part of Nigeria can receive nilesat’s broadcast with a little less effort than those in the southern part of Nigeria. I do expect that it would be next to impossible for people in south Africa or Jamaica to receive nilesat because of signal attenuation.
So with this in mind, if you want to set up a dish to view fta, you need to check up what satellites broadcast towards the area in which you reside. Luckily for us, the folks at lyngsat.com have taken the pains to map out all available satellites, with their respective channel list and a map that shows expected signal levels and the necessary dish size one needs to catch them. Now because there are lots of satellites whose broadcasts can be received in west Africa, most people tend to try and receive about two or more signals on one dish, this will be touched on later.
Now another information you will get from lyngsat is the azimuth of the satellite in question. This refers to the relationship of the satellites beam to the magnetic north (or in reality, the magnetic south), and this is given in terms of degrees east or west (from the magnetic south pole), for example, nilesat is on 7ºw (that is 7 º in a westerly direction from your south pole), nss7 on 22 ºw, eutelsat w3a on 7 ºE, among others. This is necessary to help you orient a dish. There are also other parameters including the elevation which is relationship of the beam to horizontal on a vertical axis (does that make sense? It sorta means how much the dish needs to be tilted up or down), and finally the skew, this refers to rotation of the lnb around its axis. I could try explaining all of this but I’m not going to do a good enough job without diagrams so I guess I’ll have to refer you guys to dishpointer.com for more information.
4. The satellite dish
Now this is one of those ‘chicken or egg’ situations, does your dish determine what satellites you can receive or does the satellite you want to receive determine what size of dish you get? For places which are within the target area of a satellites beam, the signal levels are pretty high so one only requires very small dishes to get enough signal for watching. But as one moves farther along the footprint of the satellite, the signals attenuate so you would need progressively larger dishes to concentrate enough of the signals to get appreciable levels for decoding them. Let’s use nilesat again as an example, for viewers in north Africa, they would only need a 60 or 90cm dish, in Niger, maybe 1.5m, in northern Nigeria, 1.8 and in the southern part of Nigeria, about 2.5 to 3m. But haven said that, let’s say I don’t want only one satellite but like two or three, say like nss7, w3a and nilesat, because their signal levels are only separated by a few degrees (30 to be exact), one would need a 1.8m dish at least to be able to receive all three.
Dishes come either pre-manufactured or locally constructed, usually the smaller sizes are come as prefrabricated dishes and you only find locally constructed dishes in large sizes. Big does not necessarily mean better, it’s all a matter of what you need to get the job done right.
5. The LNB
This refers to the receiver at the focal point of the dish. The dish concentrates the signals towards it’s focal point and the lnb receives this signal and converts it into electrical waves for the decoder. Now satellite TV is broadcasted in 2 basic bandwidths, the c-band and the ku-band. So there are two basic types of lnb to receive these two types of signals. Most satellites broadcast either one of the two types, though some like nss7 broadcasts in both bandwidths, you can only receive one bandwidth with a given lnb though. So the thing to note about lnbs is that you need a good one to get far off signals. Also depending on the satellite you want to receive you have to rotate the lnb properly to get the right signal. This is the skew I mentioned earlier.
I also made a hint about receiving two or more satellites on a single dish, this is the multi-LNB set up. This is done for satellites whose beams are close to each other, by placing the lnb at a given angle on the dish, you might be able to receive signals from a satellite you are not directly facing. These signals are combined together and passed on to your decoder via what is known as a diseqc switch. (This allows for rapid switching between lnbs). Note, you can also combine c and ku band lnbs via a diseqc. There are various types of both lnbs in the market, ranging from as low as N400 to as much as N3,000. it is my esperience that the more expensive lnbs usually have a better signal amplification, this does not mean you need to go and buy bery expensive lnbs for all satellites. The relatively cheaper ones are okay for signals broadcasted to this region like eutelsat w3 and 4. but for signals coming from a distance such as nilesat you would need a very good lnb to ensure good reception.
6. The Decoder
This is what converts the electrical signals from the lnb into what the TV can use. Now since this discussion is about fta, we have to focus on decoders that can be used for that purpose. Decoders gotten from pay TV companies have been configured for use for receiving their transmissions, what we need for fta is a deocer that can show you what satellite signals are available in your area, allowing you to chose what you want to receive, while also allowing you the option of using it for pay TV. There are several types of decoders that fit this bill, and the most common manufacturers are strong, humax, technomate, kaon, etc.
More recently, computer users have been provided with what is known as a DVB-S card which can be incorporated into the computer so it can be used as a decoder among other things and it can serve the same purpose ad a stand alone decoder.
NOTE: a brief note about the type of wires used for setting up satellite TV connection is in order. Ordinary wires cause the signal levels to drop along the length of the wire so that if the distance between your lnb and decoder is far, all the signals from your lnb might have been lost before it gets to your decoder. For this reason, a special type of coaxial cable which has an insulation sheet between the inner and outer wires, which has a reflective surface facing inwards to help minimize signal loss is used. Even then, at distances greater than 50m the signal attenuation becomes significant enough to mess up your signal, so you might need a line amplifier.
7. Setting up a typical system
Now assuming you have everything you need, let me talk you through the steps necessary to set up a typical system. For this illustration, let us use nss7 ku band, which is a fairly ubiquitous satellite. Now because I am based in northern Nigeria, I know I don’t need a really big dish so I will opt for a 90cm dish as this should give me enough signal concentration for all practical purposes. So the first thing to do is to chose a part of the exterior of my house which should give me a clear line of site to the satellite. This invariably means the north-eastern aspect of the house. Next I have to ensure there are no trees or other obstacles blocking my line of site.
Now another consideration is whether I am going to do a wall mount or a ground mount. For small dishes like 60 and 90cm, a wall mounted unit is usually the best though it requires more technical know how to accomplish attachment to the wall. With larger dishes such as 1.5 and above, mounting it on the ground remains your surest bet, as this gives you etter options for securing it properly from the wind which is the greatest danger to satellite dishes. Personally, for my setup I would prefer to use a ground mount via a pole, this will allow me to be able to rotate the dish towards the east if I get tired of my present satellite, it is also very good for motorized units. What this entails is driving a pole, (a good stout metal one) into the ground and securing it with concrete. Then it is to this pole I will attach the dish.
Now it’s time to do the actual tracking. This is done outside the house. Use a long extension cable to bring a power point outside and attach your TV and decoder to it and power up. Next, attach the lnb to the dish at the focal point and connected it via a cable to the decoder. Assuming I am using a strong decoder, I will then try tracking the satellite from here. To do this, press the menu button, this will bring up the system menu, shift right under Installation to the fifth option which is ‘m anual scan’. Pressing this will bring up a list of satellites. Scroll laterally to nss7 ku, there is already a list of most of the available frequencies from that particular satellite. The first frequency listed is 10.756, with V polarity and a symbol rate of 27500, written in short hand as 10756v27500. then back to the dish, use the a compass to calculate 22ºw from south, twist your lnb so the point the wire attaches points about 45 º to your right along a vertical axis. Then move the dish up and down slowly and turning it right or left until the two red signal indicators for level and quality turn green. Then try adjusting it by small degrees in all directions until you get the maximum signal levels attainable. Try and aim for a signal level of at least 80% to ensure that every available frequency from that beam will be at their maximum. The frequency used for tracking any satellite is usually that which has the highest signal levels and thus is the easiest to pick up. By adjusting it to the best level you can, you ensure that those frequencies which have a lesser intensity will also be at their peak.
After this go back up one level and you will see the option for blind scan, press this and wait, it will scan for all available transponder frequencies from that particular satellite including those not included in the decoder but are being broadcasted. After this, save and exit. You will see a lot of channels, the ones with the dollar symbols are the encrypted ones, while those without are the fta channels.
Let’s say I wanted to get more than one satellite, I would have used a 1.5 or 1.8m dish as this would give the necessary dish diameter for receiving satellites that are not too far apart. Let’s say I wanted to receive nilesat, and nss7 ku, I would first start by trying to track the nilesat, since it is more distant, it would require the maximum dish diameter possible. So, the steps listed above, but somewhere between the lnb and tne decoder, as close to the dish as possible, put a diseqc switch, then use the same tracking procedure, but you only attach the diseqc after you have finish setting up the lnbs and they are receiving signals. For nilesat, the frequency with the highest signal level is 10.756V27500, so by setting the manual scan frequency on nilesat to that, then use your compass to estimate 7ºw, the lnb skew is similar to that for nss7, then tilt the dish slowly up and down and move it slowly right or left until you can get the maximum frequency possible. Please not that unless the signal level for that particular frequency is at least 75%, you cannot get the other frequencies clearly, so with this in mind, try tweaking with the dish until you can get at least that, then do a blind scan for nilesat.
Next, to track nss7 ku, apart form a new lnb, you would need a connecting rod, this is usually available at all stores that sell things for satellite TV. This provides an extension to the dish, to which you can attach a new lnb. Remove the wire attached to the nilesat lnb and attach it to the one for nss7. Now, because the signals for nss 7 are coming from the right if your back is to dish receiving nilesat, it means they would reflect from the dish left hand side of the dish. Also, the beam is coming from a slightly lower angle than that from nilesat, so it would be reflect to a slightly higher level. So with this in mind, your lnb will be placed slightly towards the southerly part of the dish (i.e to the right hand side of the nilesat lnb if you stand facing the dish). To receive this signal move the lnb slightly outwards in short steps while moving it slowly up and down until you hit the signal, then keep tweaking it until you get the maximum signal level possible.
Next connect the diseqc by attaching short wires from each of the lnbs to the diseqc inputs 1 and 2. then the main cable going to the decoder is attached to the diseqc and it is hidden somewhere at the back of your dish. Next take the decoder to the menu page and under dish setting find nilesat, and set the diseqc switch mode to ‘on’ and below that, select, the diseqc input number for nilesat, the nilesat signal bars should turn green. Do the same for nss7 and you are good to go.
Moderator's Comments
Please if this write up assist you greatly, pay for it by doing a token of 'thank you' to Gangsta101 on FTA Forum i.e https://www.nairaland.com/nigeria/topic-7715.0.html |
