This post was last updated on September 14th, 2020 at 11:07 am
From the title, you should be able to deduce that this is going to be an intermediate/advanced tutorial on satellite TV installation. However, I have made it so simple so much so that even a beginner can learn. I will still advise a beginner to first read my post on how to track a satellite tv, most popular FTA channels, and beginner’s guide to lyngsat. Today, I will unravel the puzzle surrounding the orbital satellite positioning and the right size of dish to use. In other words, here are hints on how to precalculate the dish size for any satellite package you wish to track/install.
In addition, this post will also contain tips on how to get TP/frequencies and how to interpret some satellite TV terms that are needed for getting the exact size and type of dish needed for your installation.
For example, how do you know that a 60cm dish is big enough to track Dstv Africa channels on Eutelsat 36B at 36ºE(DStv)?
Similarly, How do you know that for you to track Hotbird in some regions, you will need a particular size of the dish?
Basic Satellite Dish components
Before we proceed with how to how to precalculate the dish size, let us get familiar with some basic satellite Dish components. Of course, we can’t get enough of them as they are indispensable to satellite installation.
- Android app that can help you locate where your dish should face
- Hellobox Smart S2: A Bluetooth satellite finder + compass
The Satellite dish/Antenna
A satellite dish is a dish-shaped type of parabolic antenna designed to receive electromagnetic signals from satellites, which transmit data transmissions or broadcasts, such as satellite television. This is one of the most important items to be considered when tracking satellite channels
The LNBF KU Band & C-band
Stands for “Low noise block Feed” converter. Is that part of the dish that sticks out on the arm back to the dish It converts the hi freq sat signal to a lower block frequency pictures below:
The LNB(coaxial) Cable:
This is another item you must get before attempting to track any satellite. The abbreviation LNB stands for Low Noise Block. It is the device on the front of a satellite dish that receives the very low-level microwave signal from the satellite, amplifies it, changes the signals to a lower frequency band, and sends them down the cable to the indoor receiver. Therefore the “LNB CABLE ” is that rope/cable that the LNBf uses in transmitting signals from the satellite dish to the receiver.
The Diseqc Switch
(Digital Satellite Equipment Control), pronounced “Die-Sec”, is a special communication protocol for use between a satellite receiver and a device such as a multi-dish switch or a small dish antenna rotor.
The F connector is a coaxial RF connector commonly used for “over the air” terrestrial television, cable television, and universally for satellite television and cable modems. without this connector, you won’t be able to fasten your LNB(coaxial) cable to your LNBf and your receiver. See the picture below:
Satellite Signal splitter:
We have a 2-ways, 3-ways, 4-ways splitters. the job of this is totally different from that of a DiSEqC switch because it split the signal from one dish among various receivers. It is ideal for houses where we have many decoders and it minimizes how many dishes you install to watch one satellite package picture below:
The heavy-duty actuator /Jack/motor for big Satellite dishes
A linear actuator is an actuator that creates motion in a straight line, in contrast to the circular. Typically though, the term “hydraulic actuator” refers to a device controlled by a hydraulic pump. Air actuators are not necessarily used for heavy-duty machinery and instances where large amounts of weight are present. Since a big dish is typically heavy especially the one made of steel from 2meters and above, you are advised to use a jack. see picture below:
- Satellite Finder/Tracker (Sat-finder)
First off, a satfinder is an electronic device used in finding satellite tv signals and tracking them. some of them even come with a compass that helps you detect the location you are targeting.
Definition of Important Terms With Respect to How To Calculate the Dish Size
The following terms have to do with the non-visible aspect of satellite tv dish installations and configurations.
- According to satsig, dBW refers to the power radiated from the satellite in the direction towards the contour line. Therefore, 45 dBW is the same as 10^(45/10) = 31622-watt transmitter feeding an omnidirectional antenna. dBW is a unit of EIRP
- EIRP: means “equivalent isotropically radiated power” (EIRP) or, alternatively, effective isotropically radiated power. This is the amount of power that a theoretical isotropic antenna would emit to produce the peak power density observed in the direction. More explanation on this later down the line in this post.
- Satellite Frequency: In a layman’s language Frequency, is express in gigahertz. For example, for the C-Band, we can have something like 3.7-gigahertz (GHz) to the 6.4-GHz frequency range. The digital broadcast satellite transmits programming in the Ku frequency range (11.7 GHz to 14.5 GHz )
- A symbol rate, also known as baud rate and modulation rate. It is the number of symbol changes, waveform changes, or signaling events, across the transmission medium per time unit using a digitally modulated signal or a line code. The symbol rate is measured in baud (Bd).
- Polarization; For example, vertical polarisation is when the electric field is vertical. When people talk about polarisation they are referring to the electric field vector. References to ‘vertical’ and ‘horizontal’ are frequent since terrestrial antennas are normally vertical or horizontally relative to the ground. Check out the following illustration: DStv Eutelsat 36e has the following frequency, polarization, and symbol rates; frequency = 12245, polarisation is H, Symbol rates = 27500.
- Satellite degrees briefly explained: If you have something like Eutelsat 36ºE it means your dish will face east and if you have “W” you are facing west.
How to Precalculate the Dish Size Required To Track A Specific Satellite Package in Your Location
It is very likely you have been hearing stuff like you need a particular size of the satellite dish to track a specific satellite package. For example, “track DStv with a 90cm dish”, “track Hotbird 13e with 3meter(300cm dish” and other technical jargon.
You may also wonder why you can’t receive a particular satellite tv package in your region. This and many more will be explained in this section.
Dear readers, we don’t just come about all this measurement and calculations by guessing. There are parameters that you must know, some requirements must be met before you can install a satellite TV in your location.
Factors That Affect The Size of Dish to Be Use for Satellite TV Packages
The first step to receiving a satellite signal in a particular location is the strength of the beam(dBW) and the footprint. Now, even if the footprint extends to your location but the “EIRP” is weak, it means you will need a very big dish to get the signals from that particular satellite.
Analyzing The Concept of EIRP calculation in Satellite TV Installation
Now, the image above just explained EIRP. The simple rule here is: the larger the EIRP value, the smaller the dish that will be required to successfully track channels from that satellite.
Also, from the above diagram, the grey areas stand for the “EIRPS”, the yellow represents the smallest dish you can use to get any channel on that satellite position, and the red background represents the dish sizes that can manage to receive the signal from that satellite. Lastly, the blue column represents the dish size which can get a very good signal.
To simplify this, if you have a satellite dish that covers your area and has a 35dBW, it means the least dish you can use to get any signal from that satellite is a 3meter(300cm) dish while the best dish to use is a 480cm(4-meters) dish.
How to Get the EIRP of A Specific Satellite TV Package
Lyngsat is a very useful website where you can get general information about satellite TV packages across the globe. On lyngsat, you can have access to satellite information such as TPs, eirp, and so on.
A very useful page on lyngsat is the lyngsat-maps.com. You can certainly you can get the map and eirp for any satellite of your choice from this page.
Noteworthy, to get the EIRP of a particular satellite on lyngsat, all you need is the name(e.g MyTV) and orbital position(E.G 16ºEast or West) of such satellite.
Peradventure you don’t know the degree, just make sure you know the satellite name. Next, make sure your search keyword is pointed to www.lyngsat.com.
Trust me, you will certainly get the map, the footprint and the dish size(EIRP) required to get the signal. Now, let me give you a practical example.
For example, to search DStv Africa’s map on lyngsat maps, just type the following into google.com search engine box.
Firstly, input the satellite name followed by www.lyngsat-maps.com. For example, when you search for Eutelsat 36ºE, use the following search terms “EIRP for Eutelsat 36e www.lyngsat-maps.com“. Amazingly, you will be presented with a result similar to the one in the following links and image http://www.lyngsat-maps.com/interactive/Eutelsat-36B-Sub-Sahara-Africa.html as your result.
How to Interpret The EIRP of A Given Satellite TV Package
By way of illustration and for convenience, I have explained the interpretation of EIRPs in a graphical form. Please, study the image below carefully.
Interpretation of the EIRP image
Example 1: DStv Africa Satellite EIRP
The above is a map for Eutelsat 36B at 35.9°E on lyngsat maps. from the get-go, you can see so much information about this satellite package. However, we are only concerned with the followings:
- The highest beam/ EIRP for the Satellite Eutelsat 36B at 36ºE is EIRP 48dBW
- The largest dish required to receive this signal is 190cm to a 240cm dish. However, in Nigeria, we can receive the signal with a 90cm or even a 60cm dish
- Also, the footprint of DStv(36degE) doesn’t extend to North African countries like Egypt and so on. That is to say, even if you have an 800cm(8-meters) dish in Egypt, you may not get a signal from Eutelsat 35.9°E
Example 2: Hotbird EIRP
Similarly, my search for Hotbird which is tagged “the WIDE beam” yielded the following results. http://www.lyngsat-maps.com/interactive/Eutelsat-Hot-Bird-13C-Wide.html
If you want the map and EIRP for I search canaplus SES 4 at 22.0ºW, here you are: http://www.lyngsat-maps.com/footprints/SES-4-West-Africa.html.
From the foregoing, there is no end to the number of the satellite you can search on this wonderful site. Just keep searching and exploring.
This is a very useful tool that will help you predetermine the dish size needed for your preferred satellite package.
Once you are aware of the exact size of the dish that you will need for your favorite satellite tv package, you won’t waste your money on a dish that cannot get the job done. Fortunately, you can’t go wrong when you buy a very big dish. The reverse is the case if you buy a dish that is too small. A small dish can be useless if your target is FTA channels
How to Get other Parameters that are useful for Satellite TV Installation for example frequencies
Next, you may need to get other parameters for your choosen satellite tv packages like the frequency and symbol rate. In this case, you are going to search on www.lyngsat.com and not lyngsat-maps.com.
Apparently, you will still use www.google.com as your search engine. I will recommend the following search phrases: “Eutelsat 36e www.lyngsat.com” or DStv Africa www.lyngsat.com. You need to replace the satellite name in the line above with your preferred satellite. For the examples above, and you will get results similar to the one below.