FreeSat: Introduction

This is a random collection of notes and suggestions in a condensed form for freesat viewers. You can browse this, pick up a few things, and leave the geeky stuff (elsewhere on this site) if it doesn't interest you. I include footnotes for things that may require additional explanation.

 

IMPORTANT: This gets a little 'technical' in parts. Not a lot, but some might find their eyes glazing over.
Tell you what - if you had your freesat receiver installed and you have no wish to stray outside of what the freesat package offers... stop reading.

For those of you still here, I apologise but it is useful to know a few buzzwords like "LNB" and if you plan to tune into any of the hundreds of channels not provided, it is essential to understand the three parts of how to tune in - you can't just tell the receiver to tune to a specific frequency, it's a little more complicated than that.
Again, apologies. I will try to keep it all simple.

 

What I plan to do here

My aim, grandiose as it may seem, is to have this be a sort of one-stop-shop kind of deal for all manner of freesat-related information. As with the Digibox1, some will be my own discoveries, merged with information culled from other resources, and even tidbits people have emailed me; all presented in a chatty and friendly style.
It's early days yet, both for my experience with freesat and indeed for the service itself, however it is unrolling nicely. Obviously the service does not have the commercial backing of umpteen subscribers, so it is likely that it will not reach the scope and sophistication of Sky's offerings, however for God-knows-how-much per month I would not expect but positively demand a good service when I'm paying for it. On the other hand, quirks aside, the freesat service is similar in operation, if different to look at.
That said, it is worth pointing out that the freesat receivers are unrolling with Ethernet2 ports. Whoo!

 

Please NOTE WELL...

This jiggery-pokery is a sort of hobby of mine. This site is a collection of information shared created, essentially, because of a need for a good information resource. Originally there was little on-line about the Sky Digibox, so I asked around, put some pages together. I plan to do the same thing for freesat.
Please PLEASE be well aware that I am not an employee of freesat, nor any of the digital receiver manufacturers. I do not have access to the Goodman's receiver firmware3 (shame!), I am actually employed to work on a production line making little sweet confections.
With that in mind, please do not ask me for support for your satellite receiver and/or equipment. I can provide my suggestions and my opinions, but that is ALL.
 
[might seem obvious, but you'd be amazed how many obscure questions I have received as a result of writing a 'tweaker' program for my (now defunct) Tesco-brand Technika MP3 player; just because I worked out the information in the 'settings' file by trial and error, that doesn't qualify me to tell you what to do if you get odd lines and stuff in the display; for faults the answer is always going to be the same: if under warranty, take it back; else consider getting a new one]

 

Geeks rule OK!

You will see, scattered around, a number of technical things. I will try to write the freesat information more simply than normal as a large number of you are likely to have had your receiver installed for you, so to you it's a plug-n-watch arrangement.
Anyway, here are a few brief examples. You do not need to know this stuff in order to enjoy freesat, it's just here as a crash course.

That's it. It wasn't so painful, was it? That said, if you had your freesat receiver installed, you need to know little of this information.

 

Your dish at a glance

Your dish consists of three parts:
  1. The dish itself
    This is a type of mirror (a "parabola", hence why some refer to them as parabolic dishes) which takes the signals from the satellite and bounces them into the receiving antenna.
    There is little actual difference between a solid dish and a mesh dish. To the satellite signals, both appear the same. A bigger problem is if the dish is bent, even slightly. This could send all the really complicated mathematics right out the window leaving you with naff reception.
    As a rule of thumb, the bigger the dish the better the reception; however in the UK you will be able to get away with a 60cm dish (80cm in the extreme north of England, Scotland, the outer isles, Northern Ireland, and the Channel Islands).
  2. Arm
    This is the metal rod sticking out of the front of your dish.
  3. LNB
    This is the lumpy thing at the end of the arm. Its job is to receive the signals according to the desired polarity, convert the signals to a much lower frequency, then send them along the cable to the receiver. This conversion is necessary because it is physically not possible to send 12GHz down a wire; the frequencies actually used are between about 1GHz and 2GHz. I know, too much information... ☺
    LNBs are typically rated according to their 'noise' factor. The acronym actually means "Low Noise Block", so an LNB with the lowest 'noise' (i.e. interference) will perform the best, at least on paper. These days a budget LNB can manage around 0.5dB and you may find them as low as 0.2dB.
    I say "at least on paper", as tests (in magazines) have shown starting variations in the quality of reception of LNBs across the range of supported frequencies. It may, for example, perform very well in the middle of its supported range of frequencies, and poorly at the extremities?
    I think how much this actually affects you depends an awful lot on your circumstances. I am happily using a £3 LNB purchased from Lidl. I don't remember the rating. I think 0.5dB? Whatever - it is light, reliable, and it works. That's all I ask! ☺

 

The parts of your installation

This is simple. You have a dish (with LNB). This receives the signals. You have a receiver that decodes these signals and displays a picture. And, finally, you have a bit of cable between the two!

 

A few words about cabling

It is absolutely imperative that you NEVER use standard UHF cable. You see, UHF (terrestrial) television signals work in the range of frequences 400MHz to 800MHz (give or take a little); while satellite uses, as mentioned, 1000MHz to 2000MHz. It will work, if your installation suffers damage you can patch it temporarily using UHF cable, however the quality will be seriously degraded and you should not be surprised if a number of channels no longer work. The solution is simple - use proper satellite cable. It is pricier, certainly, but there's a reason it costs more.
 
The cable forms part of an electrical circuit. Your receiver actually sends power to the LNB (13V or 18V depending on polarity, the voltage is used to select). For this reason, there can be no breaks or dodgy connections, and certainly no shorts. If you are making up your own cable, ensure the plugs are hooked in tightly and that the many strands of wire in the outer braid are not touching the solid inner core. Ensure also that that odd waxy-plastic thing around the inner core wire is not obscured.
 
Every join will lose you a part of your signal. The best hook-up is a single fairly short length of cable from dish to receiver. The cable can go up to about 30 metres, but over this length you may find some sort of amplification is required. You are advised to put your receiver and dish closer if at all possible.
 
If you had your receiver professionally installed, we can be reasonably sure that it was done properly, however if a bloke around the corner does it 'on the cheap', the cable is one of the areas of economy.

 

A brief word about dish/LNB matching

In the old days pretty much everybody used a fairly standard shape "offset focus dish"9. This is the traditional style of dish that is an upright oval with the arm sticking out of the bottom. Most domestic LNBs will work with those types of dish.
Then Sky brought out their "minidish" which is wider than it is tall. This necessitates a slightly different design of LNB that is suited for the different dish styling.
While any domestic dish will provide some sort of results with any domestic LNB, please be aware that using a minidish LNB with a traditional dish, or a traditional LNB with a minidish will gave rather sub-optimal results.
To know why, look for a minidish on a nearby house. Think if the LNB is designed to 'see' the surface area of that dish, how well would it work with a traditional dish?

 

A dish on the chimney...

I saw this a lot, but here is as good a place to repeat it. The dish needs line-of-sight to the satellite. That's all. It needs to look up and 'see' it in the sky.
For many years I had my satellite dish resting at ground level, there are photos elsewhere on this site. I latterly moved it to the side of a barn.
Given that it is something like 44,000km (!) to the satellite, placing the dish a few metres higher on a chimney will only make a difference if there are trees and stuff in the way otherwise. Unlike signals received via the TV aerial, a higher-up dish does not necessarily equate to better reception.
So, if you are installing your own dish, you don't need to take your life in your hands clambering around your roof. First, try a solid bit of wall someplace you can get to easily!

 

Footnotes

  1. Digibox - this is a generic name used to refer to Sky's range of receivers. While any digital receiver could be a "Digibox", it is uncommon to use this moniker for anything non-Sky. On this site, Digibox will be a Sky receiver; freesat box (or receiver) will be a freesat receiver; and FTA receiver will be any digital satellite receiver that is not service-specific.
  2. Ethernet - on the back of the freesat boxes (certainly my Goodmans) is a socket that looks like a big American phone plug. It will probably have a little green light that comes on, and a yellow light that doesn't come on. The aim is to, in the future, permit this to be connected to an ADSL (broadband) adaptor to allow viewer interaction. The older Digiboxes do this with a built-in modem (they predate broadband), though obviously they are slower for it. It is, in theory, quite possible for your satellite receiver to provide services such as email access, or linking into a movie information website (IMDb perhaps?) so you can request additional information on movies you see in the EPG. How about after watching Demons, if you could instruct your receiver to go to ITV's website to get behind-the-scenes information on the programme? These services are not available, but in the future they might be...
  3. Firmware - your receiver is actually a type of computer. Computers are all over the place. Got a breadmaker? How about a smart central heating timer? All of these things contain little computers inside, and the 'software' that makes them work is known as "firmware"; because the firm that makes the device puts it there, unlike Windows or AbiWord which you often install yourself.
  4. Astra/EuroBird - four of the satellites that provide your freesat service are Astra 2A, Astra 2B, Astra 2C, and Astra 2D located at 28.2°E. These are run by the SES-Astra consortium.
    The fourth satellite is Eurobird 1 which is a Eutelset-maintained bird (I think), located at 28.5°E.
    The expression 'bird' is a way of referring to a satellite, perhaps most exemplified in the name of the "Hotbird" birds!
  5. sat-finder - a gadget that plugs into your satellite cable and beeps or shows the signal strength on some sort of scale (a swing-needle, lights that get more/brighter, that sort of idea). These are very useful for finding a satellite in the sky as they are a lot more sensitive to incoming signals; however they all suffer from an inability to say if it is the correct satellite. There are many up there!
  6. Rain loss - go outside on a bright sunny day with a thin polyester blouse (if you don't have a handy female, find the thinnest shirt you have). Now put the blouse over your head. That's what the rain is like to the satellite reception. You can (hopefully?) see though the clothing on your head, but it is difficult. For this reason, your dish must be EXACTLY on target. If it isn't, it will work in good weather and fail in the rain. Note that torrential rain and/or heavy thunderclouds can knock out reception, there isn't much you can do about this.
    PS: You can take the blouse off your head now, before the neighbours start to get odd ideas...
  7. 'channels' - Digital broadcasts work by sending a big chunk of data. This data is a series of little packets (think of envelopes in a mailsack), and each of these packets belongs with a specific channel. These channels can be television channels or radio channels (think of addresses on those envelopes). So when your receiver tunes into the frequency you have selected, it receives mailsacks. It looks for envelopes which are addressed to the TV/radio channel you are wishing to receive. From this, your picture and/or sound is created.
    For example, the freesat channels "Chart Show TV", "True Movies", "PopGirl", and others, are all at 11642 V.
  8. European TV - normally means either the older Astra satellites (at 19.2°E) for French/German/Spanish broadcasts, or the Hotbird satellites (at 13°E) for Italian/east European broadcasts.
    I have a secondary LNB pointed to 19.2°E for various French/Spanish channels, but to be honest I usually find myself idly passing time with NHK World.
  9. Offset focus - the dish is designed to reflect the signal downwards, so the LNB can be on an arm sticking out from the bottom of the dish, instead of a round dish with a centrally-mounted LNB. It is simply an economy measure. The larger dishes are circular with a central LNB, and a pricetag to match. Offset dishes are the domestic cheap'n'cheerful version. If you find a special polycarbonate dish with a price running to three digits, go look up the cost of a 1.5 metre circular dish...


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Copyright © 2009 Rick Murray