The satellite. Unfortunately, I'm hopeless at maths and these link budget calculations always leave me scratching my head. But you should be able to find several web site calculators that will do the hard part for you.
Alternatively, simply try it and measure the signal that reaches the receiver. If it's too low, use a larger dish. The choice of cable and LNB will usually make very little difference to the signal level.
Why is your cable more expensive than ...?
The most expensive component in coaxial cable is the copper. Manufacturers might make fractional savings on plastic and manufacturing costs but they all pay the same price for copper. Our profit margin is tiny so, if you find cheaper cable, it probably contains less copper. That means higher resistance and consequently higher signal losses.
Cable length is important
Even the best cable loses a lot of signal so arrange it so the cable run is as short as possible. Don't leave a coil behind the TV "just in case". Every additional metre will make your "rain margin" worse!
I want to join/extend my dish/aerial cable
OK, read this page.
Don't use an amplifier
There are certain situations where an LNB amplifier might be required. Usually it won't help. For terrestrial TV, a masthead amplifier is sometimes required. Where signals must be split or boosted, an amplified splitter or a distribution amplifier may do the job.
Use a larger dish
To combat loss of signal due to cable length or trees, use a larger dish. We can supply a "zone 2 minidish" which is a little wider than a standard minidish but has 50% greater area. We can also supply a 60cm "perforated" circular (almost) dish for even more signal. We also offer an upgrade kit if you are unsure about what to buy for Freesat/SkyHD.
Use a better terrestrial aerial
In 85% of the UK, a log-periodic aerial is by far the best choice and the most likely to be successful. In only 15% of cases will a high-gain Yagi do a better job!
Contents
Connectors
Extension cables
Cable notes
Wall sockets
Cable types
Cable length
Which cable?
Tips for installing
Cable weight
Best cable
Questions
 | F connectors - You can order these separately and fit them yourself or we can fit them to cut lengths of cable for you (at a small cost). We fit only the screw-on type to our custom-made lengths. You can easily unscrew the F plug to fit a weatherproofing rubber boot if required. PLEASE be sure to order the correct plug to match the cable. See notes HERE. |
 | TV (IEC or Belling-Lee) plugs - we can fit these for you to WF100 - and we supply a link where you can download instructions. |
| | Click HERE for more information about plugs if you are not certain what you have or need. |
We supply Extension cables (catalogue page 8) but read these notes:
You can select colour, type length and add accessories if required (for each individual cable).
Note: if you order a rubber boot with a pre-made cable the boot will be supplied separately. If you need to pass the lead through a hole (or fit a rubber boot) you can simply unscrew one "F" plug then screw it back on afterwards.
Digital signals and analogue signals which now go as high as 2 GigaHertz in frequency need a high-quality double-screened cable, as everyone knows. However, some people don't realise that the cable should preferably be a continuous length without any kinks or connectors. This applies as much to Terrestrial signals (such as "Freeview" in the UK) as it does to satellite signals. The reason is that any "discontinuity" in the cable can reflect the signal backwards which causes a cancellation of the signal, resulting in a poor "Quality" reading in the menu, picture freeze, missing bouquets and a whole range of symptoms that you probably attribute to the weather! You can even lose all picture and sound completely.
YOU SHOULD NOT use ordinary brown or white "low-loss" TV coax if you want to ensure good results! Ordinary "low-loss" TV coax has only 60% shielding (no foil) and is specified to work up to only 1GHz (not 2GHz as required for satellite LNB signals). Obviously there's no harm in trying it if it's already fitted, but don't be surprised if the result is "pictures breaking up" or "some channels missing". (You may find that standard 'F' connectors do not fit on TV aerial cable. Also the centre core may be too thick and might damage the female connector).
Many installations have already been done with wall plates. Indeed, many more will be done because it is unavoidable or because "it looks nicer" or is "more convenient". If you must use a wall plate, then the accessories below will help to avoid problems. We stock fully-shielded wall plates in ready-made and in modular form (select your desired sockets to fit into the plate bezel).
 | To join cables use our 090-3078 threaded "F" barrel and two "F" connectors. We also stock a good quality wall plate with an "F" barrel fitted. |
 | Or you can buy our blank wall plates and fit your own. You can use metal or plastic wall plates. See our "Shop" for all these items. |
 | Note: Although we stock LNB amplifiers, these will not compensate for a bad connection! They are intended for use where the LNB cable length exceeds 45 metres. Wherever possible, you should use a larger dish instead. |
Note: where it is necessary to combine signals into one cable (as with a "Loft Box" or "Diplexer") then use of a decombining plate is unavoidable. We stock only the highest quality fully-shielded wall plates.
SATDS (RG6) is low cost, very flexible and ideal for making short connecting leads and for runs around the house. The main drawback is that it's more easily crushed and kinked. Also, because of its aluminium and copper shield, it's very susceptible to damage in damp conditions and it's more "lossy" than other cable which uses only copper so using it for long runs (more than 30 metres) or outdoors is not recommended.
CT100* and H109F*/WC100 are slightly more robust but still susceptible to kinking. Losses are lower than SATDS and they survive outdoors better.
*CT100 supplies have disappeared since the manufacturer "Raydex" was taken over. H109F is also obsolete. We offer WC100 which is identical.
WF100 has a foam plastic dielectric which makes it less susceptible to kinking. It is slightly less flexible than air-spaced dielectric but, used indoors where it's warm, it still has adequate flexibility. Used outdoors, it is less susceptible to water ingress.
There is virtually no difference in electrical performance between WF100, H109/WC100 and CT100 but WF100 has a foam dielectric, which makes it more robust and harder to kink. It's ideal for use almost anywhere and is available in various colours but it costs a little more. It is available as single or "twin" (two cables moulded together for convenience). It's available in SIX DIFFERENT COLOURS!
( HD100 - we do not stock this cable as I can see no significant advantage over WF100.)
WF65 replaces CT63 "shotgun" cable. It is a twin cable which is very narrow diameter and can be pushed through a 10mm hole. It requires a special "F" connector. It's fine for RF connections but not recommended for LNB runs of more than 20 metres because it loses more signal than thicker cables. This can reduce your "rain margin". In other words, you may lose the signal in bad weather. (If this happens you could compensate by installing the next size larger dish). For longer runs we can supply WF100 in "twin" format.
IMPORTANT: The copper core (centre wire) of WF65 is thinner than that of other cable. If you connect it to an LNB or tuner that has for years been home to a thicker coax core wire it may not make a reliable connection! You may need to double it over and/or solder it to make it thicker.
WF125 cable is thicker, stiffer, and has lower losses than the cables above. Recommended for long LNB connections (e.g. over 40 metres) or where signal loss must be minimised. Note, however, that WF125 is stiff and should not be connected directly to indoor equipment as it can put excessive strain on the connector. We recommend that you use a threaded coupler and a short length of more flexible cable for this connection. We supply twist-on "F" connectors for this cable. (You can not fit a rubber boot to a WF125 connector so use self-amalgamating tape).
WF125 can be connected directly to the LNB but the same comments about additional weight and stiffness apply. It can put extra strain on the connector and the extra weight can cause the LNB support arm to bend.
For long cable runs an equalised slope amplifier may be needed to combat cable attenuation (which is greater at higher frequencies - hence the need for an "equalised slope amplifier", which amplifies higher frequencies more than lower ones).
However, since an amplifier also adds electrical noise to the signal, it is invariably better to use a slightly larger dish than to use an amplifier.
LNB sliding cover
LNB sliding plastic drip covers don't fully protect the connections from rain or condensation so you must use silicone grease on the LNB connections. But drip covers do help to prevent deterioration of rubber caused by ultraviolet radiation from the sun. Without a sliding cover, use self-amalgamating tape (or rubber boots if you are not using WF125 cable).
What's the best cable? Read the review
Please note that SATDS, WF125 and CT63/WF65 are not included in the review.
How long can a cable be before loss of picture quality occurs?
This comes under the category of "how long is a piece of string". Basically, there's no answer unless you know the input signal level and the minimum output signal level required. You can then work it out by looking at the loss per metre. For our WC100/WF100 cables, the loss is about 13dB/100m at 470MHz (typical UHF) and around 27dB/100m at 1750MHz (typical satellite LNB frequency). SATDS is fractionally worse. and WF65 is a lot worse. So, if your UHF signal is only just high enough and you decide to add, say, another 46 metres of cable, you'll need a 6dB amplifier to compensate for cable losses.
Which cable?
| 
| WC100 with air-spaced clear plastic dielectric |
| WF100 with foam white plastic dielectric |
For the outdoor connection, BskyB recommend a *minimum* specification of "CT100/H109F/WC100". This has lower losses than, say, "SATDS/RG6" and uses double (copper-on-copper) shielding. "WC100" has an air-spaced plastic dielectric which is fine but it kinks more easily than foam dielectric and also, if water gets into the cable, it can run down the air spaces and into the equipment! "WF100" is better as it uses a foam dielectric and is less prone to moisture ingress and it is less easily kinked. However, it costs slightly more. Cable such as "SATDS/RG6" is OK for indoor use but can suffer from corrosion outside because it uses aluminium-on-copper shielding. As the PVC sheath ages and cracks in the presence of wind, rain and UV radiation from the sun, moisture will get into the cable and corrosion will accelerate, forming hard lumps inside which crush the inner air-spaced insulator. At such points, "discontinuities" occur which will block or reflect the digital signals, causing serious affects to the picture and sound on certain channels. You can use any of our cables outdoors, provided that you protect it from sunlight and rodents. Best to clip it high on a wall, in maximum shade, and paint it with an oil-based paint to protect it from the effects of ultraviolet and rain. If it has to go underground you MUST put it in water-free trunking to protect it from rodents and small animals, who will chew it, and from water and soil microbes. You can use any of our cables indoors.
Tips for installing cable:
Use the correct 'F' plugs and fill them with silicone grease outdoors
We don't recommend using "standard low-loss aerial coax used for receiving television transmissions" as it is only single-screened. This "TV aerial coax" has only 60% shielding (at best) from external interference. Digital "Freeview" transmissions are very susceptible to "impulse" interference from light switches, street lighting of the gas-discharge variety, thermostatic switches (eg, central heating boilers), vehicle ignition (main road traffic), and generally from 230v mains wiring. The terrestrial aerial must be kept away from the road and the cable must be kept away from other wiring. It should preferably have no joints and definitely no unscreened connections. Sky Digital can suffer from interference from DECT phones and police-radar defeaters as used illegally in some vehicles.
For coaxial connections between the Digibox and other equipment you should still use double-screened cable. This will give the lowest signal loss, the lowest interference pick-up and it's specified for Digital Terrestrial and for "SkyLink" systems such as our "Digilink" and "SLXlink" (and the Global "tvLINK") as well as LNB/DISH feeds.
Weight of cable
Copper-on-copper 7mm coax weighs 47.7g/m (4.77kg/100m)
Copper-on-aluminium 7mm coax weighs 42.5g/m (4.25kg/100m)
An empty cardboard 100m reel weighs (typically) 200g.
250m reels are normally made from wood and weigh a lot more.
See our COAXIAL CABLE SPECIFICATIONS page.
What's the best cable? Read the review
If you are suffering from interference on TV pictures, please click on this link.
We do not currently stock CT167 or any cable with a core diameter of more than 1.25mm because this type of cable is generally not necessary for DIY and because it requires special connectors. You can't simply twist on an "F" connector. It needs the correct crimp connector and the correct tool to crimp it. This cable is very expensive and is used mostly for SMATV systems and transmission stations.
co-axil cable co-axial cable
Our Cable page is HERE
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