Home Data, Audio and Video Cable Requirements
What cable? What hardware?
The design of a multi-room or home cinema system for your property refurbishment or new build starts a lot earlier than purchasing hardware. It should start right at the beginning, with the question, 'what do I want it to do?’. Whilst the answer usually starts off as a basic, 'watch TV in all my rooms', it will most probably evolve in-to, 'I want Sky here, Freesat there, high definition here, music there and just Freeview in here'. All these choices require a slightly different cable infrastructure. The cable infrastructure within your property is one of the most important things to get right, miss something out and you either have to make do without it or have to re-decorate!
Whether you want to use high definition video, Sky or basic TV channels, they all have different signal types and therefore need to be treated differently. We might be able to design a system that uses a single cable to carry these signals, but they will need to be processed differently:
Digital signals
Today many signals are digitally transmitted using a series of 1s (on) and 0s (off) and this gives them an incredible robustness, especially when combined with error checking and processing. This also means that there should be no degradation data transmitted this way will either ‘get through’ or it not, unlike analogue where picture or audio quality may degrade before it stops working. This is why we use digital signals in as many areas as possible; in data, video, audio and TV this is seen as being a good strategy.
Data and voice communications
Data and computer network signals are completely digital, while the majority of telephone and voice services remain analogue The cable used (as probably used in your office) has a unique twist to the cable pairs inside and as well as the cable itself which helps make them very resilient to interference. These cables often reffered to as Cat5/Cat5e/Cat6 can carry both the digital data and analogue voice services in your home, whether you require a sophisticated voice and data solution or just multiple telephone points.
This type of data network will supply the property with a complete computer network and when set up properly it will allow you to share music, files, internet access, emails and even printers with any of the other computers in the property. You can even specify remote access over the internet to be able to access your files and even CCTV cameras while away on business or holiday. While wireless solutions are available, there are a number of issues you need to consider before missing out on the chance to install the correct cables. We can advise you on this using objective testing in your property to establish how crowded the wireless network is in your area.
HD Video
High Definition video signals can be carried in a number of different cable or connector formats which are commonly HDMI, DVI and Component. HDMI and DVI are the same digital video signal type while HDMI also carries audio and Content Protection information (HDCP). Component signals are analogue and technically known as Y, U, and V. Component signals are commonly confused with RGB which also uses the RCA phono connection type with the same coloured connectors; these two signal types are incompatible with each other unless some conversion is introduced.
With HDMI a great deal of care is also needed to handle the complications of devices communicating with each other, as well as compliance to the Content Protection which is a legal feature of the HDMI format. HDMI is a relatively new technology, but by using our experience you can avoid equipment conflicts which otherwise would render your installation useless.
Satellite
The Sky or Freesat satellite signals that come from the dish are carried on industry standard coax cable but they are completely different to those received by a roof top aerial. These signals are transmitted in a digital format and the receiver box is used to decode them for viewing. However in order to increase the number of channels available they are transmitted in one of four different bands and the receiver knows which band your selected channel is in. For anything up to four receivers a feed from the dish direct to each receiver is simple. However more than four receivers or for using a common cable shared with your TV aerial it needs more thinking about and potentially some specialist hardware to separate the bands for distribution.
TV
Basic TV is what we have all been used to for many years; however with the addition of Freeview there are a number of basic considerations we also need to apply. Traditionally TV transmissions were bundled into specific frequency groups per local transmitter, where transmitters overlapped and aerials were installed to match the local frequency group to prevent interference. With the sheer number of Freeview channels and the fact that it needs to share transmission space with the traditional five channels, the majority of the digital channels have been moved 'out of band' meaning that the older grouped aerials are not be able to receive them. In addition, older aerial cables can not reject the increased amount of noise and interference we have around us now and should ideally be upgraded with any installation.
The Crystal Ball
Sometimes the trickiest bit of our job is the crystal ball bit! What is coming, what is going to be a red herring (HD-DVD / Betamax!) and most importantly what cables will you need in 10 years. We have most bases covered with our generic wiring standard for TV, Video and Data as it has evolved from an industry standard scheme and our experience. Even if you only wanted to install a basic coax / Freeview system, we would still provide a system that would allow you to upgrade to HD Video. It not only makes sense to add a couple of spare cables while we are doing the work, but even if you do not use it, what about the next owner of your property?
For data systems we still advocate CAT5e even though CAT6, 7 and even 8 systems are now available. CAT5e is so flexible in terms of what we can feed down it and with billions of miles of it installed throughout the world there is still a lot of development to be seen with this cable and for its cost and flexibility it can not be beaten.
It’ll be all Wireless in a Few Years, I Don’t Need to Install Cables?
Wireless is not the total answer people think it is. The Faradays Cage effect created by foil in plasterboard or metal girders in apartment blocks is one example of a current, but little known issue. Interference is also a growing problem, not only from microwave ovens and lighting systems but also from other wireless networks. With the current frequencies (2.4GHz) available for residential systems, only 13 individual channels are available. As soon as a 14th network comes on line it will have to share a channel with someone else's network, instantly halving the connection speed. Then you have connection speeds within your own network, for every doubling of network devices, you half your connection speed, 1-2-4-8 devices will go down from 54Mbs-27Mbs-13Mbs-7Mbs respectively, which is not going to be much use in the future!
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