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The number of options for cabling your home are increasing all the time, with so many technologies and connectivity options available it can be difficult to choose the right option for you. In this section I'll discuss the various options and pros and cons of each.
Broadband
There are several options for broadband internet access now and the best service for you will probably depend on your geographical location. To find the best deal for you I suggest visiting Whirlpool broadband choice.
The broadband option you choose may have an impact on how you want to cable your home, for example if you're going for ADSL then you probably want to have a phone point installed near a power outlet in a central location. You may also want to run Cat5 cabling from the central point to each room in the house. The central point becomes the communications hub for your home, the best location for it may be a study or in the garage.
Remember to run a Cat5 cable to your entertainment system or home theater, if you don't already have broadband enabled devices there you probably will have soon.
Home owners in some new estates now have the option of FTTH (fibre to the home). If you're lucky enough to be one of them you need to give special consideration to the cabling required. In most cases the optic fibre will terminate on an ONT (Optical Network Terminal) that will probably be mounted on the external wall near the electrical switchboard. It may be a difficult job to get additional cabling to this point so if you can get it installed as the house is being built it will be a lot easier. In most cases you will want one coax cable for TV and two Cat5 cables (one for phone and one for internet) between the ONT and the central point.
At the central point you will probably have a router of some sort, in the case of FTTH you will have an Ethernet router otherwise it will probably be ADSL. The function of both being similar, they provide a point of authentication with the network usually via PPP (Point-to-Point Protocol) and may perform NAT (Network Address Translation) so that all the devices in your home can share one public IP address. In some cases the router will also include an integrated VoIP (Voice over IP) gateway, this allows you to connect a standard telephone to the router and make calls via the internet, you will need to subscribe to a VoIP service first and configure the router correctly.
Note a voice service may also be available from the ONT, this may be a different service to the VoIP service from the router, you need to the compare cost and benefits of each option. The service directly from the ONT may be more reliable than VoIP, for example the ONT should have a battery backup in case the power fails, unless you have your own UPS (Uninterruptible Power Supply) the the router will go off if there's a power failure. You should decide how important the phone service is to you and whether you have a backup communications option (mobile) in case of emergencies.
Connecting Devices with Ethernet
Ethernet connections are typically made between a computer and a switch (or hub) in this case the cable required is a standard (straight though) cable (usually blue). If you want to connect one switch to another switch or one computer directly to another computer you need a cross over cable (usually red), these cables have the TX and RX pairs reversed.
Most broadband routers now come with multiple Ethernet interfaces, effectively they include a built in Ethernet switch. You can connect any computer or Ethernet enabled device directly to the router with a standard (straight though) Cat5e cable.
With the advent of Gigabit Ethernet a feature known as Auto-MDIX was introduced, this allows connections between switches or between computers with any cable type (no more need for cross over cables). Most new computers support this now but most broadband routers still do not.
Home Entertainment
Home entertainment options are also becoming more and more complex and there are many different ways to interconnect modern audio visual devices. In this section I'll try to explain the interconnection options and the pros and cons of each.
Entertainment can now come from a growing number of sources, free to air television and HDTV, cable TV and now more and more content is reaching us via the internet. The options for audio are even more complicated several different ways to connect the same devices.
Antenna Connections
A free to air television antenna should be connected using coaxial cable, the cable should be RG6 type and quad shielded if possible. Older antennas may be connected with 300 Ohm flat pair cable, if you have one of these antennas and want to install an additional TV point you will need to connect to the antenna directly with a balun (not stocked) to convert the signal to unbalanced mode compatible with coax cable, this will cause some loss but should be acceptable in good reception areas.
There are two common types of connector used for coax in Australia. The first is the more common PAL type (push in) that has been in use for many years in Australia and Europe. The other type is F-type (screw in) which is a US standard and is more common for pay TV but can also be used for any coax connection. The advantages of the F-type connectors are that they are more secure (screwed in) and the center conductor of the cable is used to connect to the socket. This eliminates the center pin and thus one more possible point of failure, it also minimizes the change in characteristics of the cable which is important for radio frequency signals.
If you want to have more than one TV point then you will need a splitter, as the name suggests the splitter splits the signal into 2, 3, 4 or more for distribution throughout the house. It should be noted that it also splits the signal power for example the output power of a two way splitter will be half that of the input. This should only be a factor if the signal strength from the antenna is low. If that's the case you may need the assistance of a professional installer.
Video connections
There are many different standards for video connections but I will cover only the most common and relevant standards.
HDMI
HDMI is the most recent standard for video signals and is still under development, it is based on the DVI standard (with additional audio channel) and DVI can be converted to HDMI (minus the audio). HDMI supports high definition video with a built in digital audio channel, there is also an Ethernet channel coming in HDMI version 1.4. HDMI is the format of choice if your equipment supports it.
There's a lot of hype surrounding HDMI cables and it can be hard to separate the fact from the spin. Yes it's true that HDMI uses very high data rates and a poor quality cable could cause picture problems especially if the cable is long and there are other components involved (wall plates, switches etc). However as HDMI is a digital signal there should be no degradation in picture quality until the signal quality reaches a point where you notice a significant loss of quality, this is usually seen as "snow" or white speckling on the picture. Anyone who tells you they can see a difference in the picture quality with their $300 1m HDMI cable really has more money than sense.
Though there are several standards for HDMI there are currently only two standards for HDMI cables, standard speed and high speed. High speed cables are certified to handle 1080p signals including those at increased color depths and/or increased refresh rates. Cables that are not specified as certified 1.3a and/or high speed have not passed the required testing and may not support full resolution. Certified cables are generally limited to 10m as longer cables will not pass the testing, this doesn't mean they won't work at all but may only work reliably at lower resolutions/refresh rates (for example 1080i instead of 1080p).
For more information on HDMI visit www.dhmi.org.
Extending HDMI over Cat5e/Cat6
As previously stated certified HDMI cables have a maximum length of about 10m. You can buy longer cables but they are very expensive and still limited to about 20m. A better alternative is to extend HDMI over Category 5e or Category 6 (Cat5e/Cat6) cables. Both HDMI cables and Cat5e/Cat6 cables use twisted pair (two wires twisted together), the twisting is designed to cancel out interference. HDMI over Cat5e/Cat6 extenders simply map the twisted pairs of the HDMI cable to the Cat5e/Cat6 cable, the only difference is that HDMI cable is shielded and Cat5e/Cat6 cable is usually not but this is not normally a problem. There are several types of extenders available some built into wall plates and others stand alone.
Some extenders have no active components at all, they simply connect one wire to another. They are cheaper and work well up to about 20m at 1080i. If you don't intend to extend the signal any further or use higher resolutions and refresh rates then there is no need to pay any more for the active extenders.
The active extenders boost the signal before sending it over the Cat5e/Cat6 cable, they also may include an equalization function to compensate for skew between the pairs, this may be manual (screw adjustment) or automatic. The basic active extenders will extend the range of 1080i/1080p to about 30m with the better ones allowing 1080i to about 50-70m. Be wary claims longer range than this, these ranges can only be achieved at lower resolutions (480i) and can be "optimistic" at best.
We also stock HDMI extender wall plates with built in Infra Red remote extender that allow you to operate the video source from another room.
Component
Component video splits the video information into three separate signals carried on RCA cables (Red, Green and Blue), this reduces the amount of interference between the signals. The three signals are Y Pb Pr
Y carries luma (brightness) and sync information. PB carries the difference between blue and luma. PR carries the difference between red and luma.
There is also another type of composite video known as RGB, though this also uses three RCA cables it is not compatible with YPbPr and requires active electronics to convert the signals.
Composite
Composite video combines all the video information into one signal and is the most common standard used at the moment due to it's simplicity, it uses a single RCA cable (Yellow). The combination of all the video information can lead to some degradation in video quality.
S-video
S-video separates the signal into two components luminance and chrominance (brightness and colour) and uses a round connector with 4 pins.
Audio
HDMI
Yes HDMI is also an audio interface, this means that you only really need one cable between your AV receiver and the TV. There is only one problem with this, at the moment the audio channel is only one way so if you want to get surround sound from your HDTV to the AV receiver you will need to add a digital audio cable like a Toslink cable. There are plans to add a reverse audio channel to the HDMI standard in the future, this should work with existing cables.
Toslink or Optical Audio
Toslink optical audio is a digital audio interface that uses a optic fibre cable to transmit the audio signal using light. As the optical signal is immune to electrical interference there can be no noise introduced into the signal. The optic fibre cables are actually made of plastic (rather that the glass ones use for Telecommunications) so they're relatively cheap also. This should be the preferred method of connecting audio equipment.
Digital Audio
Digital audio uses a single RCA cable (Orange) and is similar to Toslink, this is also an acceptable alternative to optical audio.
Stereo
The humble stereo audio signal uses two RCA coaxial cables (Red and White). |