What's the difference between analogue, digital, and HDTV
Analogue TV: An analogue television is capable only of displaying standard definition images as currently found on terrestrial, cable, Freeview and satellite broadcasts. Analogue televisions cannot display High-Definition pictures.

Digital TV: A digital television operates using digital rather than analogue signals and broadcasts in true widescreen format. Digital televisions can display HD pictures, though not to their true resolution.

HDTV: A High-Definition television can display analogue, digital and true High-Definition TV signals, although there are a variety of important factors to consider when picking the best television for your needs. The main areas to look at are:

Connections - HD signals can only commonly be transported by HDMI/DVI inputs, component inputs or 15-pin PC connections; so your screen will need one or more of these to receive HD pictures. HDMI stands for High Definition Multimedia Interface. This is a bit of a mouthful. Basically it is a standardised format for the cables and sockets that connect the different pieces of an HDTV system together. It is a replacement for the commonplace SCART connection that is currently in use, as SCART is not capable of handling the high quality HD picture format.

Formats - The two key HD formats are 1080i and 720p. Neither is necessarily better that the other, but your TV needs to be able to handle both for true High-Definition pictures from all sources. For a more in-depth look at this, scroll down to 'Resolutions'.

Getting regular TV and DVD on an HDTV
High-Definition televisions can play regular TV broadcasts as well as HDTV, and will usually make the images better, as most HDTVs feature progressive-scan (an image improvement) technology. This isn't always the case however, as the larger the TV you own (and HDTVs are generally 26 inches or larger), the bigger the flaws in its images become. This is particularly the case with fast-moving programming, like football. One of the main reasons for buying an HDTV, even if you don't have an HDTV tuner or receiver, is DVD. The combination of progressive-scan technology in an HDTV set and progressive-scan compatible DVD player ensures the very best image possible is produced. Watching a DVD in this way means you're getting the best possible picture available, outside of HDTV itself

HDTV Resolutions
All digital displays make their pictures up using pixels, where the more pixels a screen has, the better the image. This is called the screen resolution and it is well worth having a basic knowledge of the resolution formats if you want to make the most informed choice when purchasing your new HD kit.

The two formats for High-Definition are 720p and 1080i. The 1080i format contains 1080 lines of image information, which is produced using the interlaced (hence the 'i') system. This means the pictures on your television are produced in two separate 'sweeps', with the odd lines (1, 3, 5, 7 etc) created during the first sweep and the even lines (2, 4, 6, 8 etc) created during the second. The sweeps are so quick, however, that the human eye sees only one complete image.

The 720p format, while having fewer lines of image information, uses progressive-scan technology (hence the 'p'), where all the lines are created at once, as opposed to two separate sweeps. This ensures an exceptionally smooth image, which is often preferable to 1080i for fast-moving footage (again, such as football).

To give you an idea of what these numbers mean, the standard definition pictures you currently enjoy use only 576-625 lines of information in the interlaced format.

Does Size Matter? 16:9 vs 4:3
Television screens are available in two shapes, regular (4:3 aspect ratio) and widescreen (16:9). Regular pictures are four inches wide to three inches high, while widescreen pictures are 16 inches wide to nine high. Traditionally, films are shot in widescreen format, while TV is shot in regular - hence the black bars that run across the top and bottom of a screen when you watch a film on a regular television.

But as technology improves and with the launch of High-Definition (which is shot in widescreen format), the only real choice is to opt for a widescreen TV when making your next purchase. Almost all large (28-inch and above) screens are now only available in widescreen format though, making it an easy decision to make!

Here is a list of HD channels on the Sky Satellite TV UK system.

Those on a north beam you will have difficulties in receiving on a small dish, and even on a big dish may not be available when the north beam signals are at their weakest - mid to late afternoon.

Eurobird 1 (28.5°E)

ITV HD - free
Rush HD - free
Luxe TV - free

Astra 2D (28.2°E)

BBC HD - free - same frequency as BBC1 Channel Islands

Astra 2A South

Channel 4 HD - needs a FSFS viewing card

MTVNHD
Sky Screen 1 HD
Sky Sports HD 2
Sky Sports HD 1
Sky Real Live HD
Sky Action HD
NatGeo Wild
The History Channel
Biography Channel HD
Crime HD
Eurosport HD
National Geographic UK
Sky One HD
Sky Box Office
Sky Sports HD 3
Sky Box Office



Astra 2A North

Sky Arts 2 HD
Sky Family HD
Sky Movies Premiere HD
FX HD UK
Sky Screen 2 HD
Sky Anytime HD1
Sky Anytime HD2
Sky Modern Greats HD
Sky Drama HD
Sky Scifi/Horror HD
Sky Comedy HD
Discovery HD UK
Sky Box Office
Sky Arts 1
Disney Cinemagic HD U.K.
Sci-Fi HD UK