Digital Television (DTV)
Digital television is a new way of transmitting television signals in a manner similar to how computers store information; digitally.
Digital broadcasting produces a more consistent picture at the same resolution as analogue transmissions, but it does so in a more efficient fashion so its possible to fit several digital channels in to the broadcasting space of one analogue television channel. These two principle advantages benefit both the consumer and the broadcaster; the consumer should get a better quality picture and the broadcaster is able to carry more channels in the same space as before.
Other benefits digital television offers can include:
- Interacive features
- Electronic Programme Guide (EPG)
- Better quality sound
- Access to digital radio stations
Because of the improved quality and the increase in available channels digital offers, most countries have begun the process of 'switching over' from analogue to digital transmissions. Because of the need for all televisions to be upgraded or replaced this process will take some time:
- In the US digital switchover is set for February 2009
- In the UK digital switchover will happen on a regional basis between 2008 and 2012
In order to make this process less painful, most countries and operating a simulcast service with the older analogue systems and the newer digital services running side by side for some time.
Digital television can be delivered via the same methods that analogue broadcasts use, commonly:
- Via an aerial
Although the same broadcasting methods can be reused, new equipment is necessary to receive digital transmissions as existing analogue equipment is incompatible. New television sets can include a digital decoder/receiver built in, however a built-in decoder will not necessarily match your reception method. A more common way to update or add digital functionality to an existing television is to add an external decoder/set-top box which plugs in to the television.
For cable and satellite users, a new digital decoder will be necessary and will likely be provided by your service provider along with any other new equipment needed (such as a new dish in the case of satellite). To receive digital via an aerial you will also need a decoder/set-top box for each television you wish to upgrade, and you may additionally need a new wideband aerial if you do not already have one.
You will be able to obtain more information from your supplier or a retailer as and when necessary.