What is Digital TV and Do I Need a New TV Antenna Installation?
24 June 2018
So What Is Digital TV Anyway?
Prior to Digital TV, there was Analogue TV. Analogue TV transmissions make use of analogue signals to transmit video and audio. Analogue signals are processed using rapid variations of the radio-frequency wave attributes to indicate the colours, brightness and sound. An example of these attributes are the amplitude, frequency and phase.
Digital TV uses digital encoding, which uses RF waves to represent data as a sequence of discrete values (rather than continuous values). Because of the way this information is transmitted, digital TV makes for a much more efficient use of the highly valuable radio-frequency spectrum. It also possesses the ability to transfer other information or new features that analogue TV cannot. Perhaps most importantly, it can even transmit multiple channels on the same bandwidth!
Are There Any Downsides To Digital TV?
When completing an analogue TV antenna installation, there were numerous potential issues in getting a guaranteed clear picture and audio on your TV. The most common reception issues with analogue TV are:
- Ghosting: getting more than one identical image replicating on your screen, which makes it look like there is a ghost. This is actually caused by your antenna receiving multiple analogue TV signals at the same time.
- Snow: your images may look like it is snowing, with black and white pixels overlayed on the image. This is most likely a result of ‘noise’ in the signal that is being received by your TV.
Because Digital TV transmits as simply a ‘0’ or a ‘1’, you will either have reception, or you will not have reception. With the exception of pixilation (which is bordering on failing signal), it is a binary outcome. On one hand, you will not experience ghosting, snowy images, or any other analogue issues, but at a certain point, you will not receive reception at all. This is what we call the ‘digital cliff’, where the signal literally drops off a cliff at a certain point, when it goes from ‘On’ to ‘Off’. The image below shows the most common Digital TV reception issue, pixelation.
Timeline of Australia’s Switchover to Digital TV Transmission
Australia has now turned off the transmission of all analogue TV, and the table below outlines a short timeline of the history of digital TV in Australia.
|1950s||The first TV transmissions in Australia.|
|1 March 1975||Colour TV is launched in Australia.|
|1 January 2001||Digital TV launches in Sydney, Melbourne, Brisbane, Adelaide and Perth.|
|1 August 2001||The First Digital Only TV Channel, ABC Kids, is launched.|
|18 December 2007||The Australian Government announces switch-off of analogue TV will take place between 2010 and 2013|
|24 November 2008||Freeview Australia is launched.|
|26 March 2009||One HD launches – the first commercial digital-only network in Australia.|
|2013||Staged throughout 2013, analogue TV is turned off across different regions of Australia. The future is now digital only!|
For more information about Australia’s switchover to Digital TV, visit the ACMA website here.
My TV Still Works After The Digital TV Switchover. Do I Need A New TV Antenna Installation?
Whilst it is possible to receive digital TV transmission on an older antenna designed for analogue TV signals, the new TV antennas installed today are designed specifically for digital TV signals. Both types of antennas are likely to receive the same frequencies, however, if you are comparing them side by side, you will notice that the older style antennas for analogue TV are much larger, with more elements (‘arms’) and longer elements.
If you are unsure whether or not you are getting all the current digital TV channels offered by the networks, or if you need a new TV Antenna Installation, the team at Install My Antenna can help. For a free quote, give one of our friendly team members a call on 1300 800 123 today.