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FAQs

Explanations of digital television terms

Digital Television Installation FAQs

What is free-to-air digital television?

Free-to-air television signals have broadcast programs in the analog format for over 50 years. Digital television transmits a broadcast signal by encoding it as 0s and 1s—the digital code used in computers.

Digital television signals can be compressed to provide four or more channels in the bandwidth required for one channel of current standard television, yet provide better sound and about five times more picture information (picture elements, or pixels) than conventional television. Digital television therefore makes more efficient use of spectrum and allows broadcasters to provide a greater range of features—such as multichannels, high definition television (HD TV) and an electronic program guide (EPG). Find out more about these terms further down this page.

What is digital switchover?

Digital switchover is the process of progressively turning off analog television services across Australia and replacing them with digital transmission.

Free-to-air television signals are currently broadcast in both analog and digital formats. At the end of the digital switchover all analog television signals (free-to-air television signals) across Australia will turn off and the broadcasters will provide only digital television signals.

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When did digital switchover commence?

Digital television transmissions commenced on 1 January 2001 in Australia's five major capital cities—Sydney, Melbourne, Brisbane, Adelaide and Perth.

Outside of the major metropolitan areas, digital television transmissions have begun in many regional centres and are continuing to be implemented across Australia.

What benefits does free-to-air digital television provide?

Digital television is a far more efficient and flexible transmission system than the current analog system. It allows broadcasters to offer viewers a range of new and different services.

Digital TV features include:

  • ghost-free reception
  • widescreen 16:9 pictures
  • standard definition pictures (SD)
  • high definition pictures (HD)
  • high quality audio and surround sound
  • multi-channel programming
  • closed captioning of programs for the hearing impaired
  • electronic program guides (EPGs) with 'now & next' program information for some channels
  • HD programs and HD channels
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What happens to my existing analog TV set?

Free-to-air broadcasters will continue broadcast both analog and digital signals (known as simulcast) until the completion of digital switchover. Therefore viewers can continue to use their current analog television sets to receive analog television broadcasts until this time.

When the switch off of analog television occurs in an area, viewers will require the addition of a digital TV set top box to their existing analog television to continue to receive free-to-air television.

Viewers using digital set top boxes will also have access to the other features of digital television—such as better picture quality, clearer sound and extra channels. However, as most existing analog sets have a 4:3 screen aspect ratio (shape), using a digital set top box with a 4:3 analog television set may affect the way widescreen (16:9) transmissions are displayed. Use of a widescreen display will enhance the digital experience.

To experience the full picture quality benefits of digital television, including access to high definition (HD) pictures, you will require an integrated digital television or display panel (known as an iDTV) with a HD tuner, or a television or display panel that is capable of displaying the HD television signal in combination with a set top box that incorporates a HD digital tuner.

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Can my 4:3 analog TV set display digital TV to its full effect?

No. Viewers can view digital television on a 4:3 analog television with the addition of a digital TV set top box, but will not see widescreen pictures displayed to full effect. Some set top boxes will give the option of viewing widescreen pictures in ‘letterbox’ format (black bars top and bottom) or ‘centre cut’ full screen format (with the 4:3 section ‘cut out’ of the 16:9 picture).

Will my video cassette recorder (VCR) still work?

Yes. During and after the simulcast period, you will be able to record the digital channel on view—provided your set top box or digital television has an analog output (as most do). VCRs will also continue to play back pre-recorded tapes. Many will find the picture quality of recorded digital programs is better than that of analog programs.

During the simulcast period VCRs will be able to record any analog program while a different digital program is being viewed. However, unless your digital set top box has two tuners, VCRs will not be able to record a separate digital broadcast from that which is currently viewed on the screen.

Current VHS video recorders will still only record VHS-quality pictures.

In some areas of Australia, the channel used by the video output may be the same as that used by a new digital television channel. In this instance, the video output on your VCR may need retuning or require the use of the audio/video (A/V) connection if present.

Download a simple outline of the purposes of different AV connections:

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Will digital televisions connect with VCRs, DVDs and sound systems, etc?

Yes. Although connection options will vary from manufacturer to manufacturer, all digital televisions are likely to have a range of different audio/video (A/V) inputs and outputs that offer connections to external devices such as VCRs, DVDs, sound systems and video cameras.

Download a simple outline of the purposes of different AV connections:

Will I need to upgrade my antenna?

If your antenna and antenna cabling is relatively new and in good condition, you should not need to replace your antenna. However if you experience digital reception problems, you should check with the antenna technician to confirm whether it is necessary to replace the antenna and cabling to receive uninterrupted digital television viewing.

Viewers in areas of poor analog reception should seek specialist advice about antenna requirements for digital television reception in their area.

See more information on the Installing digital television page.

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Why are digital TV pictures sharper than analog TV?

Analog television can suffer from multipath interference, which results in a ‘ghosted’ picture on your screen. Digital television is not affected by multipath interference and picture ‘flutter’ and so the digital result is a sharper, cleaner and clearer picture.

In areas of low signal strength, viewers of analog television may experience snowy pictures. In areas where there is inadequate signal strength delivered to a digital set top box, digital television may not improve the viewing experience when compared to analog.

Poor quality cables and connectors can also affect the digital TV picture and sound. The use of quality F-type connectors and quad shielded coaxial cables can provide optimum picture and sound performance. Contact your antenna installer for detailed information.

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Can I watch an analog program via a high definition set top box playing out on an analog definition TV set?

Yes. You can view high definition (HD) television programming by connecting a HD set top box to a standard (analog) television set. However, this will only deliver a picture quality equal to the display capability of the connected television screen. In order to view a high quality HD picture, you must connect an HD capable television or monitor.

Is audio better on digital television than on analog?

Yes. Australian television programming has traditionally been broadcast with FM stereo sound.

Digital television will carry MPEG digital stereo sound (the equivalent of CD quality) and/or Dolby Digital Sound (2, 4 or 5 channels) where available, thereby providing markedly superior audio services.

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What multichannel services are currently available?

There are currently five additional multi-channel services provided by the ABC, SBS, Seven Network, Nine Network and Ten Network:

What radio services are the ABC and SBS offering?

SBS currently provides two multilingual radio services with its digital television services.

ABC transmits its two internet radio services along with its digital television services:

Explanations of digital television terms

What are standard definition (SD) pictures?

Standard definition broadcast quality is superior to that obtained from analog television broadcasts, traditionally viewed on 4:3 television sets, and is ghost-free and in widescreen format.

The SD picture resolution is 576 lines x 720 active pixels @ 50Hz interlaced (576i).

The Government requires broadcasters to provide a digital SD signal at all times, even when high definition programs are broadcast. This is to ensure that viewers with SD receivers will always receive a digital television service, even when the higher quality high definition television signal is transmitted.

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What are high definition (HD) pictures?

High definition broadcasts have image resolution that is superior to SD pictures and to the existing analog television broadcast. HDTV offers a quality improvement of up to three times the improvement in detail.

Australian broadcasters are currently using four different levels of HD:

  • 1920 active pixels x 1080 lines @ 50Hz interlaced
  • 1440 active pixels x 1080 lines @ 50Hz interlaced
  • 1280 active pixels x 720 lines @ 50Hz progressive
  • 720 active pixels x 576 lines @ 50Hz progressive

The benefits of HD pictures at the highest resolution are particularly noticeable on larger screen sets and when using projection equipment.

HD pictures are also ghost-free and in widescreen format. When viewed on a HD capable television screen the viewer can enjoy cinema-quality viewing with Dolby Digital sound (where available with some HD programming).

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What is a set top box receiver?

A digital television set top box receives and decodes digital terrestrial television transmissions into a form suitable for display on analog television sets, display panels or other screen display devices such as computer monitors or projectors.

Analog television sets currently in use in Australia cannot display digital transmissions on their screens without a connection to a digital television set top box receiver.

The capability of a digital television set top box will depend upon its specifications.

A digital television set top box, when connected to a 4:3 analog television set, will usually give viewers an improved signal, better picture quality and multichanneling. Some set-top boxes may also provide viewers with datacasting services and video, audio and data enhancements.

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What does an electronic program guide (EPG) do?

An EPG is the electronic version of a printed program guide. Using your remote control you will be able to see on-screen ‘what's on now’ and ‘what's on next’ for all free-to-air services. You may also be able to search for a particular program by theme or category—e.g. sporting programs or movies.

Extra text and picture information (such as story line, episode description, etc.) can be called up as well. The EPG is always up-to-date and available at the click of a remote control button.

What is closed captioning?

Closed captioning provides deaf and hearing-impaired viewers with a text version of the dialogue, songs and sound effects included in television programs. The text is usually shown in a black box at the bottom of the picture. Current analog captioning is received on analog receivers with teletext capability. Captioning is normally ‘closed’ to viewers but can be accessed by those who need it.

Closed captioning does not interfere with normal viewing. Some digital television set top boxes and integrated digital televisions include closed captioning decoding capability.

Consumers intending to purchase a digital television set top box or an integrated digital television and use closed captioning should, before purchase, check on the set top box or integrated digital television’s capabilities.

Closed captioning of programming is incorporated in all English language news and current affairs programs as well as for all prime time programs (6.00pm to 10.30pm).

When available, closed captions can continue to be viewed on a standard PAL teletext-capable TV set that is tuned to analog broadcasts.

See more information about captions.

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What is an integrated digital television (iDTV)?

This is a television with in-built digital television tuner for receiving and displaying digital television transmissions.

A set with iDTV generally incorporates a high quality widescreen display and a high-level audio capability with appropriate audio/video connectors. It does not require a digital television set top box, although connection of an additional set top box could provide recording or other functionality.

What does multichannelling provide?

Because a digital television broadcast signal can carry much more data than an analog television broadcast signal it is possible for broadcasters to provide more than one channel of SD television programming at the same time. This is known as multichannelling.

The ABC and SBS currently provide one multichannel each that broadcasts a wide range of programs in addition to their main services. The free-to-air commercial broadcasters will be permitted to provide one SD multichannel each from January 2009 and to provide additional multichannels once digital switchover is complete.

Broadcasters are also offering a number of program guide and information data channels and some are providing HD programs or channels.

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What is the benefit of widescreen?

Digital television is broadcast in a native widescreen mode. Widescreen television has a different aspect ratio (ratio of width to height) than traditional analog television. The aspect ratio of a widescreen is 16:9, while Australian viewers have been accustomed to viewing a 4:3 aspect ratio since television began in this country.

Widescreen will, in many cases, literally mean you see more of the picture. Most movies are currently made in 16:9 and are converted to 4:3 to allow us to watch them on television or video, so there is a lot of information that you don't see on your television that you would see in the cinema version of the film. Live sporting events will benefit in particular from the extra detail and wider frame.

For some time now television production has been converting to widescreen. The majority of local television programming is now made in widescreen and increasing amounts of overseas programming shown in Australia is also being made available in a widescreen format.

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Digital Television Installation FAQs

Is a new antenna required to receive free-to-air digital television?

Generally viewers will have good digital reception of free-to-air digital TV from their existing antenna provided it is relatively new, is in good condition and is connected with good quality coaxial antenna cabling.

If the viewer currently receives good analog TV reception there should be no reason to buy a new antenna unless and until it proves to be inadequate.

If your digital television reception is not adequate you may need to replace your existing antenna and possibly the cables from the antenna to the wall socket.

More information about This link sends you off DBCDE's websiteDigital channel plans (DCPs) and This link sends you off DBCDE's websiteDigital TV Channels.

More information about installing digital television.

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What are the most common antenna installation problems?

Problems can occur in both domestic and commercial premises and are often caused during installation. They include:

  • The use of poor quality cabling, connectors and associated components
  • The inappropriate use of filters - stopping distribution of additional channels while attempting to reduce interference to analog
  • Failing to reduce Band I (Ch 2) and other channel levels causing overloading in amplifiers and TV tuners
  • Failing to reduce FM (Band II) signals causing interference to analog channels in Band III
  • The use of distribution amplifiers in lieu of masthead amplifiers
  • The use of masthead amplifiers in lieu of distribution amplifiers
  • Overloading of amplifiers - inadequate derating of output level and gain
  • In general carrying out installations without consideration of requirements as set out in Australian standards (AS 1367) for analog TV (which also apply to digital TV) 

With these potential problems in mind, it is important that installers:

  • Be equipped with good quality digital terrestrial field strength meters
  • Base their quotations and installations on surveyed field strengths
  • Test and take appropriate measurements of work as it is completed on site
  • Leave consumers with a written record of the reception characteristics of the site
  • Use good quality materials and correct installation methods at all times
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Which frequency bands should antennas be capable of receiving?

Analog and digital television services use the following frequency bands:

  • Band 1 VHF Channels 0-2 (Analog Only)
  • Band 3 VHF Channels 6-12
  • Band 4 UHF Channels 28-38
  • Band 5 UHF Channels 39-69

However not all bands will be used in each area. Likewise not all antennas receive all bands or channels.

A typical VHF antenna configuration is:

  • VHF Band 1 and 3 (providing Channels 2 and 6-12)

The typical UHF antenna configurations are:

  • UHF Band 4 and 5 (providing Channels 28 - 69)
  • UHF Band 4 only (providing Channels 28-38)
  • UHF Band 4 and Lower Band 5 (providing Channels 28-50)
  • UHF Band 5 only (providing Channels 39-69)

The typical combined UHF/VHF antenna configurations are:

  • VHF Band 1 & 3 and UHF Band 4 (providing Channels 2, 6-12 and 28-38)
  • VHF Band 3 and UHF Band 4 (providing Channels 6-12 and 28-38)

The bands used and therefore the antenna required depend on which transmitters service your area.

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  • Document ID: 80889 |
  • Last modified: 10 March 2008, 4:50pm