TV Tuner Cards

GoodGearGuide Staff (Good Gear Guide) on 26 July, 2007 10:28

What is a TV tuner?

Digital TV has slowly gathered momentum in Australia thanks to its clear advantages over traditional analogue broadcasting. Digital set top boxes have come down in price over the last year but are still relatively costly. The good news is, if you've already got a PC you're a couple of short steps away from enjoying DVD-quality TV at home.

Australian TV networks have been broadcasting digital content since January 2001. Initially, the broadcast area was limited, but it has grown steadily, and now encompasses most of Australia's populated regions. Digital television brings a range of benefits to consumers, including support for widescreen broadcasts (in a 16:9 aspect ratio,) higher quality sound including the Dolby Digital 5.1 surround format, and high definition support, where broadcast images are at a higher resolution than standard TV or DVD.

Since 2001, the promise of digital television has been hampered by government regulations. One of the most exciting things about digital television was the potential of multi-channel broadcasting. This is where a television network could broadcast more than one channel in their transport stream. SBS had a service called SBS Essential that ran from October 14, 2002 to January 25, 2007. It was a support channel for SBS which gave constant news, weather and sports headlines as well as SBS programming schedules. Currently SBS has a dedicated news channel and ABC has an ABC 2, a channel with new and time-shifted content. Due to restrictions from government media regulations, the commercial channels have not been able to use multi-channeling to its potential. The second channels of the seven, nine and ten consist of nothing but scheduling information. However, many of the restrictions were lifted with the new media ownership laws passed through parliament on October 18, 2006. Whether they adopt the concept of multi-channeling remains to be seen.

Another, possibly more compelling, reason to move to digital is the fact that the signal isn't subject to interference. Because the stream is broadcast as digital MPEG-2 video (the same format used for DVD, albeit at a slightly different quality), the image is clear and crisp. What's more, the digital signal is broadcast in the same spectrum as analogue UHF, so the signal can generally be received without needing to upgrade the antennas. Making the switch to digital is simply a matter of installing a compatible tuner (as either a digital set top box or expansion card for a PC).

Where dedicated digital TV set top boxes are designed to sit in a lounge room and enable a regular TV to receive digital content, digital TV tuner cards are designed to receive digital television broadcasts for playback on a PC. They're relatively good value compared to dedicated set top boxes as the computer can perform some of the required signal processing, therefore simplifying the tuner.

Home Theatre PCs (HTPCs) have been popular in geek circles for years, but the relatively recent availability of MPEG-2 TV Tuners and Microsoft's Windows Vista and XP Media Centre Edition 2005 operating systems have sparked widespread interest. PC-based digital TV tuners come in three flavours: High Definition (HD), Standard Definition (SD) and a hybrid of the two. More on that later...