3. Dvico HDTV Tuner

I used the Dvico FusionHDTV5 Lite (Figure 3) for this project. Dvico offers a wide variety of ATSC (High definition) TV Tuners. The FusionHDTV5 Lite is capable of capturing over the air high definition television signals by using a fifth-generation vestigial sideband tuner that receives the 8VSB modulation signal, which is used to broadcast free digital television to your standard over-the-air HD antenna. (8VSB is used in the United States and Canada.)

Figure 3: Dvico FusionHDTV5 Lite

The FusionHDTV5 Lite uses a unique type of software decoding engine. Unlike some of the cheaper software-based SD (standard definition) tuner cards that offload part of their capture process to the CPU, the FusionHDTV5 Lite instead offloads a portion of its processing tasks to the host computer's graphics processor. Since the graphics card is mostly idle when you're not using it to play a game, it's a perfect candidate to assist the tuner to capture video without needlessly bogging down the CPU.

In order for the graphics card to perform this function, it must be compatible with Microsoft's DirectX Video Acceleration (DXVA). This includes Nvidia cards that are equal to, or better than the Geforce4 MX series, and all of ATI's Radeon cards. If you don't have a compatible video card, the FusionHDTV5 Lite is capable of using the CPU to perform the encoding. However, this raises the system requirements from an 800-MHz Pentium III to a 1.6 GHz Pentium 4..

The FusionHDTV5 Lite outputs to a format called .TP. Generally, recorded HDTV file extensions are either .TP or .TS, which are standard MPEG 2 transport stream files. The card can also access and record SD (NTSC) television.

The Fusion Lite tuner is also capable of QAM decoding, which is the standard format in which non-over-the-air digital television is transmitted. Most QAM channels are encrypted and require a special cable card to unlock them. Some channels, however, are transmitted "in the clear," which means that QAM enabled tuners can access them.

Dvico offers several tuner cards that are capable of decoding "in the clear" channels. But Beyond TV does not currently support QAM tuning, nor does it plan to anytime "soon".