Satellite TV through your PC

There are also plenty of websites that will help you calculate the correct alignment, such as www.satsig.net/ssazelm.htm.

If you do have a dish, then check out the box, ‘Satellite basics’. It’s not as easy as you think to share it between an existing receiver and your PC.

You’ll also need to decide what type of receiver to use. In our visits to high-street retailers, all we could find was a PCI satellite card, but there are also receivers available that can connect via USB or Firewire, which may be easier for some installations, and crucial if you’re using a laptop.

Choosing the right card or adapter isn’t just a matter of deciding if you wa nt an internal or external model, though. There are other things to bear in mind as well. For example, some cards will come with a remote control, or with AV inputs, so you can pass signals from a DVD player or VCR through them, giving your PC a more media centre feel.

There are also two other key factors. First is encryption. It’s used to protect pay channels, and in the satellite world, what looks like a PC Card slot on a receiver or adapter is known as a Common Interface Slot. Equipment with one of these can accept a Cam, or conditional access module, into which the smart card for a subscription package works. It means, in effect, that you can pick the Cam for the service you want to subscribe to, and you’re not forced to buy a receiver from the TV company.

The big fly in the ointment – and a potential stumbling block for UK users – is Sky; there’s no official Cam available for Sky’s encryption, so you usually need to have one of its receivers and a card, even for free-to-view channels, such as Channel 4 or Five.

We say ‘usually’ because a programmable Cam, called the ‘Dragon Cam’, can emulate Sky’s encryption, but the card still needs to be put in a genuine Sky box from time to time for regular updates, even if it’s a free card. For most people in the UK, this really means it’s best not to bother with a CI slot and Cam, and simply use satellite on your PC for FTA channels.

The second factor you need to consider is high definition. We mentioned earlier that the satellite standard is called DVB-S, which is only half the story. There’s a newer standard called DVB-S2, which is so far used by only a few channels, but is likely to be used by more in future as they move to HD. The BBC’s HD service uses DVB-S now, but may switch, so it may be wise to invest in a card or add-on receiver that supports DVB-S2.

Software considerations
It’s also worth considering the software you want to use on your PC. If you want to use a particular program, rather than just accepting what comes with a satellite card or adapter, check the compatibility list – some programs are very picky, and having the Windows BDA (Broadcast Driver Architecture) drivers is no guarantee a card will work with other software. Decide which software you want to use and choose a card or external satellite adapter that’s known to be compatible.

Also, remember that Windows Media Center (both XP and Vista versions) still has no native support for DVB-S, so you can’t bank on using that as a solution. There are hacks and workarounds documented at http://thegreenbutton.com, but as not everyone will have the requisite version of XP or Vista we recommend starting with a third-party solution.

If you want to watch HD channels, you’ll also need a codec that understands the H.264 Mpeg4/AVC format used on many of them. It’s hard to give a definite figure for how powerful a PC you’ll need for this. It will depend on the satellite card you have and whether your graphics card can help out with the decoding, but we’d suggest no less than a 3GHz Pentium 4 with hyperthreading for smooth playback. Newer dual-core machines will perform much better.

There are three main codecs available for playing back the HD streams – CoreAVC, Cyberlink’s H.264 codec, included with PowerDVD 7, and Elecard’s Moonlight H.264. Expect to pay about £30 for a codec if you don’t have one already. If you’ve already equipped your computer for playback of HD discs, it should be capable of managing satellite, since the broadcast bit rate is lower than you’ll find on a disc.