Here in the UK there are a few ways to receive digital TV. Some of them are free (after an initial outlay for equipment) others are based on a subscription model. Here are some of the most common ones:
- Digital terrestrial, received through a suitable TV antenna (DVB-T)
- Cable, in most cases through Virgin Media (DVB-C)
- Sky (DVB-S)
- Freesat (DVB-S/DVB-S2)
My MythTV installation is currently solely using a dual-tuner DVB-T receiver to record TV. However we are right on the edge of the closest transmitter’s reach with no usable overlap with any other transmitter, so at best our signal is spotty.
As spring progressed and the trees regained their leaves our signal has gotten weaker and weaker to the point that about 90% of recordings fail due to a lack of a signal lock or a very weak signal producing something that’s unwatchable.
The TVs in the house cope slightly better, but still suffer a lot from a broken signal. With digital being all-or-nothing compared to analogue’s degrees of static snow, it’s either you can watch something or you can’t… unless we change to the analogue tuners in the TVs, which we often have to.
We are being forced to consider alternatives, either to back up terrestrial or replace it completely.
I’m keen to keep to things which can be used legally with MythTV, which would rule out Sky and Virgin Media which essentially bind you to using their hardware. The benefits of those two services however is that they have a more complete selection of channels as well as the option to upgrade to significant bonus content, compared to the one remaining alternative – Freesat.
Freesat was launched recently by a collaboration between the BBC and ITV. Most of the transmissions are in Standard Definition (SD) with a small sprinkling of High Definition (HD) services. More channels are expected to sign up, but at the moment there’s all of the UK BBC and ITV channels plus Channel 4 but at the moment no Channel 5 (who seem to insist on transmitting encrypted signals). Also there are none of the UKTV-owned channels including Dave.
Freesat is transmitted unencrypted over DVB-S & DVB-S2, both of which can be received by a computer using an appropriate satellite receiver card. Naturally I’ve been keeping my eye out on eBay for such cards, and there are usually a few on at a time. I’ve not bought any just yet and I won’t until a decision is made for sure that we’re going for Freesat rather than the next alternative, cable.
DVB-S2 is used for carrying HD programmes. It is relatively new, so although there are PCI cards out there cable of receiving the transmissions, the software for Linux hasn’t caught up yet. MythTV is in the early stages of including support, and some basic drivers are available. The cards come with software for Windows, but that’s not much use for a distributed MythTV-based PVR. I’m hoping that at least I can get DVB-S working for recording and such, then upgrade to DVB-S2 when it’s reliable. In the meantime HDTV can be watched on a normal set-top box.
Before Freesat came on the scene, as already mentioned the next alternative was cable from Virgin. In my investigations it quickly became apparent that connecting a DVB-C card (a rare thing in the UK) to Virgin’s cable network was not a good idea since it would almost guarantee disconnection of all services including my 20 meg broadband.
To keep within the T&Cs of that means using the analogue output from the V or V+ box, connecting it to a capture card and then doing digital->analogue->digital conversion. The result of this would be relatively low-quality video and audio, at a limited resolution (SD only). An IR transmitter would need to be used to control channel changing, and since it uses the only externally-available tuner you couldn’t watch one channel on TV and let another record on the same box. It’s certainly not an elegant way of doing things.
If we were to go for Sky, a similar thing would probably have to happen, although with a little work it may be possible to get a PCI DVB-S card to work with it, provided it had support for a decoder card so that the signal could be decrypted.
In the likely event that we decide to go for Freesat, the cheapest solution would be to do a complete self-install. However the easiest solution would be to pay for installation of a single-room service. We will need a 4 room service however, so the plan is currently to pay for a single room installation at £80, then buy a quad LNB and run the 3 other cables ourselves. That way we don’t have to worry about getting the correct size dish, mounting and positioning it. Apparently there’s some satellite-grade coax around somewhere that should do the job.
There will probably be 2 tuners in a machine that will do the recording (possibly boron) and the other 2 runs will go to the living room and the master bedroom.
Naturally there will be photos and such if/when the project takes place.
