So during our Puget tech support/production meeting yesterday it was decided to stop carrying TV tuners for a while. The idea is that we need to step back and see what hardware is out there, what our customers are expecting, and if the two are compatible - and more importantly supportable. Since I'm sort of the resident HTPC expert here I wanted to put a little more info out there on exactly what a Vista-based home theater system is and is not capable of (as far as tuning in TV goes, anyways).
First off, let me run down what types of TV service modern PC tuner hardware will and will not work with:
Analog Cable - Almost every TV tuner out there is designed primarily to handle this, and it works very well.
Analog Over-the-Air - Because it is still analog, most tuners also work well with this. It will be a moot point soon, though, when the government-mandated switch to digital OTA goes into effect.
Digital Cable - This is where I see a lot of folks I talk to on a daily basis headed, and unfortunately tuner hardware is behind in this area. Tuners for it do exist, but they are very buggy (from what I hear) and require CableCards in order to work. The bigger problem, though, is that they are limited to only the industry "big-boys"; we can't sell them here at Puget, and even if we got our hands on some they require a special BIOS on the motherboard in order to function. You can get digital cable to work with an analog tuner by using a set-top-box, but because of the digital->analog->digital conversion you loose some quality and any HD signals will be downconverted.
Digital Satellite - Like cable, this only works (currently) by using a set-top-box. I have heard, though, that some of the larger satellite TV companies are working on USB-based tuner cards that will get rid of that step and allow for pure digital TV on computers. If this happens before cable tuners get their act together then it might actually be enough to get me to switch (I've always preferred cable in the past).
Digital Over-the-Air - This is one area where today's tuners can really shine. The higher-end models, like ATI's Theater 650 and a couple of Hauppauge's units, can tune in pure digital TV from free over-the-air broadcasts - all the way up to full HD/surround sound if it is being offered. The major thing to keep in mind here is reception: because of the nature of digital TV you will never get a "fuzzy" signal like you could with analog; you either get perfect quality or stuttering, unwatchable playback. If you are going for this make sure to have a nice antenna and check to see how your location is in terms of range/direction from broadcasters with a website like AntennaWeb.org.
Windows Vista's Media Center application will work with any of the methods I have described above. It comes with both the Home Premium and Ultimate editions of Vista, so most folks buying new computers today should have it. In fact, Media Center supports up to two digital and two analog tuners - so if you configure it properly it is quite a flexible platform. If you have a system with Media Center and are having any trouble, I've found TheGreenButton.org to be a great community resource.
There is also one more option for TV tuning that Vista isn't compatible with, but which you can in theory use via certain other 3rd-party media applications. I am speaking of digital cable with clear-QAM. QAM is an acronym for the way cable sends digital TV content, and it is usually encrypted - hence the need for CableCard-based tuners which can decrypt it for full digital cable usage. However, there is a chance that your local cable company is broadcasting some of its channels without encryption, or "in the clear" (hence 'clear-QAM'); if that is the case then a tuner which can recieve clear-QAM cable should let you view those stations. This is highly dependent on your local cable company branch, though, and I wouldn't necessarily expect their average help-desk folks to know if they encrypt or not.
Hopefully that short primer will help folks who might be looking to get a home theater PC. Feel free to discuss your thoughts on HTPCs and TV tuners below or in our forums - and definitely let us know if our decision to stop selling tuners in our computers for the time being will impact you!