How does a HD Television convert analogue signal to digital?

Question

And will the quality depend on the strength of your signal? If so and the outside aerial does not pick up a good reception what is the best solution?

Answer 1

HDTV's upscale analogue resolution by filling in the blank space by repeating lines, sort of like the analogue 100Hz TV's with line doublers. The quality depends just as much on signal strength as it does on a regular analogue television, but poor signal quality will be much more recognized because of the increased resolution. You can try using a better aerial and a signal amplifier, but beyond getting cable or satellite, there's not much you can do. If you have an HDTV, you should consider getting a STB that can receive digital signals. There are a lot of freeview HD stations you can get as it is and the quality of these are excellent. With digital, you either get the whole signal or you don't. No fuzzy static in between. If you're on the brink of losing the signal, it becomes blocky and freezes, but as long as you have a decent signal it will look just as perfect as if it was super strong.

Answer 2

The question you pose may be deeper than you expect. There are a few things you may not be aware of regarding your question.

The question of "How does HDTV convert analogue to digital." Can be answered pretty simply. The TV set or set top box, used by cable or satelite, have an embedded device called a ADC. This is an analog to digital convertor. See more here.

http://en.wikipedia.org/wiki/Analog-to-digital_converter

However, I get the feeling this isn't really the question you're asking. I'm guessing your wondering how we can get a "digital" signal off the air with a tuner. In that case you need aware of video broadcast standards.

The one we are familiar with is NTSC. This is the analog video broadcasting standard in the U.S. This type of video broadcast would require a ADC and possibly a codec to "encoder" "decoder" to show video on the HDTV. However, there is a new standard called ATSC which broadcast the HDTV/EDTV/SDTV in digital format. See more here:

http://www.hdtvprimer.com/ISSUES/what_is_ATSC.html

It is the case that the signal is broadcast using analog technology, but it's encoded in a format which translates into a digital stream of information the TV's codec will use to produce the picture.

So what does this mean? If you have an ATSC tuner for off the air HDTV signal, you'll pretty much either get a signal or not. The picture doesn't degrade gradually like an analog signal, it's pretty much there or not. There are cases were part of the picture comes through but it's pretty bad. This is because the TV is using a digital signal.

If however, you have some sort of NTSC tuner in the HDTV, then the reception will behave similar to what you're used to today.

Regarding the whole "upscaling" thing mentioned by a previous poster, that's really a whole different can of worms. Essentially the normal NTSC standard resolution video signal needs to be exploded to fit the HDTV screen. This usually results in a not so great picture because it requires quite a bit video processing.

Mike

Answer 3

you could lose image high quality, interior the experience that if the image format is more advantageous than what the show can deal with, the signal must be downconverted for show. yet you've not some thing to guage to. A signal is an indication, no matter if interior sight 480i or downconverted from 1080i or 720p. in case you position an HD show and an SD show section with techniques from section, i think you'd be able to inform the diff. on the grounds that we are talking about dropping your analog signal in Feb 2009, there are different themes related to image high quality (e.g., reception power and fading) that are more advantageous major than image downconversion. I have an Insignia container hooked as a lot as an early Nineties Samsung 32" CRT. the picture high quality is a lot more suitable through digital vs analog. the in elementary words element is that fringe reception for analog (snowy) only doesn't exist in digital (blockiness or not some thing).

Answer 4

IT REALLY DOESN'T IT JUST HAS A DIGITAL TUNER TO PICK UP THE SIGNAL.. AND WITH DIGITAL U EITHER HAVE A SIGNAL ITS NOT LIKE ANALOG WHERE IT WILL BE FUZZY BUT U STILL GET.. AND ALSO HOW THE DIGITAL SIGNAL TRAVELS IS IN SMALL WAVES SO IF YOUR ANTENNA IS FIVE FEET TO HIGH AR TO ONE SIDE IT CAN MAKE A BIG DIFFERENCE IN THE SIGNAL