What Is The Purpose Of Television Going Digital In February?
Oct.02, 2009 in
HDTV Articles
I hear people say that it’s to “free up that particular frequency for other uses”. I don’t see this working because the signal may be digital when it hits your television, but the signal still has to be sent through the air in analogue. Is that the real purpose of the switch or is it something else. Supposedly the quality goes up when digital is used, but other than that I can’t see any real benefit.
What is this switch to digital really trying to accomplish?
October 2nd, 2009 at 8:28 am
DTV is transmitted digital. Analog has one carrier that is modulated with the entire program content. DTV has many carriers distributed across the bandwidth, each carries 4 bits of the digital data stream. Unlike analog, channels can be stacked together, like on a cable system. Over-the-air analog TV stations have to be separated by guard bands, for example no market can have channels 7,8,9,10,11,12, and 13 assigned because they would have massive mutual interference. They have to be separated, like 7,9,11 and 13 would work and the interleave channels are wasted. The change to digital means the entire TV band can be collapsed to utilize less channels. You may have not noticed, but channels 60-69 are already gone, assigned to other radio users. After February 52-59 will be gone as well. (channels 70-83 if you remember them, is where cell phones are now). Even within the new smaller TV band, any unassigned channel may be used for wireless digital (WiFi) type services because of the reduced occurrance of interference.
The money collected by auctioning off the old channels goes directly to reduce the national debt load on taxpayers. That is the real purpose for the change, to find new non-tax revenue streams to finance our federal government. So less taxes and better TV pictures a good combination.
October 2nd, 2009 at 8:32 am
The wave length of the analog signal is not the same. The signal does not have to be as strong because the tv only has to recognize 1 or 0. So the analog signal is narrowed + better quality. Better quality would be enough of a reason?
or … the government wants to control our minds more easily and make more money out of it somehow.. get your aluminum foil hats ready
October 2nd, 2009 at 8:50 am
Here is a comprehensive technical explanation…
The digital TV Channels are broadcast on a much higher frequency than Analogue TV Channels…
DAB radio and music station signals are ‘multiplexed’ with higher frequencies in order to ‘occupy’ a higher place on the spectrum…
October 2nd, 2009 at 9:03 am
it’s all so the government can make money!..every tv station has to pay millions to convert to digital. yes there will be a better picture..no static..either you will get the channel or not…no inbetween blurryness. but it is all for the government who controls all airwaves.
October 2nd, 2009 at 9:35 am
The stations in fact digitally transmitted. The digital transmission scheme allows the channels to fit closer together than it would for analog transmissions. That allows them reassign the stations to fewer overall channels. away from the upper UHF band, freeing it for sale and emergency services.
October 2nd, 2009 at 9:45 am
so the governed can sell more airwaves,
BTW, has been postponed for a while, not Feb,17.
October 2nd, 2009 at 9:51 am
The signal ISN’T sent through the air in analogue form. In fact from the camera to the final display it’s entirely possible for the signal to remain digital all the way!
Digital signals either provide perfect reception or none at all. This means an end to interference such as ghosting and pattern noise form other devices. The structure of the digital signal also means that many more channels can be exist in the same airspace. Currently the UK freeview system for instance is supporting well over 30 signals Vs the five that are only-just possible on analogue!
Eventually too it’s likely that High Definition services will be available on Freeview. Meaning much sharper pictures particularly for lager sets.
So, the benefits are sharper interference-free pictures (provided your equipment is set up properly!) and more channels. Some of the airspace may well be used for other purposes such as signalling and telecomms.
Changing to digital is very easy and cheap. Set top boxes are available from about £15 and, provided you have a reasonable picture at the moment from an outside aerial you WILL NOT need an aerial upgrade. Currently the service is working at reduced power, so after analogue is switched off there will be even more improvements made.