Worldwide countries are switching to digital TV broadcasts. Digital broadcasts are set to begin 1 November 2008. This has several advantages over current analog TV broadcasts. A few standards exist for digital broadcasts, such as the DVB, ATSC, ISDB and DMB families of standards. DVB seems to be the most widely used standard.
Advantages of digital TV: (Mostly from common sense and Wikipedia article)
- No snowy pictures, ever
- Uses less bandwidth (more channels in same amount of spectrum)
- HD broadcasts possible
- Additional features possible (such as optional subtitles, multiple sound tracks, electronic program guides, etc.)
- Better picture and sound quality (depending on amount of compression used)
- In the case of very bad reception, no image will be seen, rather than a snowy image (However the image will remain perfect far longer than an analog signal of the same power)
- New equipment needed to receive digital signals
- The use of too much compression can degrade image quality
Existing analog televisions will not be able to receive digital broadcasts, but this will not affect them immediately. Analog broadcasts are planned to continue alongside digital broadcasts until 1 November 2011. However, when the analog transmitters are switched off (in order to allow reuse of the spectrum for other services) your existing TV and VCR will be useless without a special set-top box (STB) (similar to current DSTV decoders) This means that you will need to buy a separate set-top box for every TV / video machine if you want to be able to watch/record TV on more than one channel (each set-top box will be able to receive a single channel that will be selected with its own remote).
Most of the televisions available in South-Africa at the moment are only capable of receiving analog signals, which means that if you do not buy additional equipment you will be unable to use your new TV in three years' time. Of course things such as consoles and existing set-top boxes will continue working.
It is hard to find information on the standards selected for digital broadcasting in South-Africa, but DVB-T and Eureka 147 (for radio) seem likely based on government's switchover site. In the case of radio however it was decided that FM broadcasts are to continue indefinitely.
If you want to buy a new TV/VCR it seems like a good idea to wait till November in order to receive confirmation of the selected standard and to see how digital broadcasting performs.
Government should have done more to inform the public about the switchover and should have banned the sale of analog televisions without warning that they will be useless in three years' time.
Additional links:
Speech on switchover
Update (2008-09-10): I have received confirmation that some form of DVB-T will be used, with a MPEG-4 codec. The SABC might want to force a conditional access (a form of DRM) system, which would mean that even with a digital TV, you still need a STB with all its disadvantages. If a STB is required the only advantage of a digital TV above a analog one is likely to be better picture quality. The "security features" in the STB is probably related to a conditional access system.
Media coverage of the migration process has improved as well.
It looks like the 1 November switchon date is likely to be postponed.
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