CATHODE ray tube (CRT) television sets may be standing on the ledge before being dunked into coffins and have their epitaphs written in technology graveyards, but not quite soon.

In three years’ time, the Government TV and radio network RTM will be offering 19 free-to-air channels through digital terrestrial broadcasting. And contrary to common belief, the CRT set can display digital content.

“What you need is a set-top box to decode the digital signals,” said RTM’s deputy director general (engineering) Abu Bakar Abdul Rahim.

RTM’s nationwide digital terrestrial broadcast in 2012 will offer a standard-definition resolution to over 95 per cent of the population, which means the public will be able to enjoy DVD-quality sound and visual on TV.

Of the 19 channels, Abu Bakar said, one channel will be dedicated to full high-definition resolution programmes.

“We are looking at documentaries, international news and sports events, as some news stations like Al-Jazeera and Korean Broadcasting System have already produced their programmes in HD.”

Trial runs of digital terrestrial TV broadcasting (DTTB) by RTM began in September 2006 to 1,000 respondents. Due to overwhelming feedback, the network has installed another 1,000 set-top box decoders in Klang Valley homes. The respondents are currently receiving six TV channels, including TV1, TV2, sports and music, and seven radio channels through the decoders.

After upgrading five studios, an ingest room (where all programmes are stored and labelled before transmission), a master control room and a multiplexer suite at Angkasapuri last year, RTM began its digital broadcasting through the Kuala Lumpur Tower linked to the Ulu Kali tower in Genting Highlands, covering the central west coast region of the peninsula.

Digital broadcast is more efficient in data transmission than analogue signals. The latter needs separate transmitters, but DTTB is compressed into a single bandwidth and transmitted as a single channel. The set-top box decoder will unpack the single channel into strands of multi-channels, in RTM’s case,

19 channels.

To explain the concept, Abu Bakar used the analogy of a bus on a highway. An analogue signal is like a bus, which is allowed to carry only one passenger, so TV1 and TV2 will have to hop onto different buses. The digital signal, on the other hand, is like a single bus ferrying 19 channels simultaneously.

What’s more, the digital video broadcasting (DVB) system used by RTM is so smart that it can recognise, label and calculate, frame by frame, how much bit rate on the shared bandwidth each channel would need. If on a bus, one can imagine how big a seat the passenger would need.

For instance, if TV1 is screening a talk show, it would need less bit rate than TV2 which is showing the fast action of a Formula 1 race. But if the next frame cuts to the F1 presenter and TV1 is showing a news clip of war and famine, the DVB system will immediately alter the compression to allow optimum quality on both channels. Imagine a flexible seat to accommodate the passenger’s needs on a bus.

It is sophisticated, but technology is dynamic, Abu Bakar said. “We will have to continue adapting to changes.”

And broadcasting full HD would mean a passenger with a larger seat on the bus.

Last year, RTM experimented by broadcasting the Beijing Olympics in full HD, and respondents gave a thumbs-up to the intricate visual detail and superior sound received on their TV sets.

One of the engineers at RTM described the experience as: “The visual detail was astounding. You could see every strand of the athlete’s windblown hair and the raindrops bounced off the track on tight shots. The thunderous applause filled the room as if you were part of the crowd. It was so breathtaking that nobody moved away from their seats during the opening and the track events.”

To experience HD, the audience will need a good plasma or LCD TV plugged in with an equally good home theatre system. Here, the CRT models would not be able to deliver the visual detail, nor the Digital Dolby 5.1 surround sound.

The advantage of DTTB, which is received by a regular antenna, over digital satellite broadcast is that the transmission will not be interrupted by bad weather, and RTM will be installing an additional 1,000 sub-stations to iron out pocket areas blocked by higher grounds.

The network is targeting 2015 for a complete analogue shutdown.

If frugality is the rule of the day, you may still want to keep your faithful TV sets before switching to the sleek plasma or LCD panels.