Digitisation of cable TV: What you didn't know

NEW DELHI, INDIA: Cable TVs in three metro cities-- Delhi, Mumbai and Kolkata--switched to digital mode on Thursday. However, the deadline for Chennai has been extended to November 5.

Here are answers to FAQs.

What is digital TV?

Digital TV transmits audio and video as digital signals, instead of the older analog system. All it needs is a digital TV service to your home, and a digital set-top box. (Music went digital in the 1980s, with CDs replacing analog cassettes and LPs, and finally everything giving way to iPods and MP3 players.)

Is this a good thing?

This is the biggest advance in television since color TV. It means far better quality of picture and sound, even in the lower-quality mode called standard definition (SDTV). And it allows high definition (HDTV), which wasn't possible on the older analog system. Digital also gives you individual channel subscription, and more bundled services, including data, games and other interactive services. And finally, it uses scarce radio spectrum far more efficiently.

What is this 'deadline'?

October 31 was the last date for Phase I of TV digitization in India - where all four metros switch to digital TV. As of November 1, all television in the metros is digital, and you will not be able to watch TV without digital equipment (barring Chennai, till November 5). This deadline was earlier March, then pushed to June, and finally October. In Phase II, 35 cities including Bangalore, Chandigarh and Pune, will switch over by March 2013. Phase III covers all other towns and cities (November 2014), and the rest of India is Phase IV (March 2015).

Am I affected?

You're affected if you have a cable TV service without a digital set-top box. If you use a satellite DTH service like Tata Sky, your STB is already digital, and you don't need to do anything. Also affected will be the few still watching Doordarshan ''over the air'' using a rooftop aerial: they will need either a TV set with a digital tuner (all LCD, plasma TVs and most TVs bought recently), or they'll need a STB with a digital tuner.

But why are they forcing this on us, with a deadline?

This can't be done without a full switchover to digital. Else they'd have to maintain two different systems, analog and digital, using up more spectrum. Second, broadcasters have been losing money because they don't get to know (and don't get paid for) the real subscriber numbers: in digital, it will be clear, and transparent.

What will the move to digital TV cost me?

Nothing, if you have a satellite TV service - it's already digital. If you have cable TV, the new digital set-top box is in the Rs. 600-800 range. That's a one-time cost. The service cost may go up at first - reports are coming in of a Rs. 200 monthly cost going up to as much as Rs. 300 - but you will likely save some month by selecting the specific channels you need, which was not possible on the older system.

What if I have more than one TV set?

For two TVs, your cost doubles - two set-top boxes, two subscriptions. This is where digital might cost you more, because cable operators might earlier have given you cheaper or flexible pricing in the same situation. With digital, every TV requires a set-top box. Some companies like Tata Sky offer a ''multi-room'' option with reduced monthly fees for additional connections in the same house. But that does not really save you much - for instance I pay Rs. 850 monthly for three Tata Sky connections in the house. (The only other option is to use a ''parallel'' RF link to display the same picture on the second TV. No hardware or monthly cost for the second TV then. However, you can't watch separate channels on the two linked TVs.)

What have other countries done?

India is late. Many countries have already moved from analog to digital. Some European countries made the transition earlier, between 2006 and 2011. The US made the move to digital TV in 2009, allowing only some low-power TV stations to continue with analog till 2015.

What technology and picture formats are used for digital TV?

There are several different technologies for digital TV. For satellite TV, India uses DTH (direct to home). For terrestrial transmission in India, Prasar Bharati has defined DVB-T2 (for HD and SD service in 19 locations. Broadcast HDTV uses a 16:9 picture at 720p (1280×720 progressive scan) or 1080i (1920×1080 interlaced scan). Your TV set may support an even higher-quality HD, called 1080p (1920×1080 progressive.Standard definition (SDTV) sends 4:3 pictures at 720×576 pixels for the PAL system in India (the US NTSC uses 640×480).

What is IPTV?

IPTV is when television service is delivered over an internet connection, which is often your phone line. This gives great flexibility, and services such as video on demand and time-shift (where you can see any program from the past week, for instance). But IPTV in India is slow (channel and other selections take time), of lower quality than digital SDTV, and does not support HDTV, which is why almost no one uses the IPTV services from Airtel, MTNL, etc, which are delivered over phone lines along with broadband service. (There is also ''internet TV'' or ''broadband TV'' such as Airtel's service, which lets you see TV on your computer, or on your TV using a media device like Apple TV. This may cost you a lot in broadband charges, however.)

Have people made the move to digital?

Mostly. As of November 1, Mumbai was reported to have switched over completely, and Delhi almost completely, but Kolkata still had over a fifth of cable TV homes on analog, and Chennai was even worse off with two-fifths on analog (Chennai has a high-court breather till Nov 5 for the switch). Half of India's 150 million TV homes use cable TV, and another quarter uses satellite (DTH) service.