Wednesday, March 14, 2007

Direct To Home - From The Geostationary Orbit

Last Sunday an Indian satellite sitting 36,000 kms away kicked out the cablewala from our home. Perhaps its too early to say whether Tata-Sky is more dependable than the neighborhood cable-TV network but as far as technology goes, I’m truly impressed.

When I flick the remote now, there is a time lag before a picture appears on the screen. This might take some getting used to…but I guess that’s not bad for signals that go up and down 36,000kms!

I was also impressed by the way Tata-Sky is managing this whole operation. The advertising is neat; they have smart people on the customer-service lines; and the installation process is perhaps the best I have seen from a mass-media company.

We called the customer service line last week. A couple of days later, on a Saturday afternoon, a delivery boy came up with the Set Top Box (STB) kit and collected the payment; Rs. 2999 plus Rs. 550 for scratch-card worth three months of subscription (wonder why they call it “free”). The installation Techies turned up the next day with the dish assembly kit, coaxial cable roll, a portable TV, the contract docs and assorted tools.

Since the dish is installed on a roof that belongs to somebody else they first get you to sign a form that doubles as a no-objection certificate. They then clamber on to the rooftop along with the STB kit. As soon as a site is agreed, an extension cord is rolled down 25m to the ground floor to activate the drills. Once the base is screwed down, a compass and an inclinometer is used to fix the dish at 160 degrees South-East at an angle of 56 degrees.

The parabolic dish assembly has 20 components, including some unfamiliar things like “flanged nuts” and “AZ-EL brackets”. But the critical thing here is a device called the “Feedhorn” or the LNB (Low-Noise Block-down converter). This one picks electromagnetic waves from INSAT-4A and shifts the signals from the downlinked C-band (3500 MHz) and/or Ku-band (~11 GHz) to the L-band range (1600 MHz). The final Radio Frequency output from the STB to the TV is at 470 MHz.

The transformation of TV antennas has been quite amazing. Just until 10 years ago Directional Antennas dominated our rooftops. Aluminum rods shaped like stylized fishbone pointed towards a TV transmission tower in the city. When cable TV arrived they were left to the crows and pigeons or to some scrap-dealer interested in carting it away. The cablewala ruled for a decade. His roof had the biggest dishes; he decided your “bouquets” and charged as he pleased. His coaxial cables were strung haphazardly across streets and buildings, adding to the mess of overhead MTNL telephone lines and power cables. Where are these fellows now? They seem to have quietly disappeared into the night with their ladders and crimpers.

The old black coax cable has been tossed out; a new white one is in. The range of services and options certainly surpasses whatever the cablewala had to offer. But is the system durable? Can the dish & STB survive the heat and dust of Delhi? Will the entry of Reliance make the DTH industry as price-competitive as the mobile industry?

In any case, if this is the future, I like it :-)

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