Monday, November 12, 2012

1972, TV services were extended to Mumbai, which was then Bombay

Until 1975, only 7 Indian cities were covered by TV

How did TV broadcast start in India?

In September 1959, Delhi became the first Indian city to get TV telecast facility. It took nearly six years to start regular services. By 1972, TV services were extended to Mumbai, which was then Bombay. In the early days, TV took a long time to reach other parts of the country as until 1975, only seven Indian cities were covered by television. Television gradually penetrated across the country and today India boasts of one of the world's largest TV broadcast networks. Initially, terrestrial television was used for TV broadcasting in India. The system, which date backs to the beginning of TV broadcasting in the world, does not involve satellites to transmit information. Instead it depends on transmitting, receiving and TV antenna. The TV requires a tuner that could convert radio signals to audio and video.

What is satellite TV?

Unlike terrestrial TV, satellite television is based on delivering programmes by the means of communication satellite. These signals are received by a parabolic reflector type outdoor antenna, typically referred to as a dish antenna. The signals could be obtained either by large community antennas and then distributed by coaxial cables or directly by direct to home ( DTH) antennas designed for individual reception. The satellite system is capable of transmitting all forms of broadcasting signals.

What are the other methods of TV broadcasting?

TV broadcasting can be divided into two main categories — analogue and digital. There are three types of analogue television systems used around the world — NTSC, PAL and SECAM. Similarly, digital TV broadcasting is done by four different systems — DVB-T, ATSC, ISDB-T and DTMB. These systems, which are used in different countries, are significantly different from each other. The main differences are in details like conversion into broadcast and then video format as well as the methods used for transmission of broadcast signals. To resolve conflicts between various TV systems, countries typically adopt a single broadcasting system as their national standard.

How is digital broadcasting different from analogue?

A digital signal transmits the information in binary code which is zero or one. The analogue system converts the information into electromagnetic waves. A digital TV has several advantages over analogue sets. Most importantly, it takes far lesser bandwidth. This enables the broadcasters to provide more channels. Because of increased space in the transmission bandwidth, the broadcaster could provide additional information like program guides, additional language option, subtitles and so on. Apart from this, digital signals also have superior picture quality.

What is the new government move aimed at?

Across the world, countries are switching from analogue to digital broadcasting. At present, broadcasters in many countries are operating by delivering simulcast services where broadcast is made available to both digital and analogue consumers. As digital telecast is becoming popular across the world, it is generally believed that the coming years will witness a complete switchover from analogue to exclusively digital broadcasting. The switchover varies from country to country. For instance, in India and the UK it will be implemented in various stages. Specific regions will switch on different dates. The 'switch off' disables analogue TVs from receiving broadcasts and hence a set-top converter box is required to receive digital signals.