RADIO AND T.V
Radio was a marvelous electronic invention in 19h century. It was invent by Marconi in 1895. In this system of invention the electric waves could be sent in the air without the help of wire. This led to the invention of radio. Radio is used mostly as public medium, sending commercial broadcasts from a transmitter to anyone with radio receiver within its range, so it is known as a point-to-multipoint medium. Two-way radios, cordless telephones, and cellular radio telephones are devices that can both transmit and receive point-to-point messages.
Pakistan has greatly progressed in the field of broadcasting. Radio stations have been set up in private as well as in public sector. The government has formed Pakistan broadcasting corporation which controls and regulates transmissions of public sector radio stations throughout the country. At present there are 27 AM broadcast station, two FM broadcast stations and 21SW broadcast stations that broadcast programmes in seventeen languages daily. In 1997, there were 13.5 millions radio sets in the country.
TELEVISION (or TV)
TV is a term that refers to a more sophisticated broadcasting system in which sounds as well as pictures and live programs are transmitted from a TV Station. These programmes also travel in the form of electromagnetic waves and can be received at a television set. With the passage of time TV has attained more importance and particularly in urban areas it has overshadowed the radio service and today 70 percent of the world’s population is covered by TV. The source of income of radio and TV organization are license fees but they also run commercial to earn money.
Televisions transmit news and information. as well as entertainment. Commercial television is broadcast over very high frequency (VHF) and ultrahigh frequency (UHF) radio waves and can be received by any television set withing the range of the transmitter. Video cameras on computers now allow personal users to teleconference over the internet.
Pakistan television corporation was established in February 1967 and it has set up five television stations at Lahore, Karachi, Peshawar, Islamabad and Quetta. Today the total number of TV stations and TV broadcast centers in 22 while there are seven low power Reaters in the country. The estimated number of TV sets in the country in 1997 was 3.1 million which has been on the increase since then. More areas are being brought within the operational reach of PTV by installing boosters at different places. PTV has one channel for general purpose (PTV-1), one for educational purpose (called PTV-2) and a third called PTV-3. Besides, private entrepreneurs are also setting up their own TV channels and some of them have even started transmissions from Dubai or other foreign countries and applied to Government of Pakistan for grant of license for starting transmissions from Pakistan. These channels include ARY Digital, Geo Tv, Indus Tv, KTN, Uni-Plus T, Hum Tv, Aaj Tv etc.
One of the most favorable invention of science is cable network. It is a commercial service that links television to a source of may. different types of video programming using coaxial cable. The cable provider electronically unscrambles the signal and supplies the decoded signals by cable to subscribers. Personal satellite dishes are also a subscribe service. Fees are paid to the network operator in return for access to the satellite channels and in reply all the channels decoded by operators manages to show all the programmes on different channels. So the cable Television in complete source of entertainment.