高中牛津英语模块七Unit1 Reading

The evolution of video and sound devices

Early history of TV

The first public TV broadcasts were made in the USA in 1925.Later,in 1928,the first long-distance TV broadcast was made between the UK and the USA.Regular public broadcasting followed shortly afterwards,first beginning on 11 May 1928 in New York and on 20 August 1929 in London.

Many different people contributed to the development of TV.Most early TV broadcasts were made using a system developed by John Logie Baird in the UK.However,his system was very primitive and had many drawbacks.An American,Philo Farnsworth,made important breakthroughs in the development of TV in the late 1920s and early 1930s.Modern TVs use many of the principles first discovered by Farnsworth.

John Logie Baird constructed the first colour TV in 1928,but it was not until 1938 that the first colour TV programme was broadcast.It took more than two decades,though,until 1951,for regular colour TV broadcasts to begin in the USA.Regular colour TV broadcasts were delayed in the UK until 1967.However,within a short time nearly all TV broadcasts were made in colour,and within five years more colour TVs than black-and-while TVs were being used.

The modern age:satellite TV

Satellite were used to broadcast TV beginning in 1962.Satellites allow TV to be broadcast live over vast distances,with everyone receiving the same broadcast at the same time.They also make TV accessible to people who live far away from cities,and satellite dishes can often be seen distributed throughout the countryside and remote areas.Of course,only a small percentage of people own satellite dishes.However,most people still benefit from satellite TV,as local TV companies broadcast the signals they get from satellite receivers to the population living nearby. Early history of sound recorders

It all began in 1877,when Thomas Edison made ths first recording of a human voice on his invention,the record player,Early record players used round tubes to record on.However,in 1887 Emile Berliner,a German living in the USA,invented a record player that used discs as alternatives to tubes,and so the modern record player was born.The first record players had to be wound up by hand and only played records that were two minutes long.Times surely have changed!

Sound and video recorders

In 1928,the first tape recorders used to copy sound were in Germany.Most early recorders employed steel tape to record on,which made them heavy and difficult to use,or paper tape,which was easier to use but often broke.It was not until the early 1950s that most tape recorders began using plastic tape as they do today.Meanwhile,electrical components eventually bacame so small that,by the late 1960s,portable cassette players were developed,along with video recorders which were used by TV stations.By the late 1970s,video recorders small and cheap enough for home use were introduced.

Sound and video go digital

In 1982,the first CDs were made available.CDs are often used for storing and playing music bacause they have a much better sound quality than traditional records and cassettes.In 1993,the VCD was born,and in 1995,the DVD was invented.The DVD is now the standard for recording

and playing back video.

The future With the development of digital technology,sound and video can now be stored on a PC,on the Internet,or using some form of portable storage.This will soon make records,cassette recorders,CDs,DVDs and even TVs things of the past.Technology is now changing faster than most people can keep pace with.Who can foresee what the future will bring?