Unit 23 Telephones

Choose the best answers.

1.When you speak into the telephone , the waves of your voice are turned into ____. A.electrical sounds B.electrical signals C.light signals

2.The handle of an old telephone was used for ______. A.producing enough electricity to make a call B.connecting with another telephone C.getting better electrical signals

3.The job of an operator is _____. A.to wind the handle for customers and charge the phone calls B.to connect the two number, to time and charge the phone calls C.to mend telephones and telephone wires

4.____ can be used to send telephone signals over long distances by satellite. A.Sound waves B.Water waves C.radio waves

5._____ makes it possible for people at different places to hear one another speak. A.Redirection B.Conference meeting C.Call waiting

6.The service of redirection makes sure that ______. A.you can receive calls wherever you are B.all the telephone calls can be received by your secretary C.telephone calls can be recorded if you are not at your office

Some earliest telephones

the earliest telephones

The quality of theearliest telephones

At the beginning it was difficult to hear people over a long distance

The wires of theearliest telephones

thick ,heavy and expensive

How to make a telephone call in those days?

have to wind a handle to produce electricity.call the operator and tell her which number youwanted. The operator connected the two numbersand made a note of the length of the call and the charge.

The number of the earliest telephones

in 1877, 2600

the way to sendsignals

Metal wires were used to send electrical signalsin the past. The problems with electrical signals is that they get weaker and weaker as they travelalong metal wires.

some modern telephones

Ericsson

Concept Phones

This small computer-likeTelephone is still a mystery.

telephones of the present day

Improvements that have been made.

Instead of using metal wires to send electrical signals,very thin glass pipes,about 1mm wide,are used to send signals.Because light signalscan travel 150 km without getting weaker,andtheir signals is clearer, too.

cordless phones

It has no wires.it can be useful in office or in the factory. You can carry it with you and lookup the information your caller wants. That is,you can walk to a distant part of the office or factory to check the information without putting down the phone.

The number of telephones by 1990.

300 million

the ways in which new models of telephone can be used

1. conference calling

2. dialling

3. redirection

4. call waiting

How a telephone works?

When you speak into the telephone, the soundwaves of your voice are turned into electricalsignals. The signal is sent down a pair of wiresto the receiving telephone. There the electricalsignal is changed back into sound.

advantages of mobile phone:

It has no wires and can be carried about.

It is smart.

With the development of science and technology it will has more more and functions.

Today,Mobile Phone is not the very thing that you can call each other.It’s more than a telephone,a communicating tool.It develops to be multifunction and useful.With a Mobile Phone you can take photos ,listen to music,surf on the Internet,have meetings,watch TV,send E-mails and E-cards.

Watch Phone – a kind of mobile phone which looks like a watch.

I-mode telephone

They can download a lovely,Popular cartoon animal----Kitty Cat as the Screen Saver (屏保 ).

The I-mode uses can connect with the Internet frequently ,Send and receive E-mails, and seek the hotels and bars.

Photo-taking and song-listening PhoneYou can take photos and make them into characterful （个性化的）E-cards and send out.On the top of it is a recording lens( 录象镜头 ).The big clear screen can be convenient to browse the net page when you surf on the Internet.In addition,you can listen to music as you are enjoying the recorded video.

Mobile phones which can be used for surfing on the Intent .

Meeting—Plate– a Kind of phone usedfor conference calling,which has a big screen.The colored screen takes up three-fourths of the body.

NTTDoCoMo

64MB—Memory Download Mobile Phone

You can download songs.It is equippedInside with a 64MB RAM.The most attractive thing is that it has a256-color screen.

Mobile phones which can be used to listen to music.

PDA （掌上电脑） mobile phones

More and more people are using the kind 1.________of new-developed phone which is called mobile 2.________phone. It has not wires and can be carried 3.________in your pocket easy wherever you go. With 4.________the phone you may accept or make phone 5.________calls. People carry mobile phones are 6.________most businessmen,. Now with the further 7.________development of modern technology, it 8.________serves like a secretary that is quite 9.________fit the job. 10.________

a

newlyno

easilyreceive

who carrymostly

√as

fit for

Proof reading.