extracted_text:
АСТАНА ҚАЛАСЫНЫҢ
БІЛІМ БАСҚАРМАСЫ
«КӨЛІК ЖӘНЕ
КОММУНИКАЦИЯ КОЛЛЕДЖІ» МҚКК

ОҚУ –
ӘДІСТЕМЕЛІК КЕШЕНІ
«Кәсіптік
ағылшын тілі» пәнінен
1309000 «Оптикалық
және электронды құрал-жабдықтар»
мамандық бойынша
арналған

Әзірлеген оқытушы:
_________ К.А. Рахимбаева
«Орыс және ағылшын тілдері»
кафедра отырысында қарастырылған
№ ___ хаттама «___» _______ 201___ ж.
________ М.Т. Тлеубаева

Астана қаласы
2017 ж.
Кіріспе

            Соңғы
уақытта колледждерде шет тілінде үлкен көңіл
бөлініп келеді. Себебі қазіргі танда басқару
аумағындағы мамандардың біліктілігі көп жағдайда
басқа ел азаматтарымен еркін қарым-қатынасқа
түсіп,іскерлік келіссөздер жүргізе білуімен бағаланады.
Сондықтан жа оқу орындарында осы деңгейге сәйкес болу
үшін ағылшын тілін  көлемді түрде оқытуға
бағытталады.
            Сіздердің
назарларыңызға ұсынылып отырған оқу
құралы колледж студенттеріне кәсіби ағылшын тілінен
оқу – әдістемелік комплексінің негізі болып табылады.
Кәсіби
ағылшын тілі пәні бойынша құралып отырған
бұл оқу құралы екінші курс
«Оптикалық
және электронды құрал-жабдықтар» мамандық
бойынша оқитын студенттерге арналған.
            Осы
оқу құралы мамандыққа бағытталған
материалдар бойынша сөйлеу әрекетінің өзара
байланысқан түрлерінің  (оқу, аудару, жазу,
сөйлеу) принципі негізінде құралған. Материалдардың
лексикалық мазмұны мемлекеттік білім стандарты және
техникалық колледждерге арналған «Кәсіптік ағылшын
тілі»  пәнінің бағдарламасының талаптарына сәйкес
келеді. Оқу құралы 4 бөлімнен тұрады. Онда
танымдық, сипаттық және кәсіби бағыттағы
мәтіндер қамтылған және мәтіндерге байланысты
тақырыпты бекітуге жаттығулар енгізілген. Жаттығулар
шығармашылық және жартылай шығармашылық
сипаттағы тапсырмалардан жасалған, бұл лексикалық
минимумды меңгеруді және сөйлеу жазу дағдыларын
дамытуды қамтамасыз етеді.
            Әр
бөлімдегі жаттығулар ауызша қарым-қатынасқа
бағытталған, яғни оқу, аудары,
сұрақтарға жауап беру, әңгімелеу, қосымша
ақпараттың көмегімен өз білімін толықтыру.        Оқу
құралымен жұмыс жасау барысында студент елтануға
байланысты ақпараттармен өз білімін байытуға,
мамандыққа байланысты сөздік қорын кеңейтуге,
іскерлік қарым-қатынастағы сөйлеу мәнерінің
ерекшеліктерін меңгеруге, мамандыққа қатысты тексттерді
оқып,аудара білуге, келіссөздердер жүргізуге, іскерлік
хаттарды дұрыс жаза білуге және де анықтамалық
әдебиетпен, сөздікпен жұмыс істей білуге мүмкіндік
алады.

Түсіндірме жазба

Бағдарлама
оқу жоспарларына сәйкес жасалған, техникалық және
кәсіптік білім берудің үлгілік, оқу жоспарының
моделі негізінде әзірленген.
Оқу жоспарына үлгі қалпында «Кәсіптік
ағылшын тілі» төмендегі мамандық үшін:1309000
«Оптикалық және электронды құрал-жабдықтар», барлық сағат көлемі -87,
теорилық-15 сағат, практикалық -72 сағат, 3 семестр-45
сағат, 4 семестр-42 сағат,  2 бақылау жұмысы, 2
сынақ қарастырылған.
Қазақстан Республикасының орта кәсіптік
білім берудің мемлекеттік  жалпы білім беру үлгіқалпына
сәйкес жұмыс бағдарламасының жүзеге асырылуында 4
сағат бақылау жұмысы өткізілуі
қарастырылған.
Жұмыс бағдарламасының негізгі
мақсаты-қазіргі заманға сай мамандарды толыққанды
дайындауды қамтамасыз ететін шетел тілін тәжірибе жүзінде
толық меңгерту. Сонымен қатар бұл бағдарлама
студенттерді шектеулі сағат саны көлемінде тіл білімінің
белгілі бір бағдарламасын оқыту қарастырылған.
Болашақ маманды оқытудың гуманизация тезисі
ақпаратты кәсіптік  ретінде, сондай ақ этно-мәдени
және жалпы адами тұрғыдан қамту арқылы
жүзеге асырылады. Бағдарлама бұл мамандық бойынша
іскерлік тілдің негізінде кәсіптік лексика, фразеологиялық
айналым және терминдерді кәсіптік бағыттағы
мәтіндерді сөздікпен аударуды,  кәсіптік
қарым-қатынас жасауды қарастырады.
Студент кәсіптік бағыттағы мәтіндерді
сөздікпен аудару және лексикалық, грамматикалық
минимумды, сонымен бірге шет тілінде сөйлесудің 2 қарапайым
дағдыларын меңгеруі тиіс.
Кәсіптік ағылшын тілі пәнін оқып
үйрену негізінде арнайы жалпы кәсіптік пәндер «Байланыс жүйесі», «Қазіргі заманғы
байланыстың дамуы»,«Телефон арқылы сөйлесу», «Қазіргі
заманғы электроника» және т.б арасында тығыз байланыс
жасалынады.
Бағдарламаның мазмұнын оқып үйренуде
Қазақстан Республикасының тіл саясатының концепциясы,
«Қазақстан Республикасының тіл туралы заңы» ретінде
ағылшын тілі оқыту мәселесінің нормативтік
құжаттарын еспке алу қажет. Кәсіптік ағылшын
тілін үйретудің мақсаты орта кәіптік оқу орнында
қоғамдық-саяси мәтіндерді терминологиялық
сөздік көмегімен мамандық бойынша әдеби
мәтіндерді, ауызекі сөйлеу дағдысын белгілі лексикалық
және грамматикалық материалдар негізінде сөздіктің
көмегінсіз жеңіл көркем мәтіндерді оқу және
түсіну бағдарламада қарастырылған.
Бағдарламаны жүзеге асыру барысында дидактикалық
және көрнекі құралдар: грамматикалық
үлгілер, оқу және оқу-әдістемелік
құралдарын қолдану ұсыналады.
           Студент төменде көрсетілетін
тақырыптар бойынша лексикалық минимумды білуге міндетті:
-
«Байланыс жүйесі», «Қазіргі заманғы
байланыстың дамуы»,«Телефон арқылы сөйлесу», «Қазіргі
заманғы электроника».
-
жоғарыда
көрсетілген тақырыптар бойынша теміржолға қатысты
терминдерді дұрыстап айта білуі қажет;
-
Осы шақтың,
өткен шақтың және келершақтың жай
түрін;
-
Continuous  (Present, Past, Future) шақтарын;
-
Perfect (Present, Past, Future) шақтарын;
-
Инфинитивті(активті және
пассивті);
-
ParticipleI, Participle II формаларын;
-
Модальды етістіктер және
олардың эквиваленттерін;
-
Ағылшын тіліндегі
сөздің құралуы;
-
Шартты бағыныңқы
сөйлемдер;
-
Етістіктердің және
жоғарыда көрсетілген шақтардың жасалу ережелерін;
Студент меңгереді:
-
Сөйлеу әрекетінде
өзінің білім қорын қолдана білуі және
қабілеті мен дағдысын көрсетуі қажет;
-
Техникалық
мәтіндерді оқи және мазмұндап айта және аудара
білуі қажет, грамматикалық жаттығуларды дұрыс орындауы
тиісті,сұрақ қоя және сұраққа жауап
бере білуі қажет, диалогтарды шет тілде құрастыра білуі
тиісті.
       Студент ағылшын тілінің фонетикалық,
лексикалық  және  грамматикалық дағдысын меңгеруі
тиісті.

Оқу
бағдарламасының мазмұны
Бөлім 1.
Байланыс жүйесі.
Тақырып 1.1
Қазақстан Республикасы.
The climate of Kazakhstan. Territory of
Kazakhstan. Power recourses in Kazakhstan.
Грамматика: Жай осы шақ. To be, to
have, to do етістіктерінің жай осы шақта сұраулы, хабарлы
және болымсыз түрінде қолданылуы.
Тақырып 1.2
Қазақстан республикасының мемлекеттік рәміздері.
The state Symbols of the
Republic of Kazakhstan.
Тақырып 1.3
Байланыс жүйесінің даму тарихынан кейбір кезеңдер.
Invention of the first electromagnetic telegraph. The
first telephone history.
Грамматика: Жай өткен шақ. To
be, to have, to do етістіктерінің жай өткен шақта
сұраулы, хабарлы және болымсыз түрінде қолданылуы.
Тақырып 1.4
Телефонның даму тарихы.
The development of the
telephone history.
Тақырып  1.5.
Телефон қоңырауы қалай жеткізілді.
Телефонның таралу бағыты. Телефон
белгілерің берілуі.
Грамматика: Жай келер шақ.
Will/shall етістіктерінің жай келер шақта сұраулы, хабарлы
және болымсыз түрінде қолданылуы.
Тақырып 1.6. Радио
байланыс.
Radio is a device that
transmitters and receivers by electromagnetic wires.
Тақырып 1.7.
Радионың пайда болуы.
Alexander Stepanovich Popov demonstrated
his first radio receiving set in operation.
Грамматика: Созылыңқы осы
шақ. To be, to have, to do етістіктерінің созылыңқы осы
шақта сұраулы, хабарлы және болымсыз түрінде
қолданылуы.
Тақырып 1.8. Радио
толқыны арқылы хабар жеткізгіштер.
The function the radio
transmitter is to convert the electrical power received from a primary source
into radio-frequency energy modulated with a signal for transmission by means
electromagnetic waves through space.
Тақырып 1.9. Радио
құрылғы.
The receiver performers
the function of converting the current in the receiving antenna into the
intelligence contained in the transmission.
Тақырып 1.10.
Электрондық терминдердің және қысқартылған
сөздердің сөздігі.
The definitions in this glossary refer the
words only as they are used in this book.
Тақырып 1.11. Телекоммуникацияның
қысқартылған терминдерінің сөздігі.
Telecommunication Abbreviations
glossary.

Бөлім 2. Қазіргі
заманғы байланыстың дамуы.
Тақырып 2.1.
Электорондық ғасырдың бастамасы.
The electronic is a field
of engineering and applied physics dealing with the design and application of
electronic circuits.
Грамматика: Созылыңқы
өткен  шақ. To be, to have, to do етістіктерінің
созылыңқы өткен шақта сұраулы, хабарлы және
болымсыз түрінде қолданылуы.
Тақырып 2.2.
Қазіргі заманғы байланыстың дамуы
The Internet, phones, telegraph, cell
phones, radio, television are all the means of communication or
telecommunication.
Тақырып 2.3.
Компьютердің шығу тарихы.
The history of computer.
The first computer
Грамматика: Созылыңқы келер
шақ. Will/shall етістіктерінің созылыңқы келер
шақта сұраулы, хабарлы және болымсыз түрінде
қолданылуы.
Тақырып 2.4.
Компьютер дегеніз не?
Computer is a device for
processing information.
Тақырып 2.5. Компьтерлік
құрылғылар.
The hardware are the
devices composing a computer system.
Грамматика: Аяқталған осы
шақ. To have, to do етістіктерінің аяқталған осы
шақта сұраулы, хабарлы және болымсыз түрінде
қолданылуы.
Тақырып 2.6.
Компьтерлік құрылғылар.
The types the computer
hardware.
Тақырып 2.7. Windows XP
бағдарламасы.
Windows XP makes the way
you and your computer interact with internet easier.
Грамматика: Аяқталған
өткен шақ. To have, to do етістіктерінің
аяқталған өткен шақта сұраулы, хабарлы және
болымсыз түрінде қолданылуы.
Тақырып 2.8.
Компьютердің қызмет түрлері.
The types computer operation.
Тақырып 2.9.  Бағдарламалардың
түрлері.
Software is final
computer system component.
Грамматика: Аяқталған келер
шақ. Will/shall етістіктерінің аяқталған келер
шақта сұраулы, хабарлы және болымсыз түрінде
қолданылуы.
Тақырып 2.10.
Спутниктік  және телебайланыс түрлері.
 The evolution
process of first telecommunication.
Тақырып 2.11.
Бақылау жұмысы.
Студенттердің білім деңгейін
тексеру.
Тақырып 2.12.
Сынақ. Өлеңдер мен жұмбақтар.
Студенттердің білімін тест
арқылы тексеру. Атақты ағылшын ақындарының
өлеңдерін оқып үйрену. Жұмбақтарды
оқу барысында қолдану.
Бөлім 3.
Телефон арқылы сөйлесу.
Тақырып 3.1.
Сенімен телефон арқылы байланыса аламын ба?
Work with a partner.
Questions and answers.
Грамматика: Тұйық етістік. Тұйық етістіктің сөйлемдерде қолданылуы.
Тақырып 3.2.
Телефонмен сәтті сұхбат.
Some tips to make
telephoning in English less stressful.
Тақырып 3.3. Маған
сен соны әріптеп айта алар ма едің?
What are these
symbols called in English?
Грамматика: Ырықты және ырықсыз етістегі тұйық етістік.
Тақырып 3.4
Ықыласпен тыңда!
Make the sure the place
where you are telephoning isn’t too hot, too cold noisy comfortable.
Грамматика: Осы шақтағы
есімше. Есімшенің сөйлемдерде қолданылу амалдары.
Тақырып 3.5. Мен
сізге сол жөнінде қайта хабарласамын.
Choose the best voicemail
greetings.
Грамматика: Өткен
шақтағы есімше. Есімшенің сөйлемдерде қолданылу
амалдары.
Тақырып 3.6. Пайдалы сөз
тіркестері.
Useful phrases of taking and leaving
messages.
Тақырып 3.7. Сізге
қай уақытта ыңғайлы болар екен?
Time  expression in English.
Грамматика: Модальды етістіктер және
олардың баламалары.
Тақырып 3.8.
Пайдалы сөз тіркестері.
Useful phrases in different
situations.
Тақырып 3.9. Мен
сол үшін өте қатты өкінемін.
Agree or disagree to
complaints.
Грамматика: Ағылшын тіліндегі
сөздің жасалуы.
Тақырып 3.10.
Өткендегі әңгіме не туралы еді?
Work with the partner.
Interview with your partner. Questions and answers.
Грамматика: Ағылшын тіліндегі
сөздің жасалуы.
Тақырып 3.11.
Пайдалы сөз тіркестері.
Useful phrases making a phone call.
Бөлім 4.
Қазіргі заманғы электроника.
Тақырып 4.1.Гальваникалық
элементтер. Батареялар.
Types of cells. Diagram of a zinc-carbon
cell.
Грамматика: Шартты
сөйлемдердің түрлері ( I, II,III).
Тақырып 4.2. Радио. Техникалық
қысқартылған сөздер
Diagram of
electromagnetic waves.
Тақырып 4.3. Транзистордың
сипаттамасы.
The table from supplies
catalogue of transistor characteristics.
Тақырып 4.4.
Теледидарлық байланыс.
Using electrical signals to carry
messages.
Тақырып 4.5.
Теледидарлық байланыс.
Differences old and new
phones.
Тақырып 4.6.
Ұзақ қашықтықтарға мәліметтерді
жеткізу.
The transmission of
information over long distances.
Тақырып 4.7.
Ұялы телефондар. Жұмысқа орналасу. Түйіндеме.
Which buttons would you
press when you use cell phones.
Job hunting. C. V.
Resume.
Тақырып 4.8  Факс. Лексикалық
және грамматикалық тақырыптарды қайталау.
The development history
of facsimile machines.
Тақырып 4.9.
Жылдық қорытынды бақылау жұмысы.
Мақал-мәтелдер.
Студенттердің білім деңгейін
қорытындылау. Мақал-мәтелдерді үйрену және оларды
оқу барысында пайдалану.
Тақырып 4.10.
Сынақ. Өлеңдер мен жұмбақтар.
Студенттердің білімін тест
арқылы тексеру. Атақты ағылшын ақындарының
өлеңдерін оқып үйрену. Жұмбақтарды
оқу барысында қолдану.
Тақырыптық
жоспар

№

Бөлім мен
  тақырыптардың аты

сағат
  саны

оның
  ішінде

теориялық

тәжірибелік

Section 1 «Communication system»

22

10

12

1

Theme 1.1. Republic of
  Kazakhstan
Present Indefinite
  Tense.

2

0

2

2

Theme1.2. The state
  Symbols of the Republic of Kazakhstan.
Grammar practice.

2

0

2

3

Theme 1.3. Some steps from the
  history of communication system
Past Indefinite Tense.

2

2

0

4

Theme 1.4 The
  history of telephone.
Grammar practice.

2

0

2

5

Theme 1.5.
  How telephone call travels. Future Indefinite Tense.

2

2

0

6

Theme 1.6. Radio
  communication.
Grammar practice.

2

0

2

7

Theme 1.7. The Invention of Radio.
Present Continuous Tense.

2

2

0

8

Theme 1.8. Radio transmitters.
Grammar exercises.

2

0

2

9

Theme 1.9. Radio Receivers.
Work on vocabulary.

2

0

2

10

Theme 1.10. Glossary of electronic
  terms and Abbreviations

2

2

0

11

Theme 1.11. Abbreviations in
  telecommunications.

2

2

0

Section 2  «The development of
  modern communications»

23

5

18

12

Theme 2.1.
  Development of Electronics. Past
  Continuous tense.

2

0

2

13

Theme 2.2. The Development of modern
  communication. Grammar
  practice.

2

0

2

14

Theme 2.3. The History of Computer
  Development.
Future
  Continuous Tense.

2

0

2

15

Theme 2.4. What
  is the computer?
Grammar practice.

2

0

2

16

Theme 2.5. What is hardware?
Present Perfect Tense

2

2

0

17

Theme 2.6. What
  is hardware?
Grammar practice.

2

0

2

18

Theme 2.7. Windows
  XP
Past Perfect Tense.

2

0

2

19

Theme 2.8. Computer
  operations. Types of data. Grammar
  practice.

2

0

2

20

Theme 2.9. Types
  of software.
Future Perfect Tense.

2

2

0

21

Theme 2.10.
  Types of software.
Grammar practice.

2

0

2

22

Theme 2.11. Control work.
Review of previous grammatical and lexical themes.

2

0

2

23

Theme 2.12. Test (Grammar and
  lexical themes). Riddles and poems.

1

1

0

III семестрдегі
  сағат саны

45

6

39

Section 3. «Telephoning»

22

0

22

24

Theme 3.1. Shall I put you through?
The Infinitive.

2

0

2

25

Theme 3.2.Successful telephoning.
Work on vocabulary.

2

0

2

26

Theme 3.3. Could you spell that for me?
Active Infinitive and Passive Infinitive.

2

0

2

27

Theme 3.4.Get active with you listening.
Participle I.

2

0

2

28

Theme 3.5. Let me get back to on that.
Participle II.

2

0

2

29

Theme 3.6.  Useful phrases.
Grammar practice.

2

0

2

30

Theme 3.7.When would suit you?
Modal verbs.

2

0

2

31

Theme 3.8. Useful phrases.
Grammar practice.

2

0

2

32

Theme 3.9. I’m very sorry about that.
Word formation.

2

0

2

33

Theme 3.10. How does that sound?
Word formation.

2

0

2

34

Theme 3.11. Useful phrases.
Grammar practice.

2

0

2

Section 4.  «Modern electronics»

20

0

20

35

Theme 4.1. Batteries.
If clauses I-II-III.

2

0

2

36

Theme 4.2. Radio.
Technical abbreviations.
Grammar practice.

2

0

2

37

Theme 4.3. Transistor characteristics.
Grammar practice.

2

0

2

38

Theme 4.4. Telecommunication.

2

0

2

39

Theme 4.5. Telecommunications: historical review.
  Grammar practice.

2

0

2

40

Theme 4.6. Transmission lines

2

0

2

41

Theme 4.7. Cellphones.
Job hunting. C.V.   Resume.

2

0

2

42

Theme 4.8. Fax. Review of previous
  grammatical and lexical themes.

2

0

2

43

Theme 4.9. Control work. Proverbs.

2

0

2

44

Theme 4.10. Test (Grammar and lexical themes). Riddles
  and poems.

2

0

2

IV семестрдегі
  сағат саны

42

0

42

Пән бойынша
  барлығы

87

15

72

Теориялық
сабақтар жоспары

№

Сабақ
  тақырыбы және қысқаша мазмұны

Сағат саны

Әдебиет

1

Some steps from the history of
  communication system.
Past Indefinite Tense.

2

В. С. Радовель
Ю.Голицынский

2

How telephone call travels.
Future Indefinite Tense.

2

D. G. Smith
R. Murphy

3

The Invention of Radio.
Present Continuous Tense.

2

В. С. Радовель
R. Murphy

4

Glossary of electronic terms and Abbreviations

2

Eric H. Glendinning

5

Abbreviations in telecommunications.

2

Eric H. Glendinning

6

What is hardware?
Present Perfect Tense.

2

И. П. Агабекян  Ю.Голицынский

7

Types of software.
Future Perfect Tense.

2

И.
  П. Агабекян  Ю.Голицынский

8

Test (Grammar and lexical themes).
  Riddles and poems.

1

Ю.Голицынский
Л.Д. Цесарский

Барлығы

15

Практикалық
сабақтар жоспары

№

Сабақ
  тақырыбы және қысқаша мазмұны

Сағат
  саны

Әдебиет

1

The Republic of Kazakhstan.
Present Indefinite Tense.

2

Толмачева Л.Ф.
Ю.Голицынский

2

The state Symbols of the Republic
  of Kazakhstan. Grammar practice.

2

В. Франк, А. Досмаганбетова
R. Murphy

3

The history of telephone.
Grammar practice.

2

D. G. Smith
R. Murphy

4

Theme 1.6. Radio communication.
Grammar practice.

2

В. С. Радовель
Ю.Голицынский

5

Radio transmitters.
Grammar exercises.

2

В. С. Радовель
Ю.Голицынский

6

Theme 1.9. Radio Receivers.
Work on vocabulary.

2

В. С. Радовель

7

Development of Electronics.
Past Continuous tense.

2

В. С. Радовель

8

The Development of modern communication.
Grammar practice.

2

В. С. Радовель
R. Murphy

9

The History of Computer.
  Development. Future
  Continuous Tense.

2

В. С. Радовель
Ю.Голицынский

10

What is hardware?
Grammar practice.

2

И.
  П. Агабекян  R.
  Murphy

11

Windows XP
Past Perfect Tense.

2

И. П. Агабекян
Ю.Голицынский

12

Computer operations. Types of data.
Grammar practice.

2

И.
  П. Агабекян
R. Murphy

13

Types of software.
Grammar practice.

2

И.П. Агабекян

14

Satellites and Telecommunications.
Review of previous grammatical and lexical themes.

2

Eric H. Glendinning
Ю.Голицынский

15

Control work.

2

Ю.Голицынский

16

Shall I put you through?
The Infinitive.

2

D. G.
  Smith
Ю.Голицынский

17

Successful telephoning.
Work on vocabulary.

2

D. G. Smith
To learn by heart terms

18

Could you spell that for me?
Active Infinitive and Passive Infinitive.

2

D. G. Smith
Ю.Голицынский

19

Get active with you listening.
Participle I.

2

D. G.
  Smith
Ю.Голицынский

20

Let me get back to on that.
Participle II.

2

D. G.
  Smith
Ю.Голицынский

21

Useful phrases.
Grammar practice.

2

D. G.
  Smith Ю.Голицынский

22

When would suit you?
Modal verbs.

2

D. G.
  Smith И.
  П. Агабекян

23

Useful phrases.
Grammar practice.

2

D. G.
  SmithИ. П. Агабекян

24

I’m very sorry about that.
Word formation.

2

D. G.
  Smith
И. П. Агабекян

25

How does that sound?
Word formation.

2

D. G.
  Smith
И. П. Агабекян

26

Useful phrases.
Grammar practice.

2

 D.
  G. Smith
И.
  П. Агабекян

27

Batteries. If
  clauses I-II-III.

2

Eric H. Glendinning
Ю.Голицынский

28

Radio. Technical abbreviations.
Grammar practice.

2

Eric H. Glendinning
Ю.Голицынский

29

Transistor characteristics.
Grammar practice.

2

Eric H. Glendinning

30

Telecommunication.

2

Eric H. Glendinning

31

Telecommunications: historical review.

2

Eric H. Glendinning

32

Transmission lines.

2

Eric H. Glendinning

33

Cellphones. Job hunting. C.V.
Resume.

2

Eric H. Glendinning

34

Fax. Review of previous grammatical
  and lexical themes.

2

Eric H. Glendinning

35

Control work. Proverbs.

2

Ю.Голицынский
ИД «Кочевник»

36

Test (Grammar and lexical themes). Riddles and
  poems.

2

Ю.Голицынский
Л.Д. Цесарский

Барлығы

72

Мазмұны

Кіріспе
............................................................................................................................................
2
Пәннің
жұмыс бағдарламасы
.........................................................................................................3
Unit 1 Communication system
Kazakhstan…………………………...............................................................................................15
Some steps from the history of communication system
…………………………………………..18
The history of telephone …………………………………………………………………………..20
How telephone call travel …………………………………………………………………………23
Radio communication ……………………………………………………………………………..25
The invention of Radio ……………………………………………………………………………26.
Radio transmitters………………………………………………………………………………….28
Radio Receivers……………………………………………………………………………………30
Glossary of electronic terms and Abbreviations
…………………………………………………. 31
Job hunting…………………………………………………………………………………….. ….72
Unit 2 «The development of modern communications»
Development of Electronics………………………………………………………………………..76
Development of modern communication.
……………………………………………………........77
Computer …………………………………………………………………………………………..78
Hardware …………………………………………………………………………………………...80
Software …………………………………………………………………………………………….81
Unit 3. «Telephoning»
Successful telephoning……………………………………………………………………………...82
Dialogue «Telephone conversation»………………………………………………………………..85
Unit 4. «Modern
electronics»
Batteries……………………………………………………………………………………………..87
Cellphones…………………………………………………………………………………………..88
Fax…………………………………………………………………………………………………..89

The Republic of Kazakhstan.
General
data
Area:
2,724,900 sq.km.(l,052,125.56sq. km.)
Capital:
Astana
Population:
16,870,000
Largest
cities: Almaty (1.3 mln -),
Karaganda (0,633 mln -), Shymkent (0,5 mln
-)
а) Topical
vocabulary. Read and practice the pronunciation.
• share   v - бөлу
• desert   n шөл
• resources [ri'so:siz] n байлық
• uranium  n -уран
• deposit [di'pozit] n – қазба орны
• gas [gas] n - газ
• rename [n'neim] v –ат беру
• reservoir  n – жинақ
• former ['fo:ma] - өткен
Text
                                     KAZAKHSTAN IS MY MOTHERLAND
Kazakhstan was established as the Republic of Kazakhstan in December 1991. The country is the second largest of
the former Soviet republics with a total land area of over 2,724.900 million square
kilometers. This country shares its border with the Russian Federation to the north and north-west; to
the east with
China and to the south with the central Asian republics of Kirgizstan,
Uzbekistan and Turkmenistan.
The Ural River flows through the western portion of Kazakhstan to the Caspian Sea. The central region of the
country includes the Kazakh Steppe to the north and deserts of central Asia in
the south-west. The Altai mountains can be
found in the east.
The country is rich with mineral resources such as copper, gold, iron,
lead, nickel,
silver, tin, uranium and zinc with deposits of oil and natural gas.
The largest city of Kazakhstan is Almaty which lies to the south-east
of the country near the
border with Kirgizstan and China. Almaty was the capital until December 1997
then it was moved to Akmola, 850 kilometres to the north-west. In May 1998 Akmola was renamed
Astana, the Kazakh word for capital. The population of Astana stands currently at 700,000.
Peaceful and generous, the land of the Kazakhs has always been famous
for its hospitality. And it is not by accident, located on the crossroads of
two ancient cultures — Europe and Asia.
Today residents are happy to share that famous hospitality and to show
the visitors the Alatau mountains with famous Medeu; the singing sands of the Altyn Emel National Park; Kapchagai -
reservoir on the Hi river, the lakes and pine forests of Kokshetau; and Akhmed Yassaui Mausoleum in Turkestan, a lot of places of interest in
Astana. Kazakhstan, with the world's ninth largest area, has many such beautiful places and a
rich culture.
The official
language is Kazakh and Russian is the language of international communication.
1.      Independent work. Fill in
the table.

3. Comprehension check

True (T)

False (F)

a. Kazakhstan is the
  second largest country of the former
  Soviet Union.

b.
  Kazakhstan doesn't share its border with China.

c.
  The country is rich in mineral resources.

d. The population of Astana is not expected to increase.

e. Residents are happy to share hospitality with their visitors.

f. The official language is Kazakh.

g.
  Russian is the language of international communication.

IV. Confirmation of new material:
Answer the questions
When was Kazakhstan established?
2. What total land area has our Republic?
3. What countries does Kazakhstan share its border with?
4. Where does Ural River flow?
5. What
does central region of the country include?
6.Where
can be found the Altai mountains?
7.What
mineral resources is Kazakhstan rich with?
8.What
are the largest cities of Kazakhstan? What can you say about Almaty?
 9.When
Akmola was renamed Astana? What is the population of Astana?
10.What are the residents happy to share with
visitors and to show them?
Communication system

Topical vocabulary
Inherited (to inherite)                                                мұра
After the break up of the Soviet
Union                     бұрынғы Кеңес Одағы
In a complex state                                                     жағдайы
нашар
Was not independent (to be   -was)                           тәуелсіз
емес еді
Went through Moscow          (to
go-went)               Мәскеуге арқылы өткен
An independent country                                            тәуелсіздік
мемлекет
Under the control                                                      бақылауында
Many drawbacks                                                       көптеген
кемшіліктер
Communication links (a link)                                    байланыс
құралдары
railway and  motorway routes           (
a route)         темір жол және автомобиль жолдары
“Iron curtain”                                                            «Темір
қоршау»
 Single air flight                                                        тек әуе қатынасы жүзеге
The outer world                                                         сыртқы әлем
No broadcasts                                                            ешқандай ТВ хабар тарату
Reconstruction of Aktau sea port                              Ақтау теңіз портын салу
Appeared ( to appear)                                                пайда
бола
A water route to  Iran                                                Иранға су жолдары
Participates in the implementation of
TRASEC       ТРАСЕКА жобаларды іске асыруға қатысады
Establishing                                                               нығайту
Europe, Central Asia                                                 Европа.Орталық Азия
Pipelines transport                                                     мұнай
құбыры
World market                                                            Әлемдік
нарық
Transport  technology                                               көлік
технологиясы
No companies dealing ( to deal)                               кез-келген
компаниялар тартылған
Transport
research and development institutions    Көлік зерттеулер мен даму
институттарының
Normative
base,  standard and regulations              нормативтік база, стандарттар мен
реттеу
Challenges of the time                                              сағатына
қажет
 must undergo restructuring
ұшыраған болуы тиіс
Update                                                                       жаңарту
Maintinance                                                               техникалық қызмет көрсету, пайдалану
Via
арқылы

About
communıcatıon system of Kazakhstan
            The transport and
communıcatıons system of Kazakhstan ınherıted  after the
break up of  the Sovıet Unıon ıs ın a complex  state.
At the time of the Sovıet Unıon our transport
was not independent. It as under the  control of different ministries located
in Moscow.At that time  all communıcatıons went through Moscow. Now
Kazakhstan is an independent  country and it is obvious that its  transport
system has many drawbacks.
In the past
Kazakhstan and Central Asia had communıcatıon links  with no one but
Russia.  There were  eleven railway and sixty  motor way routes to the  Russia
and no routes leading beyond the ”Iron curtain”.The only railway station
Druzhba on the Chinese border was  not  in operation for political reasons.Not
a single air flight linked Kazakhstan with the outer world. There were no
broadcasts from abroad to say nothing in the Internet access.Now the situation
changed rapidly. The gates to China  are openedwith thr railways and motor
roads.
 At present with
the reconstruction of Aktay sea port there appeared a water route to Iran.A
pilot project on passinger and freight railway communıcatıons with
Istanbul via Tashkent  and Teheran is under way. Kazakhstan participates in the
implementation of TRASECA project aimed at  eatablishing
transport corridors from Europe to the Pacific zone via  the Caucasus, Central
Asia, Kazakhstan and China. Pipelines
transport Kazakhstan’s  oil to the world markets.Air routes link the two
capitals practically with all neighboring countries. The World Web access is
becoming  an every day practice  with more and more Kazakhstanians.
Answer the questions.
1. What transport and communications
system did Kazakhstan inherit after the break up of the Soviet Union?
a) a complex state      b)not
independent      c) control from Moscow and communications
2. What drawbacks has transport
system of Kazakhstan ?
3.  How is the situation in Kazakhstan
changed now?
a) opened gates to China        b)
reconstruction of Kathy sea port   c) pilot project and freight railway
communications          d) TRASECA project of transit corridors      e) oil
pipeline transport to the world market             e) world web access
4. What own problems has every type
of transport communications in Kazakhstan?
a) no transport  research and development    institutions
 b) No companies dealing with transport technology
c) Normative base, standard and
regulations

Telephone
Vocabulary note
an instrument                                                 құрал
sends and receives                                         жіберуге және алуға
voice messages                                              дауыстық хабарлар
by means of electric  current                         Электр тогын пайдаланып
one  of most valuable means of
communications      байланыс ең маңызды
құралдарының бірі
far and sound                                                 алыс
дыбыс
telephone can send information                     ақпаратты
жібере алады
from one computer to another                       бір
компьютерден екіншісіне
artificial satellites                                           жасанды
спутниктері
are installed or carried                                   орнату
connect with                                                  байланыстырады

Telephone is an instrument
that sends and receives voice messages, usually by means of electric  current.
It is one of   most valuable means of communications. In just a few second, you
can telephone person across the street, in another part of the country, or on
another continent. The word telephone comes from two Greek words
meaning far and sound.
In its most basic form, a telephone
enable  people to talk with one  another at distances beyond the range of the
human voice messages, but  also written words, drawings, photographs and even
video images, in addition telephone can send information from one computer to
another.
Telephone in people’s
homes are just one part of a vast, complex telephone network also includes
large computers, tremendous length of cooper wire and hair thin strands of
glass, cables buried in the ground and laid along the oceans, radio
transmitters and receivers and artificial satellites orbiting far above the
earth by means of wires that run through the houses and buildings. A small clip
connects each telephone to the wiring. Other phones are installed or carried in
bag or packet. Such phones connect with the network by radio.
Alexander Graham Bell
invented the telephone in 1876. Today hundreds of millions of telephones serve
people all over the world.

Complete as in the text.
Telephone is an instrument that …
It is one  of   most valuable means …
The word telephone
comes from two Greek …
In its most basic form, a telephone
enable  people to talk …
Telephone in people’s homes are just
one part of a vast, complex telephone network also includes
Answer the questions:
What is telephone?
Is it one of   most valuable means of
communications?
Where does the word telephone come
from?
How can person talk with one another?
What does complex telephone network
include?
Who and when invented the telephone?
What is telephone for you?
 Does the mobile telephone play great
role in your life? Why?

History of telephone
On the 14 February in 1876 American
of the Scottish origin Alexander Bell gave in Bureau of patents of the USA a
request on the vehicle that he named a telephone to them.  By only two hours
later similar order was placed a by other American on the last name Gray. In
England Bell with success continued demonstrations collecting plenty of public.
Finally, “delightful telephone presentation” was given to the queen and her
family. The supporters of Bell, taking credits, created in reply “New England
telephone of company” and plunged into a fight. By the result of fight,
however, creation became   at the end of 1879 incorporated “Bell of company”.
Bell placing New York to
Chicago telephone call in 1892. Credit for the invention of the electric
telephone frequently disputed, and new controversie,  over the issue have
arisen  from time to time. As with other inventions such as radio, television,
the light bulb and the computer, there were several inventors who did
experimental work on voice  transmission over a wire and improved on each other
ideas. Antonio Meucci, Johann Philipp Reis, Elisha Gray, Alexander Graham Bell,
and Thomas Edison among others, have all been credited with pioneering work on
the telephone.
An undisputed fact is that
Alexander Graham Bell was the  first to be awarded a patent for the electric
telephone by the United States Patent and Trademark Office in March 1876. That
first patent by Bell was the master patent of the telephone, from which other
patents telephone devices and features flowed.
By the rainy morning of
Augusts, 4, 1922 in the USA and Canada on a minute all telephones were off.
America buried Alexander Graham Bell. The 13 million telephones sets of various
kinds and constructions in honor a great inventor.
Answer the questions:
What is telephone?
Is it one of   most valuable means of
communications?
Where does the word telephone come
from?
How can person talk with one another?
What does complex telephone network
include?
Who and when invented the telephone?

How telephone call travel

Types of telephone
dial telephone, rotary dialing
telephone;                   Телефон нөмірін теру;
pushbutton telephone, touch-tone
telephone             түймені басу телефон;
pay phone, public phone;                                          телефон-автомат;
mobile phone, cell phone / cellular
phone;               мобилді телефон ,ұялы  телефон;
cordless / wireless phone,
radiotelephone;                сымсыз телефон, радиотелефон;
satellite phone;                                                          спутник
телефон;
IP telephone, softphone (software
phone);                компьютер  арқылы телефон;
VoIP (Voice over IP);                                               IP-негізделген желілер
арқылы дауыс;
WiFi phone (Wireless Fidelity).                               Интернет
желісіне қол жеткізумен сымсыз телефон.
2.Telephone parts and
accessories
the base unit / the base;                                             база

the receiver / the handset;                                         тұтқа
the microphone;                                                         микрофон;
the dial; the buttons;                                                  диск;
кнопка;
the redial button;                                                       қайта теру батырмасы;
the mute button;                                                        өшіру түймешігі;
the hold button;                                                         күту түймешігінің ішіне;
the bell; the hook;                                                      звонок;
рычаг;
the telephone plug;                                                    телефон
штекері;
the telephone jack;                                                     телефон  розеткасы;
the headset; earphone, earphones;                             басты  телефон; наушник, наушник;telephone
cord; telephone cable; telephone wire;
answering machine; fax machine;
modem;               автоответчик; факс; модем;
speakerphone;                                                            байланыс
атышулы құрылғы;
caller ID / caller identification.                                 қоңырау шалушының
қоңырау шалушы идентификаторы.

Dialogue
Woman 1: Hello, Mrs Smith. How’s
your Susie?
Woman 2: She’s fine, thank you. Mrs Jones. And how’s Jonny?
Woman 1: He’s OK. Thanks.
He can play the guitar now.
Woman 2: Oh. Susie can play
the guitar. And she can play the piano too.
Woman 1: Well, Jonny can’t play the piano but he can sing.
Woman 2: Oh, can he? Susie can sing,…
Woman 1: Can Susie dance?
Woman 2: Yes, she can. Can
Jonny dance?
Woman 1: No, he can’t. He doesn’t
have time to dance. He can play football — he’s in the school team, and
he can play tennis, and _
Woman 2: Susie can’t play football — she doesn’t like it.
It’s not a nice game for a girl. But she can play tennis, and she can ski, of course. Tell me, can Jonny ski?
Woman 1: No, but… he can speak French, you know…
Woman 2: Oh, of course Susie can speak French, and she can speak Spanish too,
and she can
Woman 1: Jonny can ride a bike and he …
Woman 2: Susie can’t ride a bike but she can drive a car.
Can Jonny drive?
Woman 1: Of course he can’t drive. He’s only ten!

Development of Radio
Technology

Who gave a demonstration (1895) of
the wireless telegraph?
Marconi succeeded in sending the
letter S across the Atlantic Ocean using Morse code, isn’t it?
Radio is based on the studies of
James Clerk Maxwell, who developed the mathematical theory of electromagnetic
waves, and Heinrich Hertz, who devised an apparatus for generating and
detecting them. Guglielmo Marconi, recognizing the possibility of using these
waves for a wireless communication system, gave a demonstration (1895) of the
wireless telegraph, using Hertz's spark coil as a transmitter and Edouard Branly's
coherer (a radio detector in which the conductance between two conductors is
improved by the passage of a high-frequency current) as the first radio
receiver. The effective operating distance of this system increased as the
equipment was improved, and in 1901, Marconi succeeded in sending the letter S
across the Atlantic Ocean using Morse code. In 1904, Sir John A. Fleming
developed the first vacuum electron tube , which was able to detect radio waves
electronically. Two years later, Lee de Forest invented the audion, a type of
triode, or three-element tube, which not only detected radio waves but also
amplified them.
Independent
work.  Work in pairs
Radio
telephony—the transmission of music and speech—also began in 1906 with the work
of Reginald Fessiden and Ernst F. W. Alexanderson, but it was not until Edwin
H. Armstrong patented (1913) the circuit for the regenerative receiver that
long-range radio reception became practicable. The major developments in radio
initially were for ship-to-shore communications. Radios that combine
transmitters and receivers are now widely used for communications. Police and
military forces and various businesses commonly use such radios to maintain
contact with dispersed individuals or groups. Citizens band (CB) radios,
two-way radios operating at frequencies near 27 megahertz, most typically used
in vehicles for communication while traveling, became popular in the 1970s.
Cellular telephones, despite the name, are another popular form of radio used
for communication.
A radio communication system
send signals by radio. –
 Types of radio communication systems
deployed depend on technology, standards, regulations, radio spectrum
allocation, user
requirements, service
positioning, and investment.
The radio equipment involved in
communication systems includes a transmitter and a receiver, each having an antenna and appropriate terminal
equipment such as a microphone at the transmitter and a loudspeaker at the
recieiver in the case of a voice-communication system.

«Invention of the
first Radio»
            May 7 is celebrated in
our country as Radio’s Day, in commemoration of the discovery made by the
Russian scientist Alexander Popov. On this day in 1895, Popov gave a working
demonstration of the first radio receiver in the world, and several months
later he transmitted the first radio message over a distance of 250
 metres.
We know Soviet television to have
developed swiftly in the past years and televiewing to have become one of the
favourite pastimes of our people.
In 1961 Soviet television appeared on
the international screen. More than 100 million people in 14 countrioes of
Europe were able to enjoy Soviet TV programmes. In their turn Soviet people saw
programmes from London ; Paris; Warsaw; Prague and other European cities.
Radio-engineering, electronics and
television are finding increasing application in the national economy,
transport and medicine.
The automation of industrial
processes, of heat and power stations,remote control and management, the
development of electronic computers and cybernetic systems—all this is possible
because of the achievements of electronics.A television system at the
Magnitogorsk Iron and Steel Mills helps to regulate the charging of the
furnaces, the vacuum pouring of steel and other operations TV at sea and river
ports makes possible the remote control and management of loading. With
underwater television it is possible to check on the submerged part of a ship’s
hull, to inspect sunkenships, and to study the sea and river bottom at varving
depths, the conditionof sluices, while with television sets of special design
it is possible to supervise the operation of bore holes and oil wells.
We know the organization of radio
communication with the first Soviet cosmonauts to have been a triumph of Soviet
radio-engineering. Now that the flights of the first cosmonauts are over, we
know the radio electronic equipment to have operated faultlessly. This was the
first two-way radio contact between man in outer space and the Earth.
During the space flights television
enabled doctors on the Earth to follow the state of health of the cosmonauts,
their movements and actions.
The development of Soviet science and
technology in the field of space research sets more complicated tasks to be
carried out by our radio-engineering and electronics experts.
One of the practical tasks of
radio-engineering in outer space is to use artificial satellites for the needs
of man on Earth. They ensure the transmission of meterological data collected
by instruments carried by artificial satellites. The sputniks are also for
international radio communication, broadcasting and world-wide television
systems.

Topical Vocabulary:
Gave a working demonstration---
практикалық көрсету
Transmitted the first radio message
ол бірінші таратуын жүзеге асырылады
Remote control and management—          қашықтан басқару пульті
Two-way radio contact—
                           екі-жақты радиобайланыс
Independent work. Answer the following questions:
1.Why was May 7 marked in our country
as Radio Day?
2. When did Soviet television appear
on the international screen?
3. How is electronics applied in the
national economy?
4  How could doctors on the Earth
follow the state of health of the cosmonaut during his flight?
5. How did the radio electronic
equipment operate during the flights of the Soviet cosmonauts?
6. What device makes remote control
possible
7. What practical tasks are carried
out by our radio-engineering and electronics experts?

Radio Transmitters.
A "transmitter" is an electronic device which, usually with the
aid of an antenna, propagates an electromagnetic signal such as radio,
television, or other telecommunications.

Principles of radio
     One of many applications of
electricity is the generation of invisible waves of energy called radio waves.
    With Oersted's accidental
discovery of electromagnetism, it was realized that electricity and magnetism
were related to each other. When an electric current was passed through a
conductor, a magnetic field was generated perpendicular to the axis of flow.
Likewise, if a conductor was exposed to a change in magnetic flux perpendicular
to the conductor, a voltage was produced along the length of that conductor. So
far, scientists knew that electricity and magnetism always seemed to affect
each other at right angles.
Scottish physicist James Clerk
Maxwell (1831-1879) "unified" the study of electricity and magnetism
in four relatively tidy equations. He discovered that electric and magnetic
fields were related to one another, with or without the presence of a
conductive path for electrons to flow. Maxwell's discovery was this:
A changing electric field
produces a perpendicular magnetic field, and A changing magnetic field produces
a perpendicular electric field.
    All of this can take place in
open space, the alternating electric and magnetic fields supporting each other
as they travel through space at the speed of light. This dynamic structure of
electric and magnetic fields propagating through space is better known as an
electromagnetic wave.
    There are many kinds of natural
radiative energy composed of electromagnetic waves. Even light is
electromagnetic in nature. So are X-rays and "gamma" ray radiation.
The only difference between these kinds of electromagnetic radiation is the
frequency of their oscillation (alternation of the electric and magnetic fields
back and forth in polarity). Byk using a source of AC voltage and a
special device called an antenna, we can create electromagnetic waves (of a
much lower frequency than that of light) with ease.
    An antenna is nothing more than a
device built to produce a dispersing electric or magnetic field. Two
fundamental types of antennae are the dipole and the loop.

        The dipole looks like an open
circuit, and the loop like a short circuit. These pieces of wire are effective
radiators of electromagnetic fields when connected to AC sources of high
frequency. The two open wires of the dipole act as a sort of capacitor (two
conductors separated by a dielectric), with the electric field open to
dispersal instead of being concentrated between two closely-spaced plates. The
closed wire path of the loop antenna acts like an inductor with a large air
core, again providing opportunity for the field to disperse away from the
antenna instead of being concentrated and contained as in a normal inductor.
        As the powered dipole
radiates its changing electric field into space, a changing magnetic field is
produced at right angles, thus sustaining the electric field further into
space, and so on as the wave propagates at the speed of light. As the powered
loop antenna radiates its changing magnetic field into space, a changing
electric field is produced at right angles, with the same end-result of a
continuous electromagnetic wave sent away from the antenna. Both types antennas
achieves the same basic task: the controlled production of an electromagnetic
field.
         When attached to a source of
high-frequency AC power, an antenna acts as a transmitting device, converting
AC voltage and current into electromagnetic wave energy. Antennas also have the
ability to intercept electromagnetic waves and convert their energy into AC
voltage and current. In this mode, an antenna acts as a receiving device.

Radio receivers
A
"radio receiver" is an electronic circuit that receives its input from an antenna, uses electronic filters to separate a wanted radio signal
from all other signals picked up by this antenna, amplifies it to a level suitable for further processing, and finally
converts through demodulation and decoding the signal into a form usable for
the consumer, such as sound, pictures, digital data, measurement values,
navigational positions, etc. [http://www.radio-electronics.com/info/receivers/index.php
Radio-Electronics, "Radio Receiver Technology"]
The crystal radio receiver is a very
simple kind of radio receiver. It needs no battery or power source except the
power received from radio waves by a long outdoor wire antenna.
Portable radios include simple transistor radios that are
typically monoaural and receive the AM, FM, and/or short wave broadcast bands.
FM, and often AM, radios are sometimes included as a feature of portable CD,
MP3 CD, and USB key players, as well as cassette player/recorders.
Self-powered portable radios, such as clockwork radios are
used in developing nations or as part of an emergency preparedness kit. [http://radio.electrical-guide.info/types/
The Radio Guide, "Types of Portable Radios"]
A communications receiver is a type of radio receiver used
as a component of radio communication link. Commercial communications receivers
are characterised by high stability and reliability of performance, and are
generally adapted for remote control and monitoring.

Glossary of electronic terms and Abbreviations
A - Abbreviation for
"ampere" a unit of electrical current.
absorption - Loss
or dissipation of energy as it travels through a medium, Example: radio waves
lose some of their energy as they travel through the atmosphere.
AC - Abbreviation for
"Alternating Current"
acceptor atoms -
Trivalent atoms that accept free electrons from pentavalent atoms.
AC coupling -
Circuit that passes an AC signal while blocking a DC voltage.
AC/DC -
Equipment that will operate on either an AC or DC power source.
AC generator -
Device used to transform mechanical energy into AC electrical power.
AC load line - A
graph representing all possible combinations of AC output voltage and current
for an amplifier.
AC power supply - Power
supply that delivers an AC voltage.
active component - A
component that changes the amplitude of a signal between input and output.
active filter - A
filter that uses an amplifier in addition to reactive components to pass or
reject selected frequencies.
active region - The
region of BJT operation between saturation and cutoff used for linear
amplification.
AC voltage - A
voltage in which the polarity alternates.
ADC - Abbreviation for
"analog to digital converter"
Admittance -
(symbol "Y") Measure of how easily AC will flow through a circuit.
Admittance is the reciprocal of impedance and is measured in siemens.
AF - Abbreviation for
"audio frequency".
AFC - Abbreviation for
"automatic frequency control".
AGC - Abbreviation for
"automatic gain control"
alkaline cell - A
primary cell that delivers more current than a carbon-zinc cell. Also known as
an "alkaline manganese cell".
alligator clip -
Spring clip on the end of a test lead used to make a temporary connection.
alpha - Ratio
of collector current to emitter current in a bipolar junction transistor (BJT).
Greek letter alpha "" is the symbol used.
alternating current -
An electric current that rises to a maximum in one direction, falls back to
zero and then rises to a maximum in the opposite direction and then repeats.
alternator - Name
for an AC generator.
AM - Abbreviation for
"amplitude modulation"
ammeter - A
meter used to measure current.
ampere - Unit
of electrical current.
amplifier - A
circuit that increases the voltage, current, or power of a signal.
amplitude -
Magnitude or size of a signal voltage or current.
analog -
Information represented as continuously varying voltage or current rather than
in discrete levels as opposed to digital data varying between two discrete
levels.
anode - The
positive electrode or terminal of a device. The "P" material of a
diode.
antenna, transmitting -
A device that converts an electrical wave into an electromagnetic wave that radiates
away from the antenna.
antenna, receiving -
A device that converts a radiated electromagnetic wave into an electrical wave.
apparent power - Power
attained in an AC circuit as a product of effective voltage and current which
reach their peak at different times.
arc - Discharge of
electricity through a gas such as lightning discharging through the atmosphere.
armature - The
rotating or moving component of a magnetic circuit.
armstrong oscillator -
An oscillator that uses an isolation transformer to achieve positive feedback
from output to input.
astable multivibrator -
An oscillator that produces a square wave output from a DC voltage.
atom - The
smallest particle that an element can be broken down into and still maintain
its unique identity.
atomic number - The
number of positive charges or protons in the nucleus of an atom.
attenuate - To
reduce the amplitude of an action or signal. The opposite of amplification.
audio -
Relating to frequencies that can be heard by the human ear. Approximately 20 Hz.
to 20 kHz.
autotransformer - A
single winding transformer where the output is taken from taps on the winding.
average value - A
value of voltage or current where the area of the wave above the value equals
the area of the wave below the value.
AVC - Abbreviation for
"automatic volume control"
avionics -
Aviation electronics.
AWG - Abbreviation for
"American wire gauge". A gauge that assigns a number value to the
diameter of a wire.
balanced bridge - Condition that occurs when
a bridge circuit is adjusted to produce a zero output.
band-pass filter - A
tuned circuit designed to pass a band of frequencies between a lower cut-off
frequency (f1) and a higher cut-off frequency (f2).
Frequencies above and below the pass band are heavily attenuated.
band-stop filter - A
tuned circuit designed to stop frequencies between a lower cut-off frequency (f1)
and a higher cut-off frequency (f2) of the amplifier while passing
all other frequencies.
bandwidth - Width
of the band of frequencies between the half power points.
barrier potential -
The natural difference of potential that exists across a forward biased pn
junction.
base - The
region that lies between the emitter and collector of a bipolar junction
transistor (BJT).
base biasing - A
method of biasing a BJT in which the bias voltage is supplied to the base by
means of a resistor.
battery - A DC
voltage source containing two or more cells that convert chemical energy to
electrical energy.
baud - A
unit of signaling speed equal to the number of signal events per second. Not
necessarily the same as bits per second.
beta - (b)
The ratio of collector current to base current in a bipolar junction transistor
(BJT).
bias - A DC
voltage applied to a device to control its operation.
binary - A
number system having only two symbols, 0 and 1. A base 2 number system.
bipolar junction transistor - (BJT), A three terminal device in which emitter to
collector current is controlled by base current.
bistable multivibrator - A multivibrator with two stable states. An external signal
is required to change the output from one state to the other. Also called a
latch.
bleeder current - A
current drawn continuously from a source. Bleeder current is used to stabilize
the output voltage of a source.
bode plot - A
graph of gain versus frequency.
branch current - The
portion of total current flowing in one path of a parallel circuit.
breakdown voltage -
Voltage at which the breakdown of a dielectric or insulator occurs.
break over voltage -
Minimum voltage required to cause a diac to break down and conduct.
bridge rectifier - A
circuit using four diodes to provide full wave rectification. Converts an AC
voltage to a pulsating DC voltage.
buffer - An
amplifier used to isolate a load from a source.
bulk resistance - The
natural resistance of a "P" type or "N" type semiconductor
material.
Butterworth filter -
A type of active filter characterized by a constant gain (flat response) across
the mid-band of the circuit and a 20 dB per decade roll-off rate for each pole
contained in the circuit.
BW - Abbreviation for
bandwidth.
bypass capacitor - A
capacitor used to provide an AC ground at some point in a circuit.
byte - Group
of eight binary digits or bits.
cable - Group of two or more
insulated wires.
CAD - Abbreviation for
"computer aided design"
calibration - To
adjust the correct value of a reading by comparison to a standard.
capacitance - The
ability of a capacitor to store an electrical charge. The basic unit of
capacitance is the Farad.
capacitive reactance -
The opposition to current flow provided by a capacitor. Capacitive reactance is
measured in ohms and varies inversely with frequency.
capacitor - An
electronic component having capacitive reactance.
capacitor microphone -
Microphone whose operation depends on variations in capacitance caused by
varying air pressure on the movable plate of a capacitor.
carbon-film resistor -
Device made by depositing a thin carbon film on a ceramic form.
carbon microphone -
Microphone whose operation depends on pressure variation in carbon granules
causing a change in resistance.
carbon resistor -
Resistor of fixed value made by mixing carbon granules with a binder which is
moulded and then baked.
cascaded amplifier -
An amplifier with two or more stages arranged in a series configuration.
cascode amplifier -
A high frequency amplifier made up of a common-source amplifier with a
common-gate amplifier in its drain network.
cathode - The
negative terminal electrode of a device. The "N" material in a
junction diode.
cathode ray tube - (CRT)
Vacuum tube used to display data in a visual form. Picture tube of a television
or computer terminal.
cell -
Single unit used to convert chemical energy into a DC electrical voltage.
center frequency -
Frequency to which an amplifier is tuned. The frequency half way between the
cut-off frequencies of a tuned circuit.
center tap -
Midway connection between the two ends of a winding.
center tapped rectifier - Circuit that make use of a center tapped transformer and
two diodes to provide full wave rectification.
center tapped transformer - A transformer with a connection at the electrical center
of a winding.
ceramic capacitor -
Capacitor in which the dielectric is ceramic.
charge -
Quantity of electrical energy.
charge current -
Current that flows to charge a capacitor or battery when voltage is applied.
chassis - Metal
box or frame into which components are mounted.
chassis ground -
Connection to a chassis.
chebyshev filter - A
type of active filter characterized by high roll-off rates (40 dB per decade
per pole) and mid-band gain that is not constant.
choke -
Inductor used to oppose the flow of alternating current.
circuit -
Interconnection of components to provide an electrical path between two or more
components.
circuit breaker - A
protective device used to open a circuit when current exceeds a maximum value.
In effect a reusable fuse.
clamper - A
diode circuit used to change the DC level of a waveform without distorting the
waveform.
clapp oscillator - A
variation of the Colpitts oscillator. An added capacitor is used to eliminate
the effects of stray capacitance on the operation of the basic Colpitts
oscillator.
class A amplifier -
A linear amplifier biased so the active device conducts through 360 degrees of
the input waveform.
class B amplifier -
An amplifier with two active devices. The active components are biased so that
each conducts for approximately 180 degrees of the input waveform cycle.
class C amplifier -
An amplifier in which the active device conducts for less than 180 degrees of
the input waveform cycle.
clipper - A
diode circuit used to eliminate part of a waveform
clipping -
Distortion caused by overdriving an amplifier.
clock - A
square waveform used for synchronizing and timing of several circuits.
closed circuit -
Circuit having a complete path for current flow.
closed-loop gain - Gain
of an amplifier when a feedback path is present.
coaxial cable -
Transmission line in which the signal carrying conductor is covered by a
dialectric and another conductor.
coefficient of coupling - The degree of coupling between two circuits.
coercive force - (H)
Magnetizing force needed to reduce residual magnetism in a material to zero.
collector - The
semiconductor region in a bipolar junction transistor through which a flow of
charge carriers leaves the base region.
collector characteristic curve - A graph of collector voltage over collector current for a
given base current.
color code - Set
of colors used to indicate value of a component.
colpitts oscillator -
An oscillator with a pair of tapped capacitors in the feedback network.
common-anode display -
A multi-segment light emitting diode (LED) with a single positive voltage input
connection. Separate cathode connections are provided for each individual
segment.
common cathode display - A multi-segment light emitting diode (LED) with a single
negative voltage input connection. Separate anode connections are provided for
each individual segment.
common base amplifier -
A BJT circuit in which the base connection is common to both input and output.
common collector amplifier - A BJT circuit in which the collector connection is common
to both input and output.
common drain amplifier - A FET circuit in which the drain connection is common to
both input and output.
common emitter amplifier - A BJT circuit in which the emitter connection is common to
both input and output.
common gate amplifier -
A FET circuit in which the gate connection is common to both input and output.
common source amplifier - A FET circuit in which the source connection is common to
both input and output.
common-mode rejection ratio - (CMRR) The ratio of op-amp differential gain to
common-mode gain. A measure of an op-amp's ability to reject common-mode
signals such as noise.
common-mode signals -
Signals that appear simultaneously at two inputs of an operational amplifier
(op-amp). Common mode signals are always equal in amplitude and phase.
comparator - An
op-amp circuit that compares two inputs and provides a DC output indicating the
polarity relationship between the inputs.
complementary symmetry amplifier - A class B amplifier using matched complementary
transistors. Does not require a phase inverter for push-pull output.
complementary transistors - Two transistors, one NPN and one PNP having near identical
characteristics. N-channel and P-channel FETs can also be complementary.
complex numbers -
Numbers composed of a real number part and an imaginary number part.
compliance - The
maximum possible peak-to-peak output of an amplifier.
constant current circuit - Circuit used to maintain constant current to a load having
resistance that changes.
contact -
Current carrying part of a switch, relay or connector.
continuity -
Occurs when a complete path for current exists.
conventional current flow - Concept of current produced by the movement of positive
charges towards the negative terminal of a source.
copper loss - Power
lost in transformers, generators, connecting wires and other parts of a circuit
due to current flow through the resistance of copper conductors.
core -
Magnetic material within a coil used to concentrate the magnetic field.
coulomb - Unit
of electric charge. A negative coulomb charge consists of 6.24 × 1018 electrons.
counter electromotive force - (counter emf) Voltage induced into an inductor due to an
alternating or pulsating current. Counter emf is always in polarity opposite to
that of the applied voltage. Opposing a change of current.
coupling - To
electronically connect two circuits so that signal will pass from one to the
other.
covalent bond - The
way some atoms complete their valence shells by sharing valence electrons with
neighbouring atoms.
crossover distortion -
Distortion caused by both devices in a class B amplifier being cut-off at the
same time.
crowbar -
Circuit used to protect the output of a source from a short circuited load.
Load current is limited to a value the source can deliver without damage.
CRT - Abbreviation for
cathode ray tube.
crystal -
Natural or synthetic piezoelectric or semiconductor material with atoms
arranged with some degree of geometric regularity.
crystal-controlled oscillator - Oscillator that uses a quartz crystal in its feedback path
to maintain a stable output frequency.
current -
Measured in amperes, it is the flow of electrons through a conductor. Also know
as electron flow.
current amplifier -
Amplifier to increase signal current.
current divider -
Parallel network designed to divide the total current of a circuit
current feedback -
Feedback configuration where a portion of the output current is fed back to the
amplifier input.
current-limiting resistor - Resistor in the path of current flow to control the amount
of current drawn by a device.
current mirror - Term
used to describe the fact that DC current through the base circuit of a class B
amplifier is approximately equal to the DC collector current.
cutoff -
Condition when an active device is biased such that output current is near zero
or beyond zero.
cutoff frequency -
Frequency at which the power gain of an amplifier falls below 50% of maximum.
cycle - When
a repeating wave rises from zero to a positive maximum then back to zero and on
to a negative maximum and back to zero it is said to have completed one cycle.
DAC - Abbreviation for
"digital to analog converter."
damping - Reduction
in magnitude of oscillation due to energy being dissipated as heat.
Darlington pair - An
amplifier consisting of two bipolar junction transistors with their collectors
connected together and the emitter of one connected to the base of the other.
Circuit has an extremely high current gain and input impedance.
DC - Abbreviation for
"direct current".
DC load line - A
graph representing all possible combinations of voltage and current for a given
load resistor in an amplifier.
DC offset - The
change in input voltage required to produce a zero output voltage when no
signal is applied to an amplifier.
DC power supply - Any
source of DC power for electrical equipment.
dead short - Short
circuit having zero resistance.
decade - A
frequency factor of ten.
decibel - (dB)
a logarithmic representation of gain or loss.
degenerative feedback -
Also called negative feedback. A portion of the output of an amplifier is
inverted and connected back to the input. This controls the gain of the
amplifier and reduces distortion and noise.
delay time - The
time for collector current to reach 10% of its maximum value in a BJT switching
circuit.
depletion region - The
area surrounding a pn junction that is depleted of carriers.
depletion mode - In a
FET, an operating mode where reverse gate-source voltage is used to deplete the
channel of free carriers. This reduces the size of the channel and increases
its resistance.
depletion-mode MOSFET -
A MOSFET designed to operate in either depletion mode or enhancement mode.
device - A
component or part.
diac - A two
terminal bidirectional thyristor. Has a symmetrical switching mode.
dielectric -
Insulating material between two plates where an electrostatic field exists.
dielectric constant -
Property of a material that determines how much electrostatic energy can be
stored per unit volume when unit voltage is applied.
dielectric strength -
The maximum voltage an insulating material can withstand without breaking down.
differential amplifier - An amplifier in which the output is in proportion to the
differences between voltages applied to its two inputs.
differentiator - A
circuit in which the output voltage is in proportion to the rate of change of
the input voltage. A high pass RC circuit.
diffusion -
Tendency of conduction band electrons to wander across a pn junction to combine
with valence band holes.
digital -
Relating to devices or circuits that have outputs of only two discrete levels.
Examples: 0 or 1, high or low, on or off, true or false etc.
diode - A two
terminal device that conducts in only one direction.
DIP - Abbreviation for
"dual in line package."
direct coupling - Where
the output of an amplifier is connected directly to the input of another
amplifier or to a load. Also known as DC coupling because DC signals are not
blocked.
direct current -
Current that flows in only one direction.
discharge -
Release of energy stored in either a battery or a capacitor.
discrete component -
Package containing only a single component as opposed to an integrated circuit
containing many components in a single package.
dissipation - Release
of electrical energy in the form of heat.
distortion - An
undesired change in a waveform or signal.
distributed capacitance - Any capacitance other than that within a capacitor. For
example, the capacitance between adjacent turns of wire in a coil.
distributed inductance - Any inductance other than that within an inductor. Example
inductance in any conductor.
domain - A
moveable magnetized area in a magnetized material. Also known as magnetic
domain.
donor atoms -
Pentavalent atoms that give up electrons to the conduction band in an N type
semiconductor material.
doping - The
process of adding impurity atoms to intrinsic (pure) silicon or germanium to
improve the conductivity of the semiconductor material.
dot convention -
Standard used with transformer symbols to indicate whether the secondary
voltage is in phase or out of phase with the primary voltage.
drift - A
problem that can develop in tuned amplifiers when the frequency of the tuned
circuit changes due to temperature or component aging.
dropping resistor -
Resistor whose value has been chosen to drop or develop a given voltage.
dry cell - DC
voltage generating chemical cell using a non liquid (paste) electrolyte.
dual in-line package -
Integrated circuit package having two rows of connecting pins.
dual trace oscilloscope - Oscilloscope that can simultaneously display two signals.
dynamic -
Relating to conditions that are changing or in motion.
E-core - Laminated form in the shape
of the letter "E", onto which inductors and transformers are wound.
eddy currents -
Currents induced into a conducting core due to the changing magnetic field.
Eddy currents produce heat which is a loss of power and lowers the efficiency
of an inductor.
efficiency - The
amount of power delivered to the load of an amplifier as a percentage of the
power required from the power supply.
electric charge -
Electric energy stored on the surface of a material. Also known as a static
charge.
electric field - A
field or force that exists in the space between two different potentials or
voltages. Also known as an electrostatic field.
electricity -
Science states that certain particles possess a force field or charge. The
charge possessed by an electron is negative while the charge possessed by a
proton is positive. Electricity can be divided into two groups, static and
dynamic. Static electricity deals with charges at rest and dynamic electricity
deals with charges in motion.
electric polarization -
A displacement of bound charges in a dielectric when placed in an electric
field.
electro acoustic transducer - Device that produces an energy transfer from electric to
acoustic (sound) or from acoustic to electric. Examples include a microphone,
earphones and loudspeakers.
electroluminescence -
Conversion of electrical energy into light energy.
electrolyte -
Electrically conducting liquid (wet) or paste (dry)
electrolytic capacitor - A capacitor having an electrolyte between the two plates.
A thin layer of oxide is deposited on only the positive plate. The oxide acts
as the dielectric for the capacitor. Electrolytic capacitors are polarized and
so must be connected in correct polarity to prevent breakdown.
electromagnet - A
coil of wire usually wound on a soft iron or steel core. When current is passed
through the coil a magnetic field is generated. The core provides an easy path
for the magnetic lines of force. This concentrates the field in the core.
electromagnetic communication - Use of an electromagnetic wave to pass information between
two points. Also called wireless communication.
electromagnetic induction - Voltage produced in a coil due to relative motion between
the coil and magnetic lines of force.
electromagnetic spectrum - List or diagram showing the range of electromagnetic
radiation.
electromagnetic wave -
Wave that consists of both electric and magnetic variation.
electromagnetism -Relates
to the magnetic field generated around a conductor when current is passed
through it.
electromechanical transducer - Device that transforms electrical energy into mechanical
energy (electric motor) or mechanical energy into electrical energy
(generator).
electromotive force -
(emf) Force that causes the motion of electrons due to potential difference
between two points. (voltage)
electron -
Smallest sub atomic particle of negative charge that orbits the nucleus of an
atom.
electron flow -Electrical
current produced by the movement of free electrons towards a positive terminal.
electrostatic -
Related to static electric charge.
electrostatic field -
Force field produced by static electrical charges.
emitter - The
semiconductor region from which charge carriers are injected into the base of a
bipolar junction transistor.
emitter feedback -
Coupling from the emitter output to the base input of a bipolar junction
transistor.
emitter follower - A
common collector amplifier. Has a high current gain, high input impedance and
low output impedance.
energized - Being
electrically connected to a voltage source so the device is activated.
energy -
Capacity to do work.
engineering notation -
A floating point system in which numbers are expressed as products consisting
of a number greater than one multiplied by an appropriate power of ten that is
some multiple of three.
enhancement-mode MOSFET - A field effect transistor in which there are no charge carriers
in the channel when the gate source voltage is zero.
equivalent resistance -
Total resistance of all the individual resistances in a circuit.
fall time - Time it takes the falling
edge of a pulse to go from 90% of peak voltage to 10% of peak voltage.
farad - The
basic unit of capacitance.
feedback - A
portion of the output signal of an amplifier which is connected back to the
input of the same amplifier.
feedback amplifier -
An amplifier with an external signal path from its output back to its input.
ferrite - A
powdered, compressed and sintered magnetic material having high resistively.
The high resistance makes eddy current losses low at high frequencies.
ferrite bead -
Ferrite composition in the form of a bead. Running a wire through the bead
increases the inductance of the wire.
ferrite-core inductor -
An inductor wound on a ferrite core.
ferrites -
Compound composed of iron oxide, a metallic oxide and ceramic. The metal oxides
include zinc, nickel, cobalt or iron.
ferrous -
Composed of and or containing iron. A ferrous metal exhibits magnetic
characteristics as opposed to non-ferrous material.
fiber optics -
Laser's light output carries information that is conveyed between two points by
thin glass optical fibers.
field effect transistor - (FET) A voltage controlled transistor in which the source
to drain conduction is controlled by gate to source voltage.
filament - Thin
thread of carbon or tungsten which produces heat or light with the passage of
current.
filter -
Network consisting of capacitors, resistors and/or inductors used to pass
certain frequencies and block others.
flip flop - A
bistable multivibrator. A circuit which has two output states and is switched
from one to the other by means of an external signal (trigger).
floating ground -
Common connection in a circuit that provides a return path for current but is
not connected to an earth ground.
flow soldering - Flow
or wave soldering technique in large scale electronic assembly to solder all
the connections on a printed circuit board by moving the board over a wave of
molten solder.
flux -
Material used to remove oxide films from the surface of metals in preparation
for soldering.
flux - In
magnetism, the magnetic field consisting of lines of force.
flux density - The
concentration of magnetic lines of force. Determines strength of the magnetic
field.
flywheel effect -
Sustaining effect of oscillation in an LC circuit.
forward bias - A PN
junction bias which allows current to flow through the junction. Forward bias
decreases the resistance of the depletion layer.
free electrons -
Electrons that are not in any orbit around a nucleus.
free running multivibrator - A multivibrator that produces a continuous output waveform
without any signal input. A square wave generator used to produce a clock
signal.
frequency - Rate
of recurrence of a periodic wave. Measured in Hertz (cycles per second).
frequency-division multiplex - (FDM) Transmission of two or more signals over a common
path by using a different frequency band for each signal.
frequency-domain analysis - A method of representing a waveform by plotting its
amplitude against frequency.
frequency meter - Meter
used to measure frequency of periodic waves.
frequency multiplier -
A harmonic conversion circuit in which the frequency of the output signal is an
exact multiple of the input frequency.
frequency response -
Indication of how well a circuit responds to different frequencies applied to
it.
frequency response curve - A graph of amplitude over frequency indicating a circuit response
to different frequencies.
full scale deflection -
(FDS) Deflection of a meter's pointer to the farthest position on the scale.
full wave rectifier -
Rectifier that makes use of the full AC wave in both the positive and negative
half cycles.
function generator -
Signal generator that can produce sine, square, triangle and saw tooth output
waveforms.
fundamental frequency -
Lowest frequency in a complex waveform.
fuse - A
protective device in the current path that melts or breaks when current exceeds
a predetermined maximum value.
gain - Increase in voltage,
current and/or power. Gain is expressed as a ratio of amplifier output value to
the corresponding amplifier input value.
gain bandwidth product - A device parameter that indicates the maximum possible
product of gain and bandwidth. The gain bandwidth product of a device is equal
to the unity gain frequency (funity) of the device.
gamma rays - High
frequency electromagnetic radiation from radio active particles.
ganged -
Mechanical coupling of two or more capacitors, switches, potentiometers, or any
other adjustable components so that adjusting one control will operate all.
gas - Any aeriform or
completely elastic fluid which is not a solid or a liquid. Gasses are produced
by heating a liquid beyond its boiling point.
geiger counter -
Device used to detect nuclear particles.
generator -
Device used to convert mechanical energy to electrical energy.
giga -
Metric prefix for 1 billion (109).
ground - An
intentional or accidental conducting path between an electrical system or
circuit and the earth or some conducting body acting in place of the earth. A
ground is often used as the common wiring point or reference in a circuit.
gunn diode - A
semiconductor diode that utilizes the Gunn effect to produce microwave
frequency oscillation or to amplify a microwave frequency signal.
half power point - A frequency at which the
power is 50% of maximum. This corresponds to 70.7% of maximum current or
voltage.
h-parameters -
(hybrid parameters) Transistor specifications that describe the component
operating limits under specific circumstances.
half wave rectifier -
A diode rectifier that converts AC to pulsating DC by eliminating either the
negative or the positive alternation of each input AC cycle.
harmonic - Sine
wave that is smaller in amplitude and some multiple of a fundamental frequency.
Example: 880 Hz. is the second harmonic of 440 Hz., 880 Hz. is the third
harmonic of 220 Hz.
hartley oscillator -
An oscillator that uses a tapped inductor in the feedback network.
henry - The
basic unit of inductance.
HERTZ - (Hz.)
Unit of frequency. One hertz is equal to one cycle per second.
high fidelity - (Hi
Fi)Sound reproduction equipment that reproduces sound as near to the original
sound as possible
high-pass filter - A
tuned circuit designed to pass all frequencies above a desnigated cut-off
frequency. Frequencies below the cut-off frequency are rejected or attenuated
high tension -
Lethal voltage in the kilovolt range and above.
hole - A gap
left in the covalent bond when a valence electron gains sufficient energy to
jump to the conduction band
hologram -
Three-dimensional picture created with a laser.
holography - The
science dealing with three-dimensional optical recording.
horizontally polarized wave - Electromagnetic wave that has the electric field in the
horizontal plane.
hybrid circuit -
Circuit that combines two technologies (passive and active or discrete and
integrated components) onto one microelectronic circuit. Passive components are
usual made by thin film techniques, while active components are made with
semiconductor techniques.
hysteresis -
Amount that the magnetization of a material lags the magnetizing force due to
molecular friction. In Schmitt Trigger circuits, the difference between the
upper and lower trigger points.
IC - Abbreviation for
"integrated circuit"
IC voltage regulator -
Three terminal device used to hold the output voltage of a power supply
constant over a wide range of load variations.
IGFET -
Insulated gate field effect transistor. Another name for a "MOSFET."
impedance - (Z)
Measured in ohms it is the total opposition to the flow of current offered by a
circuit. Impedance consists of the vector sum of resistance and reactance.
impedance coupling -
Coupling of two signal amplifier circuits through the use of an impedance such
as a inductor.
impedance matching -
Matching the output impedance of a source to the input impedance of a load to
attain maximum power transfer.
incandescence - State
of a material when heated to the point where it emits light. (red hot or white
hot).
induced voltage -
Voltage generated in a conductor when subjected to a moving magnetic field.
inductance -
Property of a circuit to oppose a change in current. The moving magnetic field
produced by a change in current causes an induced voltage to oppose the
original change.
inductive circuit -
Circuit having greater inductive reactance than capacitive reactance.
inductive reactance -
Opposition to the flow of AC current produced by an inductor. Measured in Ohms
and varies in direct proportion to frequency.
inductor -
Length of conductor used to introduce inductance into a circuit. The conductor
is usually wound into a coil to concentrate the magnetic lines of force and
maximize the inductance. While any conductor has inductance, in common usage
the term inductor usually refers to a coil.
infrared -
Electromagnetic heat radiation whose frequencies are above the microwave
frequency band and below red in the visible band.
inhibit - To
stop an action or block data from passing.
in phase - When
two or more waves of the same frequency have their positive and negative peaks
occurring at the same time.
input impedance -
Opposition to the flow of signal current at the input of a circuit or load.
insulated - When
a non conducting material is used to isolate conducting materials from one
another.
insulating material -
Material that will prevent the flow of current due to its chemical composition.
insulation resistance -
Resistance of insulating material. The greater the insulation resistance, the
better the insulation.
integrated - When
two or more components are combined into a circuit and then incorporated into a
single package.
integrator - A
device that approximates and whose output is proportional to an integral of the
input signal. A low pass filter.
intermediate frequency amplifier - In a super heterodyne radio it amplifies a fixed frequency
lower than the received radio frequency and higher than the audio frequency.
intermittent - A
fault occurring at random intervals of time. Intermittent problems are often
difficult to locate because of the random nature. They often don't occur when
the technician is present.
internal resistance -
Every source has some resistance in series with the output current. When
current is drawn from the source some power is lost due to the voltage drop
across the internal resistance. Usually called output impedance or output
resistance.
intrinsic material -
A semiconductor material with electrical properties essentially characteristic
of ideal pure crystal. Essentially silicon or germanium crystal with no
measurable impurities.
intrinsic stand-off ratio - A unijunction transistor (UJT) rating used to determine
the firing potential of the device.
inverting amplifier -
An amplifier that has a 180° phase shift from input to output.
inverting input - In an
operational amplifier (op amp) the input that is marked with a minus sign. A
signal applied at the inverting input will be given 180° phase shift between
input and output.
ion - An atom with
fewer electrons in orbit than the number of protons in the nucleus is a
positive ion. An atom with a greater number of electrons in orbit than the
number of protons in the nucleus is a negative ion.
ionized - Atoms
become ionized when they gain or lose a valence electron.
j - A prefix used to indicate
an imaginary number. (Operator j)
jack -
Socket or connector into which a plug may be inserted.
JFET -
Abbreviation for "Junction field effect transistor".
joule - The
unit of work and energy.
junction - Contact
or connection between two or more wires or cables. The area where the p-type
material and n-type material meet in a semiconductor.
junction diode -
diode. A semiconductor diode in which the rectifying characteristics occur at a
junction between the n-type and p-type semiconductor
materials.
kilo - Metric prefix for 1000. (103).
kilovolt-ampere - 1000
volts at 1 ampere.
kilowatt-hour - 1000
watts for 1 hour.
kilowatt-hour meter -
A meter used by electric utility companies to measure the amount of electric
power used by a customer.
kinetic energy -
Energy associated with motion.
Kirchhoff"s current law - The sum of the currents flowing into a point in a circuit
is equal to the sum of the currents flowing out of that same point.
Kirchhoff"s voltage law - The algebraic sum of the voltage drops in a closed path
circuit is equal to the algebraic sum of the source voltages applied.
knee voltage - The
voltage at which a curve joins two relatively straight portions of a
characteristic curve. For a PN junction diode, the point in the forward
operating region of the characteristic curve where conduction starts to
increase rapidly. For a zener diode, the term is often used in reference to the
zener voltage rating.
lag - Difference in time between
two waveforms of the same frequency expressed in degrees. Example: One waveform
lags another waveform by a certain number of degrees.
laminated core - Core
made up of sheets of magnetic material insulated from one another by an oxide
or varnish.
lamp -
Device that produces light.
laser -
Device that produces a very narrow intense beam of light. The name is an
axcronym for "light amplification by stimulated emission of radiation.
lead - The
angle by which one alternating signal leads another in time. Opposite of lag.
Also a wire that connects two points in a circuit.
lead-acid cell - Cell
made up of lead plates immersed in a sulphuric acid electrolyte. An automobile
battery usually consists of six lead-acid cells.
leakage - Small
undesirable flow of current through an insulator or dielectric.
LED - Abbreviation for
"light emitting diode."
left-hand-rule - If
fingers of the left hand are placed around a wire so that the thumb points in
the direction of electron flow, the fingers will be pointing in the direction
of the magnetic field being produced by the conductor.
Lenz's law - The
current induced in a circuit due to a change in the magnetic field is so
directed as to oppose the flux, or to exert a mechanical force to oppose the
motion.
level detector - An
op-amp circuit that compares two inputs and provides a DC output indicating the
polarity relationship between the inputs. A comparator.
lie detector - Piece
of electronic equipment also called a polygraph used to determine whether a
person is telling the truth by looking for dramatic changes in blood pressure,
body temperature, breathing rate, heart rate and skin moisture in response to
questions.
light -
Electromagnetic radiation in a band of frequencies that can be received by the
human eye.
lifetime - The
time from the creation of an electron hole pair until recombination occurs.
light-emitting diode -
A semiconductor diode that converts electric energy into electromagnetic
radiation at a visible and near infrared frequencies when its pn junction
is forward biased.
limiter -
Circuit or device that prevents some portion of its input from reaching the
output. A clipper.
linear -
Relationship between input and output in which the output varies in direct
proportion to the input.
linear scale - A
scale in which the divisions are uniformly spaced.
line regulation - The
ability of a voltage regulator to maintain a constant voltage when the
regulator input voltage varies.
live - Term
used to describe a circuit or piece of equipment that is on and has current
flow within it.
load - A
source drives a load. Whatever component or piece of equipment is connected to
a source and draws current from a source is a load on that source.
load current -
Current drawn from a source by a load.
load impedance -
Vector sum of reactance and resistance in a load.
loading effect - Large
load impedance will draw a small load current and so loading of the source is
small. (light load). A small load impedance will draw a large load current from
the source. (heavy load).
load regulation - The ability
of a voltage regulator to maintain a constant output voltage under varying load
currents.
load resistance -
Resistance of a load.
logic -
Science of dealing with the principle and applications of gates, relays and
switches.
loss - Term
used to describe a decrease in power.
low pass filter - A
tuned circuit designed to pass all frequencies below a designated cut-off
frequency.
magnet - Body that can be used to
attract or repel magnetic materials.
magnetic circuit breaker - Circuit breaker that is tripped or activated by use of an
electromagnet.
magnetic coil -
Spiral of a conductor which is called an electromagnet.
magnetic core -
Material that exists in the center of the magnetic coil to either physically
support the windings (non-magnetic material) or to concentrate the magnetic
flux (magnetic material).
magnetic field -
Magnetic lines of force traveling from the north pole to the south pole of a
magnet.
magnetic flux - The
magnetic lines of force produced by a magnet.
magnetic leakage - The
passage of magnetic flux outside the path along which it can do useful work.
magnetic poles -
Points of a magnet from which magnetic lines of force leave (north pole) and
arrive (south pole).
magnetism -
Property of some materials to attract or repel others.
magnetizing force -
Also called magnetic field strength. It is the magneto motive force per unit
length at any given point in a magnetic circuit.
magneto motive force -
Force that produces a magnetic field.
majority carriers -
The conduction band electrons in an n-type material and the valence band holes
in a p-type material. Produced by pentavalent impurities in n-type material and
trivalent impurities in p-type material.
matched impedance -
Condition that occurs when the output impedance of a source is equal to the
input impedance of a load.
matching -
Connection of two components or circuits so that maximum power is transferred
between the two.
maximum power transfer - A theorem that states that maximum power will be
transferred from source to load when input impedance of the load equals the
output impedance of the source.
Maxwell - Unit
of magnetic flux. One maxwell equals one magnetic line of force.
mercury cell -
Primary cell using a mercuric oxide cathode, a zinc anode and a potassium
hydroxide electrolyte.
metal film resistor -
A resistor in which a film of metal oxide or alloy is deposited on an
insulating substrate.
metal oxide field effect transistor - (MOSFET) A field effect transistor in which the insulating
layer between the gate electrode and the channel is a metal oxide layer.
metal oxide resistor -
A metal film resistor in which an oxide of metal (such as tin) is deposited as
a film onto the substrate.
meter - Any
electrical or electronic measuring device. In the metric system, it is the unit
of length equal to 39.37 inches.
meter FSD current -
Value of meter current needed to cause the needle to deflect to its maximum
position (full scale deflection).
meter resistance - DC
resistance of the meter's armature coil.
mica capacitor -
Capacitor using mica as the dielectric.
microphone -
Electro acoustic transducer that converts sound energy into electric energy.
microwave - Band
of very short wavelength radio waves within the UHF, SHF and EHF bands.
mid-band gain - Gain
of an amplifier operating within its bandwidth.
mid-point bias - An
amplifier biased at the center of its DC load line.
mil - One thousandth of
an inch (0.001 in.)
Miller's theorem - A
theorem that allows you to represent a feedback capacitor as equivalent input
and output shunt capacitors.
minority carriers -
The conduction band holes in n-type material and valence band electrons in
p-type material. Most minority carriers are produced by temperature rather than
by doping with impurities.
mismatch - Term
used to describe a difference between the output impedance of a source and the
input impedance of a load. A mismatch prevents the maximum transfer of power
from source to load.
modulation -
Process by which an information signal (audio for example) is used to modify
some characteristic of a higher frequency wave known as a carrier (radio for
example).
monostable multivibrator - A multivibrator with one stable output state. When
triggered, the circuit output will switch to the unstable state for a
predetermined period of time and then return to the stable state. A timer.
molecule -
Smallest particle of a compound that still retains its characteristics.
MOSFET -
Abbreviation for "metal oxide field effect transistor" also known as
an "insulated gate field effect transistor). A field effect transistor in
which the insulating layer between the gate electrode and the channel is a
metal oxide layer.
moving coil microphone - Microphone that uses a moving coil within a fixed magnetic
field. Dynamic microphone.
moving coil pick-up -
Dynamic phonograph pick-up in which the stylus causes a coil to move within a
fixed magnetic field.
moving coil loudspeaker - Loudspeaker that uses a moving "voice coil"
placed within a fixed magnetic field. Audio frequency current in the voice coil
causes movement which is mechanically transferred to the speaker cone. Also
known as a dynamic loudspeaker.
multimeter -
Electronic test equipment that can perform multiple tasks. Typically one
capable of measuring voltage, current and resistance. More sophisticated modern
digital multimeters also measure capacitance, inductance, current gain of
transistors and/or anything else that can be measured electronically.
multiplier resistor -
Resistor connected in series with a moving coil meter movement to extend the
voltage ranges.
multi segmant display -
Device made of several light emitting diodes arranged in a numeric or
alphanumeric pattern. By lighting selected segments numeric or alphabet
characters can be displayed.
multivibrator - A
class of circuits designed to produce square waves or pulses. Astable
multivibrators produce continuous pulses without an external stimulus or
trigger. Monostable multivibrators produce a single pulse for some
predetermined period of time only when triggered. Bistable multivibrators
produce a DC output which is stable in either one of two states. Either high or
low. An external stimulus or trigger is required for the bistable circuit to
change states, either high to low or low to high.
mutual inductance -
Ability of one inductor's lines of force to link with another inductor.
n-type semiconductor - A semiconductor compound
formed by doping an intrinsic semiconductor with a pentavalent element. An
n-type material contains an excess of conduction band electrons.
negative -
Terminal that has an excess of electrons.
negative charge - A
charge that has more electrons than protons
negative feedback -
A feedback signal 180° out of phase with an amplifier input signal. Used to
increase amplifier stability, bandwidth and input impedance. Also reduces distortion.
negative ground - A
system where the negative terminal of the source is connected to the system's
metal chassis.
negative ion - An
atom having a greater number of electrons in orbit than there are protons in
the nucleus.
negative resistance -
A resistance such that when the current through it increases the voltage drop
across the resistance decreases.
negative temperature coefficient - A term used to describe a component whose resistance or
capacitance decreases when temperature increases.
neon bulb - Glass
envelope filled with neon gas which when ionized by an applied voltage will
glow red.
network -
Combination of interconnected components, circuits or systems.
neutral - A
terminal, point or object with balanced charges. Neither positive or negative.
neutral atom - An
atom in which the number of negative charges (electrons in orbit) is equal to
the number of positive charges (protons in the nucleus).
neutral wire - The
conductor of a polyphase circuit or a single-phase three wire circuit that is intended
to have a ground potential. The potential difference between the neutral and
each of the other conductors are approximately equal in magnitude and equally
spaced in phase.
neutron -
Subatomic particle in the nucleus of an atom and having no electrical charge.
nickel-cadmium cell -
A secondary cell that uses a nickel oxide positive electrode and a cadmium
negative electrode.
node -
Junction or branch point in a circuit.
noise -
Unwanted electromagnetic radiation within an electrical or mechanical system.
An
operational amplifier circuit having no phase inversion between the input and
output.
non-inverting input -
The terminal on an operational amplifier that is identified by a plus sign.
non-linear scale - A
scale in which the divisions are not equally spaced.
normal closed -
Designation which states that the contacts of a switch or relay are closed or
connected when at rest. When activated, the contacts open or separated.
normally open -
Designation which states that the contacts of a switch or relay are normally
open or not connected. When activated the contacts close or become connected.
north pole - Pole
of a magnet out of which magnetic lines of force are assumed to originate.
Norton's theorem - Any
network of voltage sources and resistors can be replace by a single current
source in parallel with a single resistor.
notch filter - A
filter which blocks a narrow band of frequencies and passes all frequencies
above and below the band.
npn transistor - A
bipolar junction transistor in which a p-type base element is sandwiched
between an n-type emitter and an n-type collector.
nucleus - Core
of an atom. The nucleus contains both positive (protons) and neutral (neutrons)
subatomic particles.
octave - Interval between two sounds
whose fundamental frequencies differ by a ratio of 2 to 1. 440 Hz. is one
octave above 220 Hz.
offset null - An op
amp control pin used to eliminate the effects of internal component voltages on
the output of the device.
ohm - Unit of
resistance symbolized by the Greek capital letter omega (W).
ohmmeter -
Device used to measure electrical resistance.
Ohm's law -
Relationship between voltage, current and resistance. Ohm's law states that
current in a resistance varies in direct proportion to voltage applied and
inversely proportional to resistance.
Ohms per volt -
Refers to a value of ohms per volt of full scale defection for a moving coil
meter movement. The number of ohms per volt is the reciprocal of the amount of
current required to produce full scale deflection of the needle. A meter
requiring 50 microamps for full scale deflection has an internal resistance of
20 kW per volt. The higher the ohms per volt rating, the more sensitive the
meter.
one-shot -
Monostable multivibrator.
op-amp -
Abbreviation for operational amplifier.
open loop gain - Gain
of an amplifier when no feedback is present.
open loop mode - An
amplifier circuit having no means of comparing the output with the input. (No
feedback.)
operational amplifier -
A high gain DC amplifier that has a high input impedance and a low output
impedance. Op-amps are the most basic type of linear integrated circuits.
oscillate - To
produce a continuous output waveform without an input signal present.
oscillator - An
electronic circuit that produces a continuous output waveform with only DC
applied.
oscilloscope - An
instrument used to display a signal graphically. Shows signal amplitude, period
and wave shape in addition to any DC voltage present. A multiple trace
oscilloscope can show two or more waveforms at the same time for phase
comparison and timing measurements.
out of phase - When
the maximum and minimum points of two or more waveshapes do not occur at the
same time.
output -
Terminal at which a component, circuit or piece of equipment delivers current,
voltage or power.
output impedance -
Impedance measured across the output terminals of a device without a load
connected.
output power -
Amount of power a component, circuit or system can deliver to a load.
overload -
Condition that occurs when the load is greater than the system was designed to
handle. (Load resistance too small, load current too high.) Overload results in
waveform distortion and/or overheating.
overload protection -
Protective device such as a fuse or circuit breaker that automatically
disconnects a load when current exceeds a predetermined value.
paper capacitor - Fixed capacitor using oiled
or waxed paper as a dielectric.
parallel -
Circuit having two or more paths for current flow. Also called shunt.
parallel resonant circuit - Circuit having an inductor and a capacitor in parallel
with one another. Circuit offers a high impedance at resonant frequency.
Sometimes called a "tank circuit."
pass band - The
range of frequencies that will be passed and amplified by a tuned amplifier.
Also the range of frequencies passed by a band pass filter.
passive component -
Component that does not amplify a signal. Resistors and capacitors are
examples.
passive filter - A
filter that contains only passive or non amplifying components.
passive system -
System that emits no energy. It only receives. It does not transmit or reveal
its position.
peak -
Maximum or highest amplitude level.
peak inverse voltage -
(PIV) The maximum rated value of a AC voltage acting in the direction opposite
to that in which a device is designed to pass current.
peak to peak -
Difference between the maximum positive and maximum negative values of an AC
waveform.
pentavalent element -
Element whose atoms have five valence electrons. Used in doping intrinsic
silicon or germanium to produce n-type semiconductor material. Most commonly
used pentavalent materials are arsenic and phosphorus.
percent of regulation -
The change in output voltage that occurs between no-load and full-load in a DC
voltage source. Dividing this change by the full-load value and multiplying the
result by 100 gives percent regulation.
percent of ripple -
The ratio of the effective rms value of ripple voltage to the average value of
the total voltage. Expressed as a percentage.
period - Time
to complete one full cycle of a periodic or repeating waveform.
permanence -
Magnetic equivalent of magnetic inductance and consequently equal to the
reciprocal of reluctance, just as conductance is equal to the reciprocal of
resistance.
permanent magnet -
Magnet normally made of hardened steel that retains its magnetism indefinitely.
permeability -
Measure of how m how much better a material is as a path for magnetic lines of
force with respect to air which has a permeability of one. Symbolized by the
Greek lower case letter mu (m).
phase -
Angular relationship between two waves.
phase angle - Phase
difference between two or more waves, normally expressed in degrees.
phase shift -
Change in phase of a wave form between two points, expressed as degrees of lead
or lag.
phase shift oscillator - An oscillator that uses three RC networks in its feedback
path to produce the 180° phase shift required for oscillation.
phase splitter -
Circuit that takes a single input signal and produces two output signals that
are 180° apart in phase.
phonograph - Piece
of equipment used to reproduce sound stored on a disk called a phonograph
record.
phosphor -
Luminescent material applied to the inner face of a cathode ray tube that when
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photoconductive cell -
Material whose resistance decreases or conductance increases when exposed to
light.
photoconduction - A
process by which the conductance of a material is change by incident
electromagnetic radiation in the visible light spectrum.
photo detector -
Component used to detect or sense light.
photodiode - A
semiconductor diode that changes its electrical characteristics in response to
illumination.
photometer - Meter
used to measure light intensity.
photon -
Discrete portion of electromagnetic energy. A small packet of light.
photoresistor - Also
known as a photoconductive cell or light dependent resistor. (LDR) A device
whose resistance decreases with exposure to light.
photovoltaic cell -
Component commonly called a solar cell used to convert light energy into
electrical energy.
pi - Value
representing the ratio between the circumference and diameter of a circle and
equal to approximately 3.142.
pierce oscillator -
A variation of the colpitts oscillator. This oscillator uses a quartz crystal
in place of the inductor found in the colpitts oscillator feedback network. The
crystal maintains a highly stable output frequency.
piezoelectric crystal -
Crystal material that will generate a voltage when mechanical pressure is applied
and conversely will undergo mechanical stress when subjected to a voltage.
piezoelectric effect -
The production of a voltage between opposite sides of a piezoelectric crystal
as a result of pressure or twisting. Also the reverse effect which the application
of a voltage to opposite sides causes a deformation to occur at the frequency
of the applied voltage. (Converts mechanical energy into electrical energy and
electrical energy into mechanical energy.)
pinch-off region - A
region on the characteristic curve of a FET in which the gate bias causes the
depletion region to extend completely across the channel.
plastic film capacitor - Capacitor in which alternate layers of aluminum foil are
separated by thin films of plastic dielectric.
plate -
Conductive electrode in either a capacitor or battery. In vacuum tube
technology, it is the name given to the anode.
plug -
Movable connector that is normally connected into a socket or jack.
pnp transistor - A
bipolar junction transistor with an n-type base and p-type emitter and
collector.
pole - In an
active filter, a single RC circuit. A one pole filter has one capacitor and one
resistor. A two pole filter has two RC circuits and so on.
polar coordinates -
Either of two numbers that locate a point in a plane by its distance from a
fixed point and the angle this line makes with a fixed line.
polarity - Term
used to describe positive and negative charges.
polarized - A
component which must be connected in correct polarity to function and/or d/or
prevent destruction. Example: Electrolytic capacitor.
positive -
Polarity of point that attracts electrons as opposed to negative which supplies
electrons.
positive charge - A
charge that exists in a body that has fewer electrons than protons.
positive feedback -
A feedback signal that is in phase with an amplifier input signal. Positive
feedback is necessary for oscillation to occur.
positive ground - A
system whereby the positive terminal of the source is connected to the system's
conducting chassis.
positive ion - Atom
that has lost one or more valence electrons resulting in a net positive charge.
potential difference -
Voltage difference between two points which will cause current to flow in a
closed circuit.
potential energy -
Energy that has potential to do work because of its position relative to
others.
potentiometer - A
variable resistor with three terhree terminals. Mechanical turning of a shaft
can be used to produce variable resistance and potential. Example: A volume
control is usually a potentiometer.
power -
Amount of energy converted by a circuit or component in a unit of time,
normally seconds. Measured in units of watts. (joules/second).
power amplifier - An
amplifier designed to deliver maximum power output to a load. Example: In an
audio system, it is the power amplifier that drives the loudspeaker.
power derating factor -
A transistor rating that tells how much the maximum allowable value of PD decreased
for each 1°C rise in ambient temperature.
power dissipation -
Amount of heat energy generated by a device in one second when current flows
through it.
power factor - Ratio
of actual power to apparent power.
power loss - Ratio
of power absorbed to power delivered.
power supply -
Electrical equipment used to deliver either AC or DC voltage.
power supply rejection ratio - A measure of an op-amps ability to maintain a constant
output when the supply voltage varies.
primary - First
winding of a transformer. Winding that is connected to the source as opposed to
secondary which is a winding connected to a load.
primary cell - Cell
that produces electrical energy through an internal electrochemical action.
Once discharged a primary cell cannot be reused.
printed circuit board -
Insulating board containing conductive tracks for circuit connections.
programmable UJT - Unijunction
transistor with a variable intrinsic stand-off ratio.
propagation -
Traveling of electromagnetic, electrical or sound waves through a medium.
propagation delay -
Time required for a signal to pass through a device or circuit.
propagation time - Time
required for a wave to travel between two points.
protoboard - Board
with provision for attaching components without solder. Also called a
breadboard. Primarily used for constructing experimental circuits.
proton - Sub
atomic particle within the nucleus of an atom. Has a positive charge.
pulse - Rise
and fall of some quantity (usually voltage) for a period of time.
pulse fall time - Time
for a pulse to decrease from 90% of its peak value to 10% of its peak value.
pulse repetition frequency - The number of times per second that a pulse is
transmitted. Pulse rate.
pulse repetition time -
Time interval between the start of two consecutive pulses.
pulse rise time - Time
required for a pulse to increase from 10% of its peak value to 90% of its peak
value.
pulse width - Time
interval between the leading edge and trailing edge of a pulse at a point where
the amplitude is 50% of the peak value.
push>push-pull amplifier - Amplifier using two active devices operating 180° apart.
Pythagorean theorem - A theorem in geometry: The square of the hypotenuse of a right
triangle equals the sum of the squares of the other two sides. In electronics
used for vector analysis of AC circuits
Q - Quality factor of an inductor or capacitor. It
is the ratio of a component's reactance (energy stored) to its effective series
resistance (energy dissipated). For a tuned circuit, a figure of merit used in
bandwidth calculations. Q is the ratio of reactive power to resistive power in
a tuned circuit. Also the symbol for charge in coulombs (Q for quantity).
quiescent - At rest. For an amplifier the term is used to
describe a condition with no active input signal.
quiescent point - (Q point) A point on the DC load line of a
given amplifier that represents the quiescent (no signal) value of output
voltage and current for the circuit.
radar - Acronym for "radio
detection and ranging" A system that measures the distance and direction
of objects.
radio astronomy -
Branch of astronomy that studies the radio waves generated by celestial bodies
and uses these emissions to obtain information about them.
radio broadcast -
Transmission of music, voice and other information on radio carrier waves that
can be received by the general public.
radio communication -
Term used to describe the transfer of information between two or more points by
use of radio or electromagnetic waves.
radio-frequency amplifier - Amplifier having one or more active devices to amplify
radio signals.
radio-frequency generator - Generator capable of supplying RF energy at any desired
frequency in the radio-frequency spectrum.
radio-frequency probe -
Probe used in conjunction with an AC meter to measure radio-frequency signals.
RC - Abbreviation for
"resistance capacitance" also abbreviation for "radio
controlled" as in "RC model airplanes."
RC time constant -
Product of resistance and capacitance in seconds.
reactance -
Symbol "X". Opposition to current flow without the dissipation of
energy. Example: The opposition provided by inductance or capacitance to AC
current.
reactive power - Also
called imaginary power or wattles power. It is the power value in "volt
amps" obtained from the product of source voltage and source current in a
reactive circuit.
real number -
Number having no imaginary part.
receiver - Unit
or piece of equipment used to receive information.
recombination -
Process by which a conduction band electron gives up energy (in the form of
heat or light) and falls into a valence band hole.
rectangular coordinates - A Cartesian coordinate of a Cartesian coordinate system whose
straight-line axes or coordinate planes are perpendicular.
rectangular wave - Also
known as a pulse wave. A repeating wave that only operates between two levels
or values and remains at one of these values for a small amount of time
relative to the other value.
rectification -
Process that converts alternating current to direct current.
rectifier - Diode
circuit that converts alternating current into pulsating direct current.
reed relay - Relay
consisting of two thin magnetic strips within a glass envelope. When a coil
around the envelope is energized, the relay's contacts snap together making a
connection between leads attached to the reed strips.
regenerative feedback -
Positive feedback. Feedback from the output of an amplifier to the input such that
the feedback signal is in phase with the input signal. Used to produce
oscillation.
regulated power supply - Power supply that maintains a constant output voltage
under changing load conditions.
regulator -
Device or circuit that maintains a desired output under changing conditions.
relay -
Electromechanical device that opens or closes contacts when a current is passed
through a coil.
relative - Not
independent. Compared with or with respect to some other measured quantity.
relaxation oscillator -
Free running circuit that outputs pulses with a period dependent or one or more
RC time constants.
reluctance -
Resistance to the flow of magnetic lines of force.
remanence -
Amount a material remains magnetized after the magnetizing force has been
removed.
residual magnetism -
Magnetism remaining in the core of an electromagnet after the coil current is
removed.
resistance -
Symbolized "R" and measured in ohms. Opposition to current flow and
dissipation of energy in the form of heat.
resistive power -
Amount of power dissipated as heat in a circuit containing resistive and
reactive components. True power as opposed to reactive power.
resistive temperature detector - (RTD) Temperature detector consisting of a fine coil of
conducting wire (such as platinum) that will produce a relatively linear
increase in resistance as temperature increases.
receptivity -
Measure of a material's resistance to current flow.
resistor -
Component made of material that opposes flow of current and therefore has some
value of resistance.
resistor color code -
Coding system of colored stripes on a resistor to indicate the resistor's value
and tolerance.
resonance -
Circuit condition that occurs at the frequency where inductive reactance (XL)
equals capacitive reactance (XC).
reverse bias - Bias
on a PN junction that allows only leakage current (minority carriers) to flow.
Positive polarity on the n-type material and negative polarity to the p-type
material.
reverse breakdown voltage - Amount of reverse bias that will cause a PN junction to
break down and conduct in the reverse direction.
reverse current -
Current through a diode when reverse biased. An extremely small current also
referred to as leakage.
reverse saturation current - Reverse current through a diode caused by thermal activity.
This current is not affected by the amount of reverse bias on the component,
but does vary with temperature.
RF - Abbreviation for
"radio frequency."
rheostat - Two
terminal variable resistor used to control current.
right angle triangle -
Triangle having a 90° or square corner.
ripple frequency -
Frequency of the ripple present in the output of a DC source.
ripple voltage - The
small variations in Dc voltage that remain after filtering in a power supply.
rise time - Time
for the leading edge of a pulse to rise from 10% of its peak value to 90% of
its peak value.
RL differentiator -
An RL circuit whose output voltage is proportional to the rate of change of the
input voltage.
RL filter -
Selective circuit of resistors and inductors that offers little or no
opposition to certain frequencies while blocking or attenuating other
frequencies.
RL integrator - RL
circuit with an output proportionate to the integral of the input signal.
rms - Abbreviation for
"root mean square"
rms value - Rms
value of an AC sine wave is 0.707 times the peak value. This is the effective
value of an AC sine wave. The rms value of a sine wave is the value of a DC
voltage that would produce the same amount of heat in a heating element.
roll-off rate - Rate
of change in gain when an amplifier is operated outside of its bandwidth.
rotary switch -
Electromechanical device that has a rotating shaft connected to one terminal
capable of making or breaking a connection to one or more other terminals.
R-2R ladder -
Network or circuit composed of a sequence of L networks connected in tandem.
Circuit used in digital to analog converters.
saturation - Condition in which a
further increase in one variable produces no further increase in the resultant
effect. In a bipolar junction transistor, the condition when the emitter to
collector voltage is less than the emitter to base voltage. This condition puts
forward bias on the base to collector junction.
sawtooth wave -
Repeating waveform that rises from zero to maximum value linearly drops back to
zero and repeats. A ramp waveform.
scale - Set
of markings used for measurement.
schematic diagram -
Illustration of an electrical or electronic circuit with the components
represented by their symbols.
Schmitt trigger -
Circuit to convert a given waveform to a square wave output.
Schottky diode - High
speed diode that has very little junction capacitance. Also known as a
"hot-carrier diode" or a "surface-barrier diode."
scientific notation -
Numbers entered as a number from one to ten multiplied by a power of ten.
Example: 8765 = 8.765 × 103.
secondary -
Output winding of a transformer. Winding that is connected to a load.
secondary cell -
Electrolytic cell used to store electricity. Once discharged may be restored by
recharging by putting current through the cell in the direction opposite to
that of discharge current.
selectivity -
Characteristic of a circuit to discriminate between wanted and unwanted
signals.
self biasing - Gate
bias for a field effect transistor in which source current through a resistor
produces the voltage for gate to source bias.
self inductance -
Property that causes a counter electromotive force to be produced in a
conductor when the magnetic field expands or collapses with a change of
current.
semiconductor - An
element which is neither a good conductor or a good insulator, but rather lies
somewhere between the two. Characterized by a valence shell containing four
electrons. Silicon, germanium and carbon are the semiconductors most frequently
used in electronics.
series circuit -
Circuit in which the components are connected end to end so that current has
only one path to follow through the circuit.
series parallel network - Network that contains components connected in both series
and parallel.
series resonance -
Condition that occurs in a series LC circuit at the frequency where inductive
reactance equals capacitive reactance. Impedance is minimum, current is maximum
limited only by resistance in the circuit.
seven segment display -
Device made of several light emitting diodes arranged in a numeric or
alphanumeric pattern. By lighting selected segments numeric or alphabet
characters can be displayed.
shells or bands -
Orbital path containing a group of electrons having a common energy level.
shield - Metal
grounded cover used to protect a wire, component or piece of equipment from
stray magnetic and/or electric fields.
short circuit - Also
called a short. Low resistance connection between two points in a circuit
typically causing excessive current.
shunt resistor -
Resistor connected in parallel or in shunt with another component or circuit.
signal -
Electrical quantity that conveys information.
signal to noise ratio -
Ratio of the magnitude of the signal to the magnitude of noise usually
expressed in decibels.
silicon - (Si)
Non metallic element (atomic number 14) used in pure form as a semiconductor.
silicon-controlled rectifier - (SCR) Three terminal active device that acts as a gated
diode. The gate terminal is used to turn the device on allowing current to pass
from cathode to anode.
silicon controlled switch - An SCR with an added terminal called an anode gate. A
positive pulse either at the anode gate or the cathode gate will turn the
device on.
silicon dioxide - Glass
like material used as the gate insulating material in a MOSFET.
silicon transistor -
A bipolar junction transistor using silicon as the semi conducting material.
silver - (Ag)
Precious metal that does not easily corrode and is more conductive than copper.
silver mica capacitor -
Mica capacitor with silver deposited directly onto the mica sheets instead of
using conductive metal foil.
silver solder -
Solder composed of silver, copper and zinc. Has a melting point lower than pure
silver, but higher than lead-tin solder.
simplex -
Communication in only one direction at a time. Example: FAX.
simulcast -
Broadcasting a program simultaneously in two different forms, for example a
program broadcast in both AM and FM.
sine - Sine
of an angle of a right angle triangle is equal to the opposite side divided by
the hypotenuse.
sine wave - Wave
whose amplitude is the sine of a linear function of time. It is plotted on a
graph that plots amplitude against time or radial degrees relative to the
angular rotation of an alternator.
single in-line package - Package containing several electronic components
(generally resistors) with a single row of connecting pins.
single pole double throw - (SPDT) Three terminal switch in which one terminal can be
connected to either one of the other terminals.
single pole single throw - (SPST) Two terminal switch or relay that can open or close
one circuit.
single sideband - (SSB)
AM radio communication technique in which the transmitter suppresses one
sideband and therefore transmits only a single sideband.
single throw switch -
Switch containing only one set of contacts which can be either opened or
closed.
sink -
Device such as a load that consumes power or conducts away heat.
sintering -
Process of bonding either a metal or powder by cold pressing it into a desired
shape and then heating to form a strong cohesive body.
sinusoidal -
Varying in proportion to the sine of an angle or time function. AC voltage in
which the instantaneous value is equal to the sine of the phase angle times the
peak value.
SIP - Abbreviation for
"single in-line package."
skin effect -
Tendency of high-frequency (rf) currents to flow near the surface layer of a
conductor.
slew rate - The
maximum rate at which the output voltage of an op-amp can change.
slide switch -
Switch having a sliding button, bar or knob.
slow acting relay -
Slow operating relay that when energized may not pull up the armature for
several seconds.
slow-blow fuse - Fust
that can withstand a heavy current (up to ten times its rated value) for a
small period of time before it opens.
snap switch -
Switch containing a spring under tension or compression that causes the
contacts to come together suddenly when activated.
SNR - Abbreviation for
"signal to noise ratio."
soft magnetic material - Ferromagnetic material that is easily demagnetized.
software -
Program of instructions that directs the operation of a computer.
solar cell -
Photovoltaic cell that converts light into electric energy. Especially useful
as a power source for space vehicles.
solder -
Metallic alloy used to join two metal surfaces.
soldering - Process
of joining two metallic surfaces to make an electrical contact by melting
solder (usually tin and lead) across them.
soldering iron - Tool
with an internal heating element used to heat surfaces being soldered to the
point where the solder becomes molten.
solenoid - An
air core coil. Equipped with a movable iron core the solenoid will produce
motion. As a result of current through the coil the iron core is pulled into
the center of the winding. When the coil is deenergized, a spring pulls the
movable core away from the center of the winding. Mechanical devices connected
to the movable core are made to move as a result of current through the coil.
Example: Electric door locks on some automobiles.
solid conductor -
Conductor having a single solid wire instead of strands of fine wire twisted
together.
solid state -
Pertaining to circuits where signals pass through solid semiconductor material
such as transistors and diodes as opposed to vacuum tubes where signals pass
through a vacuum.
sonar -
Acronym for "sound navigation and ranging." A system using reflected
sound waves to determine the position of some target.
sonic -
Pertaining to sound.
sound wave -
Pressure waves propagated through air or other plastic media. Sound waves are
generally audible to the human ear if the frequency is between approximately 20
and 20,000 vibrations per second. (hertz)
source -
Device that provides signal power or energy to a load.
source follower - FET
amplifier in which signal is applied between gate and drain with output taken
between source and drain. Also called "common drain."
source impedance -
Impedance through which output current is taken from a source.
south pole - Pole
of a magnet into which magnetic lines of force are assumed to enter.
spark -
Momentary discharge of electrical energy due to ionization of air or other
dielectric material separating two charges.
SPDT -
Single pole double throw.
speaker - Also
called "loudspeaker." Transducer that converts electrical energy into
mechanical energy at audio frequencies.
spectrum -
Arrangement or display of light or other forms of electromagnetic radiation
separated according to wavelength, energy or some other property.
spectrum analyzer -
Instrument used to display the frequency domain of a waveform plotting
amplitude against frequency.
speed-up capacitor -
Capacitor added to the base circuit of a BJT switching circuit to improve the
switching time of the device.
SPST -
Abbreviation for "single pole single throw."
square wave - Wave
that alternates between two fixed values for an equal amount of time.
static -
Crackling noise heard on AM radio receivers. Caused by electric storms or
electric devices.
static electricity -
Stationary electric charges.
static reverse current - Reverse current through a zener diode when the reverse
voltage across the diode is less than the zener voltage rating of the device.
stator -
Stationary part of some rotary device such as a variable capacitor.
step-down transformer -
Transformer in which the output AC voltage is less than the input AC voltage.
step-up transformer -
Transformer in which the output AC voltage is greater than the input AC
voltage.
stereo sound -
System in which reproduced sound is delivered through two or more channels to
give a sense of direction to the source.
stop band - Range
of frequencies outside the pass band of a tuned amplifier.
storage time - In a
BJT switching circuit, it is the time required for collector current to drop
from 100% to 90% of its maximum value.
stranded conductor -
Conductor composed of a group of strands of wire twisted together.
stray capacitance -
Undesirable capacitance that exists between two conductors such as two leads or
one lead and a metal chassis.
subassembly -
Components contained in a unit for convenience in assembling or servicing equipment.
subatomic -
Particles such as electrons, protons and neutrons that are smaller than atoms.
substrate -
Mechanical insulating support upon which a device is fabricated.
summing amplifier -
An op-amp circuit whose output is proportional to the sum of its instantaneous
voltages.
superconductor - Metal
such as lead or niobium that, when cooled to within a few degrees of absolute
zero, can conduct current with no resistance.
super heterodyne receiver - Radio receiver that converts all radio frequencies to a
fixed intermediate frequency to maximize gain and bandwidth before
demodulation.
super high frequency - (SHF) Frequency band between 3 GHz and 30 GHz. So designated by
Federal Communications Commission (FCC).
superposition theorem -
Theorem designed to simplify networks containing two or more sources. It states
that in a network containing more than one source, the current at any one point
is equal to the algebraic sum of the currents produced by each source acting
separately.
supply voltage -
Voltage provided by a power source.
surface-barrier diode -
(Schottky diode) High speed diode that has very little junction capacitance.
Also known as a "hot-carrier diode."
surface leakage current - Diode reverse current that passes along the surface of the
semiconductor materials.
surge current - High
charging current that flows into a power supply filter capacitor as the power
is first turned on.
sweep generator - Test
instrument designed to produce a voltage that continuously varies in frequency
over a band of frequencies. Used as a source to display frequency response of a
circuit on an oscilloscope.
switch -
Electrical device having two states, on (closed) or off (open). Ideally having
zero impedance when closed and infinite impedance when open.
switching transistor -
transistor designed to change rapidly between saturation and cut-off.
synchronization - Also
called sync. Precise matching of two waves or functions.
synchronous - Two
or more signals in step or in phase.
sync pulse - Pulse
used as a reference for synchronization.
system -
Combination of several pieces of equipment to perform in a particular manner.
tank circuit - Parallel resonant circuit
containing only a coil and a capacitor. Both the coil and capacitor store
electrical energy for part of each cycle.
tantalum capacitor -
Electrolytic capacitor having a tantalum foil anode. Able to have a large
capacity in a small package.
tap - Electrical
connection to some point other than at the ends of a resistor or inductor.
tapered - Non unifrom
distribution of resistance per unit length throughout the element of a
potentiometer.
technician -
Expert in troubleshooting circuit and system malfunctions. Along with a
thorough knowledge of test equipment and how to use it to diagnose problems, the
technician is also familiar with how to repair or replace faulty components.
Technicians basically translate theory into action.
telegraphy -
Communication between two points by sending and receiving a series of current
pulses either through wire or by radio.
telemetry -
Transmission of instrument readings to a remote location either by wire or by
radio.
telephone -
Apparatus designed to convert sound waves into electrical waves which are sent
to and reproduced data distant point.
telephone line - Wires
existing between subscribers and central stations in a telephone system.
telephony -
Telecommunications system involving the transmission of speech information,
allowing two or more persons to communicate verbally.
teletypewriter -
Electric typewriter that like a tele-printer can produce coded signals
corresponding to the keys pressed or print characters corresponding to the
coded signals received.
television -
System that converts both audio and visual information into corresponding
electrical signals which are then transmitted through wires or by radio waves
to a receiver which reproduces the original information.
telex -
Teletypewriter exchange service.
temperature coefficient of frequency - Rate at which frequency changes with temperature.
tera - (T)
Metric prefix that represents 1012.
terminal - Point
at which electrical connections are made.
tesla - (T)
Unit of magnetic flux density. (1 tesla = 1 Wb/m2).
test -
Sequence of operations intended to verify the correct operation or
malfunctioning of a piece of equipment or system.
thermal relay - Relay
activated by a heating element.
thermal runaway -
Problem that can develop in an amplifier when an increase in temperature causes
an increase in collector current. The increase in collector current causes a further
increase in temperature and so on. Unless the circuit is designed to prevent
this condition, the device can be driven into saturation.
thermal stability -
The ability of a circuit to maintain stable characteristics in spite of
increased temperature.
thermistor -
Temperature sensitive semiconductor that has a negative temperature coefficient
of resistance. As temperature increases, resistance decreases.
thermocouple -
Temperature transducer consisting of two dissimilar metals welded together at
one end to form a junction that when heated will generate a voltage.
thermometry -
Relating to the measuring of temperature.
thermostat -
Device that opens or closes a circuit in response to changes in temperature.
Thevenin's theorem -
Theorem that replaces any complex network with a single voltage source in
series with a single resistance.
thick-film capacitor -
Capacitor consisting of two thick-film layers of conductive film separated by a
deposited thick-layer dielectric film.
thick film resistor -
Fixed value resistor consisting of thick-film resistive element made from metal
particles and glass powder.
thin film capacitor -
Capacitor in which both the electrodes and the dielectric are deposited in
layers on a substrate.
thin film detector -
(TFD) A temperature detector containing a thin layer of platinum and used for
precise temperature readings.
three phase supply -
AC supply that consists of three AC voltages 120° out of phase with each other.
threshold -
Minimum point at which an effect is produced or detected.
threshold voltage -
For an enhancement MOSFET, the minimum gate source voltage required for
conduction of source drain current.
thyristor - A
term used to classify all four layer semiconductor devices. SCRs and triacs are
examples of thyristors.
time constant - (t)
Time required for a capacitor in an RC circuit to charge to 63% of the
remaining potential across the circuit. Also time required for current to reach
63% of maximum value in an RL circuit. Time constant of an RC circuit is the
product of R and C. Time constant of an RL circuit is equal to inductance
divided by resistance.
time division multiplexing - (TDM) Transmission of two or more signals on the same
path, but at different times.
time-domain analysis -
A method of representing a waveform by plotting amplitude over time.
toggle switch -
Spring loaded switch that is put in one of two positions either on or off.
tolerance -
Permissible deviation from a specified value normally expressed as a
percentage.
TO package -
Cylindrical, metal can type of package of some semiconductor components.
toroidal coil - Coil
wound on a doughnut shaped core.
transconductance - Also
called mutual conductance. Ratio of a change in output current to the change in
input voltage that caused it.
transducer -
Device that converts energy from one form to another.
transformer -
Inductor with two or more windings. Through mutual inductance, current in one
winding called a primary will induce current into the other windings called
secondaries.
transformer coupling -
Also called inductive coupling. Coupling of two circuits by means of mutual
inductance provided by a transformer.
transistor - Term
derived from "transfer resistor." Semiconductor device that can be
used as an amplifier or as an electronic switch.
transmission -
Sending of information.
transmission line -
Conducting line used to transmit signal energy between two points.
transmitter -
Equipment used to achieve transmission.
triac -
Bidirectional gate controlled thyristor similar to an SCR, but capable of conducting
in both directions. Provides full wave control of AC power.
triangular wave - A
repeating wave that has equal positive going and negative going ramps. The
ramps have linear rates of change with time.
trigger - Pulse
used to initiate a circuit action.
triggering -
Initiation of an action in a circuit which then functions for a predetermined
time. Example: The duration of one sweep in a cathode ray tube.
trimmer - Small
value variable capacitor, resistor or inductor used to fine tune a larger value.
trivalent element -
One having three valence electrons. Used as an impurity in semiconductor
material to produce p-type material. Most commonly used trivalent elements are:
Aluminum, Gallium and Boron.
troubleshooting -
Systematic approach to locating the cause of a fault in an electronic circuit
or system.
tuned circuit -
Circuit that can have its component values adjusted so that it responds to one
selected frequency and rejects all others.
tunnel diode -
Heavily doped junction diode that has negative resistance in the forward
direction of its operating range.
turn-off time - Sum
of storage time and fall time.
turn-on time - Sum
of delay time and rise time.
turns ratio - Ratio
of the number of turns in the secondary winding of a transformer to the number
of turns in the primary winding.
two phase - Two
repeating waveforms having a phase difference of 90°.
UHF - Abbreviation for
"ultra high frequency.
ultrasonic -
Signals that are just above the frequency range of human hearing of
approximately 20 kHz.
uncharged -
Material having atoms with the same number of electrons in orbit as the number
of protons in the nucleus. Having no electrical charge.
unijunction transistor - Three terminal device that acts as a diode with its own
internal voltage divider biasing circuit.
unity gain frequency -
Frequency of operation for a device where the gain of the component drops to
unity.
VA - Abbreviation for "volt
ampere"
vacuum tube -
Electron tube evacuated to such a degree that its electrical characteristics
are essentially unaffected by the presence of residual gas or vapor. Have been
essentially replaced by transistors for amplification and rectification.
Cathode ray tubes are still used as display devices.
valence shell - The
outermost electron shell for a given atom. The number of electrons in this
shell determines the conductivity of the atom.
varactor diode - PN
junction diode with a high junction capacitance when reverse biased. Most often
used as a voltage controlled capacitor. The varactor is also called: varicap,
tuning diode and epicap.
variable capacitor -
Capacitor whose capacitance can be change by varying the effective area of the
plates or the distance between the plates.
variable resistor -
Resistor whose resistance can be changed by turning a shaft. See also
"potentiometer and rheostat."
VCR - Abbreviation for
"video cassette recorder."
vector -
Quantity having both magnitude and direction. Normally represented by a line.
Length of the line indicates magnitude and orientation indicates direction.
vector diagram -
Arrangement of vectors showing phase relationships between two or more AC
quantities of the same frequency.
vertical MOS -
Enhancement type MOSFET designed to handle much greater values of drain current
than standard E-MOSFET.
very high frequency -
(VHF) Electromagnetic frequency band from 30 MHz to 300 MHz.
very low frequency -
(VLF) Frequency band from 3 kHz to 30 kHz.
video -
Relating to any picture or visual information. From the latin word meaning
"I see."
video amplifier -
Amplifier having one or mare stages designed to amplify video signals.
virtual ground - Point
in a circuit that is always at approximately ground potential. Often a ground
for voltage, but not for current.
voice coil - Coil
attached to the diaphragm of a moving coil loudspeaker. The coil is moved
through an air gap between magnetic pole pieces.
voice synthesizer -
Synthesizer that can simulate speech by stringing together phonemes.
volt - Unit
of potential difference or electromotive force. One volt is the potential difference
needed to produce one ampere of current through a resistance of one ohm.
voltage - (V)
Term used to designate electrical pressure or force that causes current to
flow.
voltage amplifier -
Amplifier designed to build up signal voltage. By design amplifiers can have a
large voltage gain or a large current gain or a large power gain. Voltage
amplifiers are designed to maximize voltage gain often at the expense of
current gain or power gain.
voltage controlled oscillator - Oscillator whose output frequency depends on an input
control voltage.
voltage divider - Fixed
or variable series resistor network connected across a voltage to obtain a
desired fraction of that voltage.
voltage divider biasing - Biasing method used with amplifiers in which two series
resistors connected across a source. The junction of the two biasing resistors
provides correct bias voltage for the amplifier.
voltage drop -
Voltage or difference in potential developed across a component due to current
flow.
voltage feedback -
Feedback configuration where a portion of the output voltage is fed back to the
input of an amplifier.
voltage follower -
Operational amplifier circuit characterized by a high input impedance, low
output impedance and unity voltage gain. Used as a buffer between a source and
a low impedance load.
voltage gain - Also
called voltage amplification. Ratio of amplifier output voltage to input
voltage usually expressed in decibels.
voltage multiplier -
Rectifier circuit using diodes and capacitors to produce a DC output voltage
that is some multiple of the peak value of AC input voltage. Cost effective way
of producing higher DC voltages. Voltage doublers and voltage triplers are
examples.
voltage rating -
Maximum voltage a component can withstand without breaking down.
voltage regulator -
Device or circuit that maintains constant output voltage (within certain
limits) in spite of changing line voltage and/or load current.
voltage source -
Circuit or device that supplies voltage to a load.
voltaic cell -
Primary cell having two unlike electrodes immersed in a solution that
chemically interacts to produce a voltage.
volt-ampere - Unit
of apparent power in an AC circuit containing capacitive or inductive
reactance. Apparent power is the product of source voltage and current.
voltmeter -
Instrument used to measure difference in potential between two points.
volume -
Magnitude or power level of audio frequency. Measured in volume units (VU).
watt - Unit of electrical power
required to do work at the rate of one joule per second. One watt of power is
expended when one ampere of direct current flows through a resistance of one
ohm. In an AC circuit, true power is the product of effective volts and
effective amperes, multiplied by the power factor.
wattage rating -
Maximum power a device can safely handle continuously.
watt-hour - Unit
of electrical work, equal to a power of one watt being absorbed for one hour.
wattmeter -
Instrument used to measure electric power in watts.
wave -
Electric, electromagnetic, acoustic, mechanical or other form whose physical
activity rises and falls or advances and retreats periodically as it travels
through some medium.
waveform - Shape
of a wave.
waveguide -
Rectangular or circular pipe used to guide electromagnetic waves at micro
frequencies.
wavelength - (l)
Distance between two points of corresponding phase and is equal to waveform
velocity divided by frequency.
weber - (Wb)
Unit of magnetic flux. One weber is the amount of flux that when linked with a
single turn of wire for an interval of one second will induce an electromotive
force of one volt.
wien-bridge oscillator - Oscillator that uses an RC low-pass filter and an RC
high-pass filter to set the frequency of oscillations.
wet cell -
Secondary cell using a liquid as an electrolyte.
wetting - Term
used in soldering to describe the condition that occurs when the metals being
soldered are hot enough to melt the solder so it flows over the surface.
wheatstone bridge -
Four arm bridge circuit used to measure resistance, inductance or capacitance.
wideband amplifier -
Also called "broadband amplifier." Amplifier with a flat response
over a wide range of frequencies.
winding - One
or more turns of a conductor wound in the form of a coil.
wire -
Single solid or stranded group of conductors having a low resistance to current
flow. Used to make connections between circuits or points in a circuit.
wire gauge -
American wire gauge (AWG) is a system of numerical designations of wire
diameters.
wireless - Term
describing radio communication that requires no wired between two communicating
points.
wire wound resistor -
Resistor in which the resistive element is a length of high resistance wire or
ribbon usually nichrome wound onto an insulating form.
wire wrapping -
Method of making a connection by wrapping wire around a rectangular pin.
woofer - Large
loudspeaker designed primarily to reproduce low frequency audio signals.
work - Work
is done any time energy is transformed from one type to another. The amount of
work done is dependent on the amount of energy transformed.
X - Symbol for reactance
X aY - Symbol for admittance.
Y axis - Vertical axis.
xis - Horizontal axis
Z axis - Axis perpendicular to both X and Y axes.
Zener Diode - Semiconductor diode in which reverse breakdown
voltage current causes the diode to develop a constant voltage. Used as a clamp
for voltage regulation.
Zeroing - Calibrating a meter so that it shows a value
of zero when zero is being measured.

Job hunting
Job
hunting or job seeking
is the act of looking for employment, due to unemployment or discontent with a
current position. The immediate goal of job seeking is usually to obtain a job
interview with an employer which may lead to getting hired. The job hunter or seeker typically first looks for job
vacancies or employment opportunities. Common methods of job hunting are:
*
using a job search engine
* looking through the classifieds in newspapers
* using a private or public employment agency or recruiter
* finding a job through a friend or an extended business network or personal network
IV.      Job hunting
Language notes
Position                                                          должность
Application                                                    заявление
Promising                                                       перспективный
Creativе                                                         творческий
Competitive                                                    конкурентоспособный
Responsibility                                                ответственность
Skilful –умелый. опытный,
Negotiations –переговоры,
Entrepreneur- предприниматель,
Fair – честный,
Reliability – надежность,
Letter of Recommendation-рекомендательное письмо,
length-продолжительность,
Experimental period – испытательный срок,
environment- окружающая среда,
excellent references – прекрасные отзывы,
job- работа,
Officer-должностное лицо,
To earn- зарабатывать
Charge-оплата любых услуг,
Salary – зарплата служащих,
Wages – зарплата рабочих
Bonus –премия,
 Labour contract (agreement) – трудовое соглашение
Deadline – конечный срок подачи чего-то, junior- младший по работе,
Red tape (разг) –канцелярская (бумажная работа), senior-старший по работе,

Word combinations
1)You have excellent
references from your previous job – У вас прекрасные отзывы с предыдущей
работы.                      2) What do you consider a fair salary? – Какую
зарплату Вы считаете достойной Вас?    3)The hours are from nine to five
thirty- Мы работаем с девяти до половины шестого.           4) Tell him not to sign the contract- Скажите ему, чтобы он не подписывал
контракт.            5) I am a Marketing Manager – So am I. - Я работаю менеджером по вопросам маркетинга.- Я тоже.

Overview
Networking
Contacting as many people as possible
is the best way to find a job. It is estimated that 60% or higher of all jobs
are found through networking. [http://jobsearch.about.com/cs/networking/a/networking.htm]

Applying
One can also go and hand out
résumés or Curriculum Vitae to prospective employers.
Another recommended method of job hunting is to use cold calling or emailing to
companies that one desires to work for and inquire to whether there are any job
vacancies.
Interviewing
Once an employer has received your
résumé, they will make a short list of potential employees to be
interviewed based on the resume and any other information contributed. During
the interview process, interviewers generally look for persons who they believe
will be best for the job and work environment. The interview may occur in
several rounds until the interviewer is satisfied and offers the job to the
applicant.
Types of Jobs
There are several types of jobs,
including full-time long-term regular jobs, internship, or contract jobs.
job-hunter — ˈjob ˌhunter
noun [countable] someone who is looking for a job; =job seeker: • She had just
embarked on a job hunt in Chicago
Before You Start Job Hunting
Your cover letter and resume or CV is
typically the first impression an employer will have of you. It needs to market
your relevant skills, knowledge, and accomplishments. The right resume and
cover letter is one of the most critical job search tools you can have. Once
your resume is in order you'll need to send it out via email or snail mail or
post it online. Our Resume and Cover
Letter Center steps you through writing, publishing, posting, and
submitting your resume and cover letter to employers and to jobs web sites.
 Tips for
Effective Job Hunting
It's always important to make sure you have covered all the bases when you are
in the midst of a job search. Review these ten tips to make sure your job
hunting is on the right track.
How to Find Job
Search Help
How job hunters can identify free, or inexpensive, job search and career
resources in their geographic areas.

DEVELOPMENT OF ELECTONICS

Electronics is a field of engineering and applied physics dealing with the
design  and

application of electronic circuits.
The operation of circuits
depends on the flow of electrons
for generation, transmission, reception and
storage of information.
Today it is difficult to imagine our life without electronics.It surrounds use
everywhere.
 Electronic devices are
widely used in scientific research and industrial
 designing,
they control
the work of plants and power stations,
calculate the trajectories of space ships
and help the people discover new
phenomena of nature.
Automatization of production processes and studieson living organisms became possible
due to electronics.
The invention of vacuum tubes at the beginning of the 20th century was,
 the
starting point of the rapid growth of modern electronics.
            Vacuum tubes
assisted in manipulation of signals.
 The development of a large variety of
tubes designed for specialized functions made possible
the progress in radiocommunication technology before the World War II and in the creation of
early  computers during and shortly after the war.The transistor invented by American scientists W
Shockly, J.Bardeen and W
Brattain in 1948 completely replaced the vacuum tube.
             The transistor, a
small piece of a semi
conductor with three electrodes,
 had great advantages over the best vacuum tubes.
It provided the same functions as the vacuum
tube  but at reduced  weight, cost,
power consumption, and with highreliability.

With the invention of the transistor all essential circuit functions
could be carried  out inside    solid bodies.
The aim of creating electronic circuits
with entirely solid state  components had
 finally been realized.

Early
transistors could respond at a rate of a few million times a second.

This was fast enough to serve in radio circuits, but far below the speed needed for
high speed computers
or for microwave communication systems.
  The progress in semiconductor
technology led to the
development of  the
integrated circuit, which was discovered due to
the efforts of John Kilby in1958.There appeared a new field of science — integrated electronics.
The
essence of it is batch processing.
Instead of making, testing and assembling
descrete components on a chip one at a time, large groupings of these
components together
 with their interconnections were made all at a time.

Developing of
Telecommunications

I would like to tell you about telecommunications and their
developing.
We can not deny the role of telecommunications in our life.
The Internet, phones, telegraph, cell phones, radio, television are all the
means of communication or telecommunication. Nowadays we live in information
era, when information is the key and engine of progress. Our society needs
perfect means of information exchange that is why all types of
telecommunication are under the permanent developing.
Currently hundreds of millions of people use wireless
communication means. Cell phone is no longer a symbol of prestige but a tool,
which lets to use working time more effectively. Considering that the main
service of a mobile connection operator is providing high quality connection,
much attention in the telecommunication market is paid to the spectrum of
services that cell network subscriber may receive.
Today we can easily connect to the Internet using our cell
phone or to take a picture or to take a short movie, using our video cell
phone.
Late in the nineteenth century, communication facilities
were augmented by a new invention — telephone. In the USA its use expanded
slowly and by 1900 the American Telephone and Telegraph Company controlled
855,000 telephones.
After 1900, telephone installations extended much more
rapidly in all the wealthier countries. The number of telephones in use in the
world grew at almost 100 per cent per decade. But long-distance
telephone services gradually developed and began to compete with telegraphic
business. A greater contribution to long-range communication came with the
development of wireless technology.
Before the outbreak of the First World War wireless
telegraphy was established as a means of regular communication with ships at
sea and provided a valuable supplement to existing telegraph lines. In the next
few years the telephone systems of all the chief countries were connected with
each other by radio. Far more immediate was the influence that radio had
through broadcasting and by television, which followed it at an interval of
about twenty-five years.
Telephones are as much a part of infrastructure of our
society as roads or electricity, and competition will make them cheaper. Losses
from lower prices will be countered by higher usage. Most important of all, by
cutting out the need to install costly cables and microwave transmitters, the
new telephones could be a boon to the remote and poor regions of the earth.
Even today, half the world's population lives more than two hours away from a
telephone.
Satellite phones are not going to deliver all their
benefits at once.

A computer
                       A computer is not an acronym and sometimes abbreviated
as comp or'puter. The term
"computer" was originally given to humans (human computers) who
performed numerical calculations using mechanical calculators, such as the abacus and slide rule. The term was later given to a
mechanical device as they began replacing the human computers. Today's
computers are electronic devices that accept data (input),process that data, produce output, and then store (storage) the results.
                       The first digital computer and what most people think of as a
computer was called the ENIAC, built during World War II (1943-1946). Early computers
like the ENIAC used vacuum tubes and were large (sometimes room size) and only
found in businesses, Universities, or governments. Later, computers began
utilizing transistors as well as smaller and cheaper parts that
allowed the common person to own a computer.

The history of the computer and when the
     first computer was invented.

Today, computers help make jobs that used to be
complicated much simpler. For example, you can write a letter in a word processor, edit it anytime, spell check, print copies, and send it to someone across
the world in a matter of seconds. All of these activities would have taken
someone days, if not months, to do before computers. Also, all of the above is
just a small fraction of what computers can do.
What components make up a computer?
Today's computers have
some or all of the below components (hardware). As technology advances, older technologies, such as a
floppy disk drive and Zip drive (both shown below), are no longer required or
included with computers.

Bay
Case or Chassis
Case Fan
Optical drive:Blu-ray, CD-ROM, CD-R,CD-RW,
     or DVD
CPU (processor)
Floppy disk drive
Hard drive
Keyboard
Memory (RAM)
Microphone
Monitor, LCD,
     or another display device
Motherboard
Mouse
Network card
Power Supply
Printer
Sound card
Speakers
Video card

What parts are needed for a computer to work?
A computer does not need
all of the components mentioned above. However, a computer cannot work without
having at the very minimum the below parts.

CPU (processor)
Memory (RAM)
Motherboard
Storage device (e.g. hard drive)

Hardware
Computer
hardware refers to the physical components that make up a computer
system.
There are many
different kinds of hardware that can be installed inside, and connected to the
outside, of a computer.
Computer
hardware may sometimes be seen abbreviated as computer hw.
Abbreviated
as HW, Hardware is best described as any physical
component of a computer system that contains a circuit board, ICs, or other electronics. A perfect example of
hardware is the screen on which you are viewing this page. Whether it be acomputer monitor, tablet or smartphone; it's hardware.
Without any hardware,
your computer would not exist, and software could not be used. The picture is aLogitech webcam, an example of an external hardwareperipheral. This hardware device allows users to take videos or pictures and
transmit them over the Internet.
Below is a list of external hardware and internal hardware that may be found with a computer.
External hardware examples

Flat-panel, Monitor,
     and LCD
Keyboard
Microphone
Mouse
Printer
Projector
Scanner
Speakers
USB thumb drive

Internal hardware examples

CPU
Drive (e.g. Blu-Ray, CD-ROM, DVD, floppy drive,
     and hard drive)
Fan (heat sink)
Modem
Motherboard
Network card
RAM
Sound card
Video card

Types of software
Software - A set of instructions, stored digitally
within the computer's memory, which tells the computer system what  to do.
Software components of a computer system  have
no physical presence, they are stored in digital form within computer memory.
 There are different
categories of software, including  system
software, utilities and applications
software. Software can also be described as being either generic or bespoke.
System software is the software used to manage and control the
hardware components and which allow interaction between the hardware and the
other types of software. The most obvious type of system software is the
computer's operating system but device drivers are also included within
this category.
Utility software is software such as anti-virus software,
firewalls, disk defragmenters and so on which helps to maintain and protect the
computer system but does not directly interface with the hardware.
Applications
software (also
known as 'apps') are designed to allow the user of the system complete a
specific task or set of tasks. They include programs such as web browsers,
office software, games and so on. They are usually the reason you bought the
computer system in the first place and aren't concerned with the management or
maintenance of the system itself.
Any individual software package, whichever of
the above types it falls into, can be either generic (or 'off-the-shelf') or it can be bespoke(custom-built). Generic
software is mass produced with the intention that it will be used by a wide
variety of different users in a range of different situations. Bespoke software
is created for a specific purpose which will be used in a known environment.
Often generic software
is used when there is a package available that meets the needs of the user.
Because it is used by many more people the cost of creating it is spread over a
greater number of people or organisations and so the cost to the individual is
much lower. It also has the advantage that it is available immediately there's
no waiting time involved while the software package is designed, created and
tested. Bespoke software has the advantage that it can be tailor made to exact
specifications but it significantly more expensive and will take time to
create.

Telephoning
Vocabulary.
ü  telephone book
(directory) – телефонная книга
ü  telephone
booth (box phone) – телефон-автомат
ü  directory enquiries – телефонная служба
ü  switchboard operator – телефонист, оператор
ü  general call – общий звонок
ü  emergency call – экстренный звонок
ü  local call – местный звонок
ü  personal call – индивидуальный звонок
ü  IDD (international direct dialing) – прямой международный звонок
ü  to book (to
order) the call – заказать звонок
ü  to answer the
call – ответить на звонок
ü  to make a call
(to call, toRING up) – сделать звонок
ü  to call back
(to call later, to return the call) – перезвонить
ü  to misdial – неправильный звонок
ü  go ahead – разговаривать
ü  to hang up (to
ring off, to put down the receiver) – вешать трубку
ü  the line is
free(clear) – свободная линия
ü  to put down
(to write down) a telephone number – записать  номер телефона
ü  to speak more
loudly (to speak up) – разговаривать громко
Learning how to
communicate well on the telephone is one of the top priorities for many people
who need to use English at work. Learning the common phrases that are used on
the telephone helps us to know what to expect. Telephoning requires
special skills as there are a number of difficulties that arise when
telephoning that are specific to telephoning. The first and foremost difficulty
is not being able to see the person you are communicating with. This lack of
visual communication often makes people, who can communicate quite successfully
in other situations, nervous and thereby hinders their communicative abilities.
We do not telephone to someone. No
preposition is needed:
We make a phone  call
We dial a number
We contact someone by phone
We give someone a call
We give someone a ring
We telephone someone
We get hold of someone
We get in touch with someone
English business
telephone talks are clearly structured and strongly intended. According to
their intentions or purposes they can be easily classified into the following
general groups: giving information, requesting information, confirming
information, making arrangements, persuading the called party, negotiating and
complaining.
The most obvious thing is to plan your
telephone call; know the name of a person whom you want to speak to, and what
you want to say. The techniques of telephoning are very much the same in all
countries. Only remember your good telephone manners.
Advices
ü  When talking
on the telephone - speak clearly - Do not shout.
ü  Make sure that
your conversation with a busy person is as brief as possible.
ü  When you get a
wrong number don’t ask: “What number is this?” It is a good manner to ask: “Is
this two -three -four -five -six?” If not – apologize. If a wrong number call
comes through don’t lose your temper. Simply say: “Sorry, wrong number” – and
hang up.
ü  Always identify
yourself when making a call, especially if you are calling on business, e. g.
“This is Mr Brown of the British  Trade Mission. Could I speak to Mr Jones...”
ü  If you have a
visitor do not carry on a long chat your visitor tries hard to avoid listening
to your conversation. The best thing to do is to say you are busy at the
moment and ... “May I call you back in a little while?” But don’t forget to do
so.
Read and memorize the following words and
word-combinations. Be sure you understand the meaning of the words.

answer

to say "hello" into the phone
  when it rings

answering machine

something that you can record a message
  on if the person you are calling isn't home

busy signal

a beeping sound that tells the caller
  that the other person is already on the phone with someone else

call

a telephone conversation; to telephone

caller

the person who telephones

call back/phone back

to call someone who called you first

call display

a screen that shows you who is calling

cellular phone/cell phone

a telephone that you can take with you
  away from your house; mobile phone

dial

to press the buttons on the phone

dial tone

the sound the phone makes when you pick
  it up

directory/phone book

a book that alphabetically lists local
  phone numbers of people and businesses

hang up

to put the receiver down and end a call

operator

a person who answers telephone-related
  questions when you dial "0"

phone

a telephone; to telephone

phone booth/pay phone

a place where you can pay to use a
  telephone in public

pick up

to answer the phone

receiver

the piece on the phone that you speak
  into and listen from

ring

the sound a phone makes when somebody
  calls; to make that sound

ringer

the sound-piece that alerts a person
  that a call is coming through

Dialogue
Telephone conversation. Bad connection

- Hello. Pizza Delivery. Can I help you?
- Hi. Yes, I’ve been working all day and I am
really hungry.  Can I order a pizza, please?
- Sorry. Could you speak a bit louder, please? I
can’t hear you.
- Okay. I’d like to have a hot Pepperoni pizza,
please. Is your home delivery service free?
- I’m so sorry. I didn’t catch that again. Are
you going to have a pizza?
- Yes. That’s right, mam.
- Can you speak a little slower, please? Did you
say that you want a vegetarian pizza? Is that right?
- No, I didn’t. It’s strange but I can hear you
quite well.
- Oh, my god. There’s a lot of background noise
– I can barely hear you. And I’m struggling to understand. Well… Hang on one
second, please. I’ll go and turn off the radio.
- Sorry. What did you say? Will you speak up,
please?... Hello! … We seem to have a bad connection on this phone. Okay. I
think I have to choose someone else. Sorry about that anyway. Bye!
- Hello! … Apparently we got cut off.

Telephone conversation.

- Good afternoon. «Tower Investment Bank». May I
help you?
- Hi. I would like to talk to Mr. Clinton from
the accounting department, please.
- May I ask you who is calling?
- My name is Bruno Ponti. I’m calling from an
advertising agency.
- Thank you, Mr. Ponti. Just a moment, please.
Let me check if Mr. Clinton is in his office.
- Sure.
- Thank you for waiting. I’m sorry but Mr.
Clinton isn’t available at the moment. Would you like to leave a message or
shall I ask him to call you back? Does he have your number?
- I believe he does. But I can give it to you,
just in case.
- All right. Go ahead, please.
- My number is 046 78345.
- OK. And would you mind repeating your name?
- Sure. Bruno Ponti. I can spell it:
B-R-U-N-O  P-O-N-T-I.
- Thank you, Mr. Ponti. I’ll ask Mr. Clinton to
call you back as soon as possible today.
- Thanks a lot. Bye.

Batteries

Battery, in electricity and electrochemistry, any of a class of devices that convert chemical energy directly
into electrical energy. Although the term battery, in strict
usage, designates an assembly of two or more galvanic cells capable of such energy
conversion, it is
commonly applied to a single cell of this kind.
Every
battery (or cell) has a cathode, or positive
plate, and an anode, or negative plate.
These electrodesmust be separated by and are often immersed in anelectrolyte that permits the passage of ions between the
electrodes. The electrode materials
and theelectrolyte are chosen and arranged so that sufficien telectromotive force (measured in volts)
and electric current (measured in amperes) can be developed
between the terminals of a battery to operate lights, machines, or other
devices. Since an electrode contains only a limited number of units of chemical
energy convertible to electrical energy, it follows that a battery of a given
size has only a certain capacity to operate devices and will eventually become
exhausted. The active parts of a battery are usually encased in a box with a
cover system (or jacket) that keeps air outside and the electrolyte solvent
inside and that provides a structure for the assembly.
Commercially available
batteries are designed and built with market factors in mind. The quality of
materials and the complexity of electrode and container design are reflected in
the market price sought for any specific product. As new materials are
discovered or the properties of traditional ones improved, however, the typical
performance of even older battery systems sometimes increases by large
percentages.
Batteries
are divided into two general groups: (1) primary batteries and (2) secondary, or storage, batteries. Primary batteries
are designed to be used until the voltage is too low to operate a given device
and are then discarded. Secondary batteries have many special design features,
as well as particular materials for the electrodes, that permit them to be
reconstituted (recharged). After partial or complete discharge, they can be
recharged by the application of direct current (DC) voltage. While the original state is usually not
restored completely, the loss per recharging cycle in commercial batteries is
only a small fraction of 1 percent even under varied conditions.

Cellphone
The history
of mobile phones, covers mobile communication devices which
connect wirelessly to the public switched telephone network.
While the transmission of speech by
radio has
a long history, the first models that were wireless, mobile, and also capable
of connecting to the standard telephone network are much more recent. The first
such devices were barely portable compared to today's compact hand-held
devices, and their use was clumsy.
Along with the process of developing more
portable technology, and better interconnections system, drastic changes have
taken place in both the networking of wireless communication and the prevalence
of its use, with smartphones becoming common globally and a growing
proportion of Internet access now done via mobile broadband.
In December 1947, Douglas H. Ring and W. Rae Young, Bell Labs engineers, proposed hexagonal cells for mobile phones in vehicles. At this stage,
the technology to implement these ideas did not exist, nor had the frequencies
been allocated. Two decades would pass before Richard H. Frenkiel, Joel S. Engel and Philip T. Porter of Bell Labs expanded the early proposals into
a much more detailed system plan. It was Porter who first proposed that the
cell towers use the now-familiar directional antennas to reduce interference
and increase channel reuse (see picture at right)  Porter also invented the
dial-then-send method used by all cell phones to reduce wasted channel time.
In all these early examples, a mobile phone
had to stay within the coverage area serviced by one base station throughout
the phone call, i.e. there was no continuity of service as the phones moved
through several cell areas. The concepts of frequency reuse and handoff, as well as a number of other concepts that formed the
basis of modern cell phone technology, were described in the late 1960s, in
papers by Frenkiel and Porter. In 1970 Amos E. Joel, Jr., a Bell Labs engineer, invented a "three-sided trunk
circuit" to aid in the "call handoff" process from one cell to another. His patent
contained an early description of the Bell Labs cellular concept, but as
switching systems became faster, such a circuit became unnecessary and was
never implemented in a system.
A cellular telephone switching plan was
described by Fluhr and Nussbaum in 1973, and
a cellular telephone data signaling system was described in 1977 by Hachenburg
et al.

FAX

Fax, in
full facsimile,
also called telefax,
in telecommunications, the transmission and reproduction of documents by wire or
radio wave. Common fax machines are designed to scan printed textual and graphic
material and then transmit the information through the telephone network
to similar machines, where facsimiles are reproduced close to the form of the
original documents. Fax machines, because of their low cost and their
reliability, speed, and simplicity of operation, revolutionized business and
personal correspondence. They virtually replaced telegraphic services,
and they also present an alternative to government-run postal services and private
couriers.

STANDARD FAX TRANSMISSION
Most office and home fax
machines conform to the Group 3 standard, which was adopted in 1980 in order to
ensure the compatibility of digital machines operating through public telephone
systems worldwide. As a standard letter-size sheet is fed through a machine, it
is scanned repeatedly across its width by a charge-coupled device (CCD), a solid-state scanner that has 1,728 photosensors in a single row. Each photosensor in turn generates a low
or high variation in voltage, depending on whether the scanned spot is black or
white. Since there normally are 4 scan lines per mm (100 scan lines per inch),
the scanning of a single sheet can generate almost two million variations in
voltage. The high/low variations are converted to a stream of binary digits, or bits,
and the bit stream is subjected to a source encoder, which reduces or “compresses” the number of bits
required to represent long runs of white or black spots. The encoded bit stream
can then be modulated onto an analogcarrier wave by a voice-band modem and
transmitted through the telephone network. With source encoding, the number of
bits required to represent a typewritten sheet can be reduced from two million
to less than 400,000. As a result, at standard fax modem speeds (up to 56,000
bits per second, though usually less) a single page can be transmitted in as
little as 15 seconds.
·

Communication between a transmitting and a receiving fax machine opens with the dialing of the telephone number of the
receiving machine. This begins a process known as the “handshake,” in which the
two machines exchange signals that establish compatible features such as modem speed, source code, and printing resolution. The page information
is then transmitted, followed by a signal that indicates no more pages are to
be sent. The called machine signals receipt of the message, and the calling
machine signals to disconnect the line.
At the receiving machine, the
signal is demodulated, decoded, and stored for timed release to the printer. In
older fax machines the document was reproduced on special thermally sensitive
paper, using a print head
that had a row of fine wires corresponding to the photosensors in the scanning
strip. In modern machines it is reproduced on plain paper by a xerographic
process, in which a minutely focused beam of light from a semiconductor laser or
a light-emitting diode,
modulated by the incoming data stream, is swept across a rotating,
electrostatically charged drum. The drum picks up toner powder in charged spots
corresponding to black spots on the original document and transfers the toner
to the paper.
·

Негізгі әдебиет
1.
 «Английский язык для студентов» И. П. Агабекян
Ростов-на-Дону «Феникс» 2012 г
2.
Eric H.
Glendinning, John McEvwan. Oxford English for Electronics.  Oxford University
Press.
3.
English for
telephoning David Gorden Smith  Oxford Business English.
4.
Толмачева Л.Ф.Учебное
пособие по английскому языку для студентов транспортных ВУЗов Изд-во «Бастау».
г. Алматы, 2001 г.
5.
Raymond
Murphy «English Grammar in Use» Second edition Cambridge University Press
6.
Ю. Голицынский «Грамматика Сборник упражнений»
«Каро» 2006 г.
7.
И. П. Агабекян
«Английский язык» 20 издание Ростов-на-Дону «Феникс» 2012 г
8.
И. П. Агабекян «Английский язык»
20 издание Ростов-на-Дону «Феникс» 2012 г

Қосымша әдебиет
1.
«Англо-русский словарь
сокращений по телекоммуникациям» А. В. Александров «Руссо»  Москва
2002 г
2.
В.К. Мюллер
«Англо-русский  Русско-английский словарь» Москва,2009 г.
3.
Д. Коллин «Англо-русский русско-английский словарь с
грамматическим приложением» Москва «Ладком» 2012 г.
4.
Л. Д. Цесарский «After lessons» Пособие по Английскому языку для внеаудиторных
занятий для средних специальных учебных заведений Москва «Высшая школа» 2001 г.

5.
В. Франк, А. Досмаганбетова «Қазақ тілі»  жоғарғы
сынып оқушылары және студенттерге арналған
анықтамалық. Алматы, 2006 ж.

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alt: Тақырып 2.3. Компьютердің шығу тарихы

alt: Differences old and new phones

alt: Theme 1.8 . Radio transmitters

alt: Theme 4.3. Transistor characteristics

alt: Test (Grammar and lexical themes)

alt: Мазмұны Кіріспе .........

alt: The Republic of Kazakhstan.

alt: Peaceful and generous, the land of the

alt: Communication system Topical vocabulary

alt: About communıcatıon system of

alt: Dialogue Woman 1: Hello, Mrs

alt: May 7 is celebrated in our country as

alt: A "radio receiver" is an electronic circuit that receives its input from an antenna , uses electronic filters to separate a wanted radio signal from…

alt: Lowest frequency in a complex waveform

alt: Resistance of a load. logic -

intro: Учебно-методический комплекс ориентированный на железнодорожных специальности.  Учебно методический комплекс включает в себя лексические материалы по темам.  Отличное пособие для данных специальностей.  Лексические материалы для специальности: "Оптическое и электронное оборудование". Состоит из  10 разделов, который включает разные технические темы. Приятного пользованияУчебно-методический комплекс

английский язык

group: Дисциплины

title: УМК для всех железнодорожных специальностей по предмету "Профессиональный английский язык"