ĐIỆN tử VIỄN THÔNG nhóm 4 khotailieu

You can use Appendix 1 on page 188 to help you - IC : integrated circuit - CD: Compact dics - Hi- Fi: high fidelity Task 3 : Read quickly through the text on the next page.. The introduc

Electronics in the home

D8-DTVT2

Group 4 :

Ngô Đắc Quân

Lê Văn Hoạch

Phùng Thế Quảng

Phạm Thị Minh Phượng

Nguyễn Thị Phương

Ngô Thị Phượng

Nguyễn Nhật Thư

Nguyễn Tuấn Anh

Task 1: Make a list of things in your home which use electronics Compare your list with that of another group

- Television

- Door bell

- Lamp

- Air Condition

- Fan

- Laptop

- Dryer

- Speakers

- Radio

- Smart Phone

- Washing-machine

Task 2: Find out the meaning of these abbreviation You can use Appendix 1 on page 188 to help you

- IC : integrated circuit

- CD: Compact dics

- Hi- Fi: (high fidelity)

Task 3 : Read quickly through the text on the next page Tick (x) any item mentioned in the list you made in task.

- Electronics began at the start of twentieth century with the invention of the vacuum tube The first devices for every day use were radios,

followed by televisions, record players, and tape recorders These

devices were large and use a lot of power (X)

- The invention of the transistor on 1947 meant that much smaller, low-powered devices could be developed A wide variety of electronic

devices such as hi-fi units and portable radios became common in the

home (X)

- It was not until 1958 that microelectronics began with the development of Ics (integrated circuits) on silicon chips This led to a great increase in the use of electronics in everyday items The introduction of the

microprocessor allowed electronics of the microprocessor allowed

electronics to be used for the control of many common processes

- Microprocessors are now used to control many household items such as automatic washing-machines, dishwashers, central heating systems, sewing machines and food processors Electronics timers are found in digital alarm clocks, water heaters, electric cookers and microwave ovens Telephones use electronics to provide automatic dialing and answerphone facilities New entertainment devices have been

developed, such as video recorders and CD (Compact disk) player (X)

- In the future, electronics are likely to become even more common in the home as multimedia entertainment systems and computer controlled

robots are developed (X)

Task 4 : Fill in the gaps in this table with the help of the text

Early 20th century Vacuum Tube Radio, TV, Record players

1947 Transistor Hi-Fi units, portable radios

1958 Microelectronics Automatic washing- machines Future robot Computer controlled robots

Task 5 : Use the space below to make a list of ways in which you think electronics may be used in the home in the future.

- Electonics car

- Robot

- Smart house controlled by smart phone

- Multimedia entertainment systems

- Door Automatic: open/ close

- Lamp Automatic:turn on/ turn off in the home

- Smart house controlled by voice

- Smart watch

- Electronics pen

- Electronics glasses

Reading Understanding diagrams

In electronics, you have to read not only texts, but also diagrams You have to be able to combine information from both diagram and text This text introduces two kinds of diagrams often used in electronics.

Task 6 : Read the text below to find the answers to these questions:

1 What do we call the two types of diagrams shown in the text?

Block diagrams and Circuit diagrams

2 What do we call the approach to electronics which focuses on the function of units?

Systems approach to electronics

Task 7 : How many of the circuit symbols in Fig.2 can you identify? Use Appendix 2 on page 206 to help you.

Language study Describing block diagrams and circuits

Look again at Fig.1 above We can describe it like this:

The radio consists of A tuner, a detector, and an AF amplifier.

is composed of

Using comprise, we can start our description with the blocks:

A tuner, a detector, and an AF amplifier comprise the radio.

We can describe the links between each building block using these

expressions:

The tuner is connected to the detector.

is linked to

Look again at Fig.2 We can describe the values of the components like this:

R1 : a two-hundred-and twenty-kilohm resistor (220K)

C2 : a hurdred-picofarad (puff) capacitor (100pF)

Task 8 :Describe the value of these components

1, R2 (1K) A one kilohm resistor

2, C1 (5-65 pF) A five-to-sixty-five-picofarad capacitor

3, R3 (47K) A Forty-seven kilohm resistor

4, C3 (10 uF) a ten-microfarad electrolytic capacitor

5, P1 (5K) a five-kilohm potentiometer (POT)

6, L1

This table provides the terms you need.

Looking now at the basic units of the circuit, we can describe the

volume control like this:

The volume control consists of a ten-microfarad electrolytic capacitor connected in serial with a five-kilohm potentiometer (POT) The positive terminal of the

capacitor is connected to output of the AF amplifier and the wiper of the pot is connected to power amp The third terminal of the pot is connected to the zero voltage supply rail, which is earthed

Task 9 : Fill in the gaps in this description of the tuned circuit shown

in Fig.2 Each gap represents one word.

The circuit consists of a four hundred and seventy microhenry inductor which is connected in parallel with a variable capacitor The capacitor can be varied

between five and sixty-five picofarad The aerial is connected to the top end of the tuner It is also connected to the positive terminal of the diode in the detector The bottom end of the tuner is connected to earth via the zero voltage supply rail.

Speaking Practice

Task 10: Work in pairs

Task 11: Writing Describing diagrams

With the help of the diagrams, fill in the gaps in the description on page 12 Each gap represents one word The description should answer these questions

Fig.3 shows the block diagrams of an amplitude-modulated (AM) radio transmitter

It consists of a radio frequency (RF) oscillator, a modulator, an audio frequency (AF) amplifier, and an RF power amplifier The RF oscillator generates an Rf

carrier wave which is fed into the modulator.

The microphone converts sounds into audio frequency signals which are amplified

by the AF amplifier The modulator then uses the amplified AFsignals to

modulator the RF carrier wave

The power of the modulated carrier wave is increase by the RF poweramplifier The strong modulated output signals are fed to the aerial which enables them to be

transmitted over long

distances