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Electronics in the home D8-DTVT2 Group : 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 on page 188 to help you - IC : integrated circuit CD: Compact dics Hi- Fi: (high fidelity) Task : 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, lowpowered 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 : Fill in the gaps in this table with the help of the text Date Early 20 century 1947 1958 Future th Invention Vacuum Tube Transistor Microelectronics robot Application in the home Radio, TV, Record players Hi-Fi units, portable radios Automatic washing- machines Computer controlled robots Task : 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 : Read the text below to find the answers to these questions: What we call the two types of diagrams shown in the text? Block diagrams and Circuit diagrams What we call the approach to electronics which focuses on the function of units? Systems approach to electronics Task : How many of the circuit symbols in Fig.2 can you identify? Use Appendix 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 :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 Prefix Giga Mega Kilo Deci Milli Micro Nano Pico Symbol G M K D M µ N p Mutiple 10 106 103 10-1 10-3 10-6 10-9 10-12 Example GHz gigahertz MΩ megohms kV kilovolts dB decibels mW milliwatts µH microhenries nF nanofarads pF picofarads 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 : 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 What is the diagram of? What does it consist of in terms of blocks? How are the blocks connected? What is the funcion of each block? 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  ... kilohm resistor 2, C1 (5-65 pF) A five-to-sixty-five-picofarad capacitor 3, R3 (47 K) A Forty-seven kilohm resistor 4, C3 (10 uF) a ten-microfarad electrolytic capacitor 5, P1 (5K) a five-kilohm... developed (X) Task : Fill in the gaps in this table with the help of the text Date Early 20 century 1 947 1958 Future th Invention Vacuum Tube Transistor Microelectronics robot Application in the home... recorders These devices were large and use a lot of power (X) The invention of the transistor on 1 947 meant that much smaller, lowpowered devices could be developed A wide variety of electronic devices