Tiếng anh chuyên ngành điện tử Unit 1: electronics in the home IC: integrated circuits CD: compact disc Hi-fi: high fidelity Task 6: An aerial is an electrical device which converts electric power into radio waves or converts radio waves into electric power. The tuner selects the required signal. The detector seprate off the audio part of the signal. The AF amplifier amplifies signal. The volume control adjusting the sound level. The power amplifier amplifies low-power audio signals. The speaker produces sound. Task 7: cấu trúc The radio consists of/is composed of a tuner,a detector,and an AF amplifier. The tuner connected to/is linked to the detector. Task 11: Fig. 3 shows the block diagram 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 it 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 AF signal to modulate the RF carrier wave.The power of modulated carrier wave is increased by the RF power amplifier. The strong modulated output signals are fed to the aerial which enables them to be transmitted over long distances. Unit 5 : batteries Task 5: cau truc : It is called/is known as a NiCad cell Task 6: describe their function (hoc thuoc) 1.It is called a resistor .it adds resistance to a circuit 2.It ia called a variable resistor.it varies the circuit in a circuit 3.It is called transformer.it is steps AC voltages up or down 4.It is called sigalpole.it breaks a circuit 5. It is called diode .it rectifies alter nating current 6.It is called volmeter.it measures voltages 7.It is called variable capacitor.it varies capacitance in a circuit 8.It is called a fuse.it protects a circuit 9.It is called miliammeter.it measures very small currents 10.It is called aerial.it receives RF signals Task 8(thuoc) Verb Noun Verb Noun Record recorder oscillate oscillator Transmit transmitter transform transformer Charge chargger rectify rectifier Process processor amplify amplifier Collect collector detect detector Tune tuner Task 10:write sentence present the functions of the following component/units battery changer: 1. The transformer steps down the AC mains voltage 2.The double pole switch switches the charger on and off 3.The neon lamp shows when the load varies 4.The fuse protects the transformer 5.The retifier converts the AC voltage to a DC voltage 6.The aluminium heartsink keeps the diodes from overhearting 7.The smoothing circuit prevents the output from changing when the load varies 8.The stabilizing circuit removes the fluctuations in the DC output of the rectifier Uint 6:making a recording Task 1: (hoc thuoc) A: The musicans play in a recording studio. Each voice and instrument is recorded using different microphones. B: Each microphone input is mixed on a mixer. In a commercial recording studio this is done by a sound engineer. C: The instrucments are channelled through the mixer into a multitrack tape recorder. D: The sounds on the multitrack are remixed until the musicans are happy with the sound. E: During this process, effects, such as reverb, are used to shape the sound. F: The output is recorded on a two-track mastering machine. The product is a master tape with two stereo channels Task 6: Describing a process Firstly, a blank perpex disc is grinded and polished to optical flatness. Next, it is washed and spin-dried. It is then coated with a thin layer of photorestist and cured in an oven. After that, as the disc is revolved, a laser beam is used to mark the audio information parttern on its surface. This process is know as ‘cutting’ the disc. The photorestist is then developed and etched to produce pits in the disc’s surface. These pits represent the digital audio pattern. The disc is then given a thin silver coat to make it electrically conductive. Next, Electroplanting is use to make a series of positive and negative copies of the master disc. The final negative copy is used to made a large number of identical CDs. The surface of the CD containing the pit marks is then coated with a 10mmlayer of aluminium followed by a protective layer of plastic. After punching the centrer hole, a lable is applied and the CD is packaged. Unit 9:alarm systems Task 3: Door switch Window foil Pressure mat Passive infra-red detector Detection devices Magnetic switches: These are used on windows and doors. A magnet mounted on the moving part of the window or door trips a switch mounted on the frame when the window or door is opened. Break detectors: These are fitted on the inside surface of glass in windows and doors. Some use a thin metal foil which is glued around the edge of the glass: if the glass is broken the foil breaks too. Others are vibration sensors, and respond to the shock of the glass being broken. Pressure mats: These are fitted under the carpet-at the bottom of the stairs, for example. The pressure of someone stepping on them causes two thin metal plates inside to come in contact, setting off alarm. Because they’re constantly being walked on, pressure mats can get ‘tired’ quite quickly, and should be regularly tested and replaced if necessary. Motion sensor: These may use passive infra-red, ultrasonic, or microwave energy to detect movement within their range. Task 5:in a simple alarm circuit what is the consequence of each action bellow? 1.A burglar disconnects the supply ,the alarm continues to operate on batteries 2.The glass is broken, the foil breaks too 3.A door is opened, a magnet on the door trips a switch on the frame 5.You are not there to reset the system ,the alarm stops after a set time 6.A burglar tries to force the alarm open, tamper sensors trigger the alarm 7.Someone steps on them, two thin metal plates come in contact. Task 8: Integrated circuit remote control Zener diode Circuit diagram reed switch reverse bias Alternating current surface wave mains supply Primary cell vibration sensor Unit 10:radio Task 1: Gamma rays – X rays – ultraviolet rays – visible light – infra red rays – radio waves. Task 2,3: surface wave sky wave space wave Frequencies low below 30 MHz VHF,UHF Travels along the ground skywards space Range about 1500km thousand of up to 150km kilometres is possible on earth Difficulties energy is absorbed air molecules hills, buildings from it by the ground or trees. Task 11: 1.Aerial receives weak RF signals 2.RF tuner selects the required RF wave from those picked up by the aerial 3.RF amplifier amplifies the selected RF wave 4.Detector separates the audio modulation from the RF carrier wave 5.AF amplifier amplifies the audio signal to make is strong enough to drive the loudspeaker 6.Loudspeaker converts the audio signal into sound Unit 15: drum machine Task 2: 1, When then drum pad is pressed, the stored information is decoded and produces an electronic signal 2, The signal is sliced into many ’samples’, each one a snapshot of the strength of the signal at one particular moment. This information is converted into binary code and then stored in the machine’s memory 3, When the drum is hit, it produces sound waves 4, The signal is turned into sound waves through an amplifier, and the drum sound is heard 5, The sound waves reach the microphone and are converted into an electrical signal. Task 5: 1, With a drum machine, you can play any drum sound by pressing the right button 2,You can create drum music without playing a drum 3,What we hear as sound are changing in air pressure 4,These are converted to electrical signals by using a microphone 5,The information contained in the drum machine memory consists of samples of these electrical signals 6,A drum machine contains record of sound taken at measured intervals 7,This process is called sampling 8,The functions of a drum machine include panning and tuning 9,Panning means the positing of the drum sound in stereo Task 6: 1,A burglar alarm = alarm which warns burglar 2, A clock timer = a timer for use in a clock 3,A mercury switch = a switch which uses the movement of mercury 4,A car phone = a phone for use in a car 5, A germanium diode = a diode which contains germanium 6,A ground wave = a radio wave which travels along the surface of the earth 7,A block diagram= a drawing showing the different electronic stages which make up a circuit 8,An assembly line = a production area of a factory where the parts of a product are put together in a series of stages 9,A fuseholder = a device worn on the head which covers each ear with a small loudspeaker 10,A wavemeter = an electric instrument for measuring the frequency of a transmitter singal 11,A cell phone = a cellular phone 12,Head phones = a device worn on the head which covers each ear with a small loudspeaker 13,An ammeter = an electronic instrument for measuring current 14,A handset = an electronic device which can be held in one hand Unit 16:audio recording systems Task 1: LP: long playing record CD: compact disc Task 3: LPs CDs 1 Recording system analogue digital 2 Sound quality poorer than the original near-perfect than the original 3 Access serial random 4 Audio pattern groove pits 5 Material vinyl perspex 6 Playing mechanism mechanical laser optical 7 Durability easily damaded high durablity 8 Size 12 inches 12cm 9 Playing time 45 minutes 74 minutes Task4: 1,Distortion to high a recording level 2,Noise generated within components poor recordings 3,Overheating a transistor is damage 4,Dirty heads scratches on records 5,A build up of oxide on the head is the tape rubbing against the head 6,Jumping is hiss 7,Unwanted signals interference on radios Unit 18:graphs Task 1:Sales of sigles …… rose or decrease (Slightly, Gradually, Steady, Steep, Sharp, Sudden, Fast) Task 5: 1,Computers process data 2,You can record sound on tape or disc 3,A bridge circuit is used to rectify alternating current to produce direct current 4,All metals, and some non metals such as carbon, conduct electricity 5,To prevent radio interference ,you must dissipate any sources of interference such as car ignition systems 6,Power transistors emit heat. Therefore they must be mounted on a heatsink 7,The electron gun in a CRT conduct a stream of electrons 8.When recording a CD, sound is sample 44100 times every second Unit 19:test and repair instruments Task 3: Multimeter : This instrument can be used to measure a number of different electrical quantities, such as voltage, current, and resistance, i.e. it is a combined voltmeter, ammeter, and ohmmeter. Multimeters can have analogue or digital displays and can be switched to different measuring ranges. Logic probe : This instrument is used for measuring voltage levels and pulses in digital logic circuits. When the probe is placed on the pin of a logic IC, small colored LEDs light up to indicate if a pulse is detected or whether the pin is at a high or a low logic level. Oscilloscope : This instrument is used to measure fast-moving signals. It shows how a signal varies with time or relative to another signal. It uses a cathode ray tube to display the waveform of the measured signal on a screen. Function generator : This instrument contains a triangular wave oscillator which can be switched to produce triangular, square, or sine waves over a range of frequencies. It is used to test and adjust a variety of electronic equipment such as audio amplifiers. The function generator provides a known signal which can be injected into a circuit. Often it is used with an oscilloscope so that a visual display of the waveform can be seen. Task 5: Cathode ray tube Televisions as well as computers, radar systems, and oscilloscopes use a cathode . Tiếng anh chuyên ngành điện tử Unit 1: electronics in the home IC: integrated circuits CD: compact disc