ĐIỆN tử VIỄN THÔNG DTVT2 nhom3 bai6 khotailieu

Television Task 2 : Surface wave Frequencies tần số Low frequency long waves Travels đường truyền Along the ground Range khoảng cách About 1500km Difficulties khó khăn Absorbed by the gr

Radio

Task 1 :

1 Television

Task 2 :

Surface wave Frequencies (tần số) Low frequency (long waves)

Travels (đường truyền) Along the ground

Range (khoảng cách) About 1500km

Difficulties (khó khăn) Absorbed by the ground

Task 3 :

Sky wave Space wave Frequencies (tần số) below 300MHz VHF, UHF

Travels (đường truyền)

Skywards and returned to earth by the ionosphere

line of sight transmission

Range (khoảng cách) Hàng nghìn km 150km

Difficulties (khó khăn) attenuated by refraction hills, buildings, or trees

Task 4 :

1 A Transmitting aerial

2 E Surfaca wave

3 D Space wave

4 C Sky wave

5 B Receiving aerial

Task 5 :

1 When the switch is closed, current flows through the primary of the

transformer

2 On being reflected, the radar signal trikes a plane

3 When a cell discharges quickly, it may become hot

4 On following your instructions, the TV receives signal from the remote control

5 On being compared with the transmitted signal, the radar receiver receives the reflected signal

6 When choosing a course in electronics, you think carefully about your future

7 On being deflected, microwave signals strike a high building

8 When making a recording, you should ensure the recording levels are

satisfactory

9 On triggering an audible warning, the alarm detects an intruder

10 When the remote control button is pressed, the television set changes channel

Task 7 :

Verb Noun (component) Noun (property)

Task 9:

1 AF- Audio frequency

2 RF- Radio frequency

3 AM- Amplitude modulated

4 FM- Frequency modulated

Task 10:

a RF carrier

b AF signal

c AM carrier

d FM carrier Task 11: