ĐIỆN tử VIỄN THÔNG DTVT2 nhom3 bai6 khotailieu
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DTVT2.Nhom3.Bai6
Radio
Task 1 :
1. Television
Task 2 :
Frequencies (tần số)
Travels (đường truyền)
Range (khoảng cách)
Difficulties (khó khăn)
Surface wave
Low frequency (long waves)
Along the ground
About 1500km
Absorbed by the ground
Task 3 :
Sky wave
Space wave
Frequencies (tần số)
below 300MHz
VHF, UHF
Skywards and returned to
earth by the ionosphere
Travels (đường truyền)
line of sight transmission
Range (khoảng cách) Hàng nghìn km
150km
Difficulties (khó khăn) attenuated by refraction hills, buildings, or trees
Task 4 :
1.
2.
3.
4.
5.
A. Transmitting aerial
E. Surfaca wave
D. Space wave
C. Sky wave
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
Absorb
Attenuate
Communicate
Conduct
Induct
Modulate
Reflect
Resist
Task 9:
1.
2.
3.
4.
AF- Audio frequency
RF- Radio frequency
AM- Amplitude modulated
FM- Frequency modulated
Task 10:
a.
b.
c.
d.
Task 11:
Noun (component)
Absorber
Attenuator
Communicator
Conductor
Inductor
Modulator
Reflector
Resistor
RF carrier
AF signal
AM carrier
FM carrier
Noun (property)
Absorption
Attenuation
Communication
Conductivity
Induction
Modulation
Reflection
Resistance
