Type of modulation of the main carrier.

 

4                   

Nature of signal(s) modulating the main carrier.

 

 

Вопрос 18

Ionospheric layers reflect following radio frequencies:

 

 

Ответы

1                   

VHF

 

2              

HF

 

3                   

UHF

 

4                   

SHF

 

 

Вопрос 19

VLF (Very Low Frequency) waves appear in the frequency spectrum:

 

 

Ответы

1              

KHz-30 KHz

 

2                   

300 MHz-3000 MHz

 

3                   

3 GHz-30 GHz

 

4                   

30 MHz-300 MHz

 

 

Вопрос 20

The wavelength of a non-directional beacon (NDB) at a frequency of 400 kHz is:

 

 

Ответы

1                   

150 metres

 

2              

Metre

 

3                   

1000 metres

 

4                   

10 metres

 

 

Вопрос 21

An electromagnetic wave consists of an oscillating electric field (E) and an oscillating magnetic field (H). Their propagation speed is

 

 

Ответы

1                   

the speed of light for field E and the speed of sound for field H.

 

2              

The speed of light.

 

3                   

the speed of sound for field E and the speed of light for field H.

 

4                   

the speed of sound.

 

 

Вопрос 22

The phenomenon of a change in direction of a radio wave occurring due to a change in its speed is called?

 

 

Ответы

1                   

reflection

 

2                   

diffraction

 

3                   

interference

 

4              

Refraction

 

 

Вопрос 23

Which of the following is true with reference to frequency of a radio wave?

 

 

Ответы

1                   

Frequency is the minimum number of cycles occurring in one minute in a radio wave expressed in Hertz (Hz).

 

2              

Frequency is the number of cycles in one second in a radio wave expressed in Hertz (Hz).

 

3                   

Frequency is the length of a radio wave expressed as an angle.

 

4                   

Frequency is the maximum deflection in a radio wave expressed in Hertz (Hz).

 

 

Вопрос 24

EHF (Extremely High Frequency) waves appear in the frequency spectrum:

 

 

Ответы

1                   

3 MHz-30 MHz

 

2                   

30 MHz-300 MHz

 

3                   

3 GHz-30 GHz

 

4              

GHz-300 GHz

 

 

Вопрос 25

Skywaves originate from which physical phenomenon called?

 

 

Ответы

1                   

diffraction

 

2              

Refraction

 

3                   

absorption

 

4                   

interference

 

 

Вопрос 26

VHF (Very High Frequency) waves appear in the frequency spectrum:

 

 

Ответы

1              

To 300 MHz range.

 

2                   

3 to 30 MHz range.

 

3                   

3 to 30 kHz range.

 

4                   

30 to 300 kHz range.

 

 

Вопрос 27

The wavelength of a radio signal with a frequency of 124.95 MHz is:

 

 

Ответы

1                   

24,6cm

 

2                   

2,40cm

 

3              

M

 

4                   

2,46m

 

 

Вопрос 28

In aviation electronic systems the so-called Doppler principle may be used in:

 

 

Ответы

1                   

VOR, DME and ILS.

 

2              

VOR, GPS and MTS and the turbulence mode of AWR.

 

3                   

VOR, MTI and the mapping mode of AWR.

 

4                   

VOR, DME and GPS.

 

 

Вопрос 29

Which of the following terms describes the maximum deflection in an oscillation?

 

 

Ответы

1                   

period

 

2                   

phase

 

3              

Amplitude

 

4                   

frequency

 

Вопрос 30

UHF (Ultra High Frequency) waves appear in the frequency spectrum:

 

 

Ответы

1                   

30 MHz-300 MHz

 

2              

MHz-3000 MHz

 

3                   

3 MHz-30 MHz

 

4                   

3 GHz-30 GHz

 

 

Вопрос 31

The frequency which corresponds to a wavelength of 1 mm is:

 

 

Ответы

1              

GHz

 

2                   

30 GHz

 

3                   

0,3 GHz

 

4                   

3,0 GHz

 

Вопрос 32

At a height 6000 feet you might expect to receive a VHF signal, from a VDF facility transmitter located at sea level,

 

at a range of:

 

 

Ответы

1              

NM

 

2                   

87 NM

 

3                   

95 km

 

4                   

86 km

 

 

Вопрос 33

In flight, a pilot can improve the range of his transmission with a VDF operator by:

 

 

Ответы

1                   

flying out of clouds.

 

2                   

speaking louder.

 

3              

Increasing altitude.

 

4                   

decreasing altitude.

 

 

Вопрос 34

Abbreviation VDF means:

 

 

Ответы

1                   

Very Direct Finder.

 

2                   

Very High Frequency Deviation Finding Station.

 

3                   

Variable Direction Finder.

 

4              

VHF Direction Finder.

 

Вопрос 35

Range of VDF depends on:

 

1) Loudness of the voices of the pilot and the operator when transmitting.

 

2) Power of pilot voice when transmitting.

 

3) Aircraft altitude and ground transmitter elevation.

 

4) Power of airborne and ground transmitters.

 

The combination regrouping all the correct statements is:

 

 

Ответы

1              

3,4

 

2                   

1

 

3                   

2,4

 

4                   

2

 

 

Вопрос 36

Range of VDF depends on:

 

1) Line of sight formula.

 

2) Power of transmitters.

 

3) Intervening high ground.

 

The combination regrouping all the correct statements

 

 

Ответы

1                   

1,3

 

2              

1,2,3

 

3                   

1,2

 

4                   

2

 

 

Вопрос 37

What is the "Q" code for a magnetic bearing from a VDF station?

 

 

Ответы

1                   

QDM.

 

2                   

QTE.

 

3                   

QNH.

 

4              

QDR.

 

 

Вопрос 38

What airborne equipment, if any, is required to be fitted in order that a VDF let-down may be flown?

 

 

Ответы

1                   

VOR/DME.

 

2              

VHF radio.

 

3                   

None.

 

4                   

VOR.

 

 

Вопрос 39

Which of the following is an advantage of Ground/DF (VDF) let-down?

 

 

Ответы

1                   

It is pilot interpreted and does not require the assistance of АТС.

 

2              

It only requires a VHF radio to be fitted to the aircraft.

 

3                   

It does not require any special equipment, apart from a VHF radio, to be installed in the aircraft or on the ground

 

4                   

It does not require any special equipment to be fitted to the aircraft.

 

Вопрос 40

The VDF class С bearing is accurate to within:

 

 

Ответы

1              

±10°

 

2                   

±15°

 

3                   

±2

 

4                   

±5°

 

 

Вопрос 41

What is the "Q" code for a true bearing to a VDF station?

 

 

Ответы

1                   

QDM

 

2              

QUJ

 

3                   

QTE

 

4                   

QDR

 

 

Вопрос 42

What is the effect of multipath signals (coming from the same aircraft) at the Ground VHF Direction Finder

 

station?

 

 

Ответы

1                   

It may result in an increase of the distance at which the Ground VHF Direction Finder station receives signals from the aircraft, if the Ground Station is situated in the skipzone.

 

2                   

It reduces the range at which the Ground VHF Direction Finder station receives signals from the aircraft.

 

3                   

Regardless the difference in distance travelled by these signals, it results in their extinction of the signals at the Ground VHF Direction Finder station.

 

4