Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ELEC 310 > Mod 9-10-11-12 > Flashcards

Mod 9-10-11-12 Flashcards

1
Q

What is the range of operating frequencies for VHF com systems on an aircraft?

A

118.000 MHz to 135.975 MHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the purpose of the ‘test’ switch on a VHF com control panel?

A

To disable the squelch circuit, allowing the background noise to be heard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When adjusting the squelch control on a VHF com system, why is it important to NOT turn the squelch too far past the point where the noise disappears?

A

It may cause a weak station to not be received

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which of the following radio circuits is NOT part of the receiver function of an aircraft VHF com radio?

A

Compression circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which of the following specifications for receiver sensitivity would provide the greatest range (distance between transmitter and receiver), while still allowing a signal to be heard?

A

2 µV, for 6 dB S/N ratio

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which type of antenna is used with an aircraft VHF com system?

A

A ¼ wavelength vertically polarized antenna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How much of an increase in transmitter output power would be required in order to double the range?

A

4 times the power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the effective range of a VHF com transceiver on an aircraft that is flying at 4500 feet above ground level (AGL)?

A

73.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the range of operating frequencies for aircraft HF?

A

2.0 MHz to 30 MHz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which of the following components is used in an aircraft HF system but not in an aircraft VHF com system?

A

antenna coupler

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which control in an HF system is used to fine-tune the frequency of the received audio signal?

A

Amplitude Modulation (AM) and Single Side Band (SSB)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which method of propagation is primarily utilized by an aircraft HF system?

A

sky wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which antenna location identified by the lettering on the photo above is the HF antenna?

A

D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When an HF system is first keyed after tuning to a new frequency, a tone is heard on the headset for approximately 10 seconds. What does the presence of the tone indicate?

A

That the antenna coupler is matching the antenna to the selected frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Aircraft HF communications systems are used for long-range communications in remote areas and for trans-oceanic operations.

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The reliability of HF communications is highly dependent on the conditions presented by the troposphere.

A

no

17
Q

Which of the following best describes the purpose of a SELCAL system on an aircraft?

A

It allows the crew to be alerted when they are being called

18
Q

What best describes the modulation format for a SELCAL encoded call?

A

Consists of two pairs of two audio tones amplitude modulated on the RF

19
Q

What system is used for identifying a specific aircraft for SELCAL?

A

One that uses a four-letter code assigned to the aircraft

20
Q

What is the time between the pairs of tones in a SELCAL transmission?

A

0.2 seconds

21
Q

How is the SELCAL code selected for a specific aircraft?

A

It’s set with rotary switches or jumpers in the aircraft

22
Q

Which of the following is a valid SELCAL code for an aircraft?

A

FLAP

23
Q

The tones used for encoding SELCAL fall within the range of sounds that humans can hear. (1 mark each)

A

yes

24
Q

SELCAL cannot be used with an HF communications system on an aircraft.

true or false

A

false

25
Q

Which of the following best describes the operation of an ELT in an aircraft?

A

It activates automatically in the event of a crash

26
Q

On what frequencies do a 3-frequency ELT transmit?

A

121.500 MHz, 243.0 MHz and 406 MHz

27
Q

What is the primary source of power for an aircraft ELT?

A

The ELT has its own dedicated battery

28
Q

In what format is the information transmitted on the 121.500 MHz and 243.0 MHz frequencies?

A

Analog signal, consisting of a sweeping audio tone

29
Q

When testing an ELT in the aircraft, what frequency is used to monitor the ELT transmission?

A

121.500 MHz

30
Q

What is the proper time of day to test the ELT?

A

Within the first 5 minutes of any UTC hour

31
Q

True or False
COSPAS/SARSAT is the satellite system operated by Russia and the USA.

A

true

32
Q

NOAA is the U.S. government agency that operates the COSPAS/SARSAT system.

A

yes

33
Q

A remote switch is required on a 406 MHz ELT.

true or false

A

true

ELEC 310 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions