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Review For Board Exam > SET 1 ECT > Flashcards

SET 1 ECT Flashcards

1
Q

What is the name for the distance a radio wave travels during one complete cycle?

A

Wavelength

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2
Q

How fast does a radio wave travel through free space?

A

At the speed of light

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3
Q

How does the wavelength of a radio wave relate to its frequency?

A

The wavelength gets shorter as the frequency increases

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4
Q

What is the formula for converting frequency to wavelength in meters?

A

Wavelength in meters equals 300 divided by frequency in megahertz

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5
Q

What property of radio waves is often used to identify the different frequency bands?

A

The approximate wavelength

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6
Q

What are the frequency limits of the UHF spectrum?

A

300 to 3000 MHz

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7
Q

What are the frequency limits of the VHF

A

30 to 300 MHz

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8
Q

What are the frequency limits of the VHF

A

30 to 300 MHz

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9
Q

What are the frequency limits of the UHF

A

300 to 3000 MHz

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10
Q

What frequency range is referred to as HF?

A

3 to 30 MHz

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11
Q

What is the approximate velocity of a radio wave as it travels through free space?

A

300,000,000 meters per second

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12
Q

How many milliamperes is 1.5 amperes?

A

1,500 milliamperes

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13
Q

What is another way to specify a radio signal frequency of 1,500,000 hertz?

A

1500 kHz

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14
Q

How many volts are equal to one kilovolt?

A

One thousand volts

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15
Q

How many volts are equal to one microvolt?

A

One one-millionth of a volt

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16
Q

Which of the following is equivalent to 500 milliwatts?

A

0.5 watts

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17
Q

If an ammeter calibrated in amperes is used to measure a 3000- milliampere current, what reading would it show?

A

3 amperes

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18
Q

a frequency readout calibrated in megahertz shows a reading of3.525 MHz, what would it show if it were calibrated in kilohertz?

A

3525 kHz

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19
Q

What happens when the deviation of an FM transmitter is increased?

A

Its signal occupies more bandwidth

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20
Q

How many microfarads are 1,000,000 picofarads?

A

1 microfarad

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21
Q

What is the unit of frequency?

A

Hertz

22
Q

What is the abbreviation that refers to radio frequency signals of all types?

A

RF

23
Q

What determines the amount of deviation of an FM(as opposed to PM) signal?

A

The amplitude of the modulating signal

24
Q

Which of the following is a form of amplitude modulation?

A

Single sideband

25
Q

What type of modulation is most commonly used for VHF packet radio transmissions?

A

SSB

26
Q

Which type of voice modulation is most often used for long- distance or weak signal contacts on the VHF and UHF bands?

A

SSB

27
Q

Which type of modulation is most commonly used for VHF and UHF voice repeaters?

A

FM

28
Q

Which of the following types of emission has the narrowest bandwidth?

A

CW()

29
Q

Which sideband is normally used for 10 meter HF, VHF and UHF single-sideband communications?

A

Upper sideband

30
Q

What is the primary advantage of single sideband over FM for voice transmissions?

A

SSB signals have narrower bandwidth ()

31
Q

What is the approximate bandwidth of a single sideband voice signal?

A

3kHz

32
Q

What is the approximate bandwidth of a VHF repeater FMphone signal?

A

Between 5 and 15 kHz

33
Q

What is the typical bandwidth of analog fast-scan TV transmissions on the 70 cm band?

A

About 6 MHz

34
Q

What is the approximate maximum bandwidth required to transmit a CW signal?

A

150Hz

35
Q

What type of amateur station simultaneously retransmits the signal of another amateur station on a different channel or channels?

A

Repeater station

36
Q

What could be used in place of a regular speaker to help you copy signals in a noisy area?

A

A set of headphones

37
Q

What term describes the number of times per second that an alternating current reverses direction?

A

Frequency

38
Q

Electrical current is measured in which of the following units?

A

Amperes

39
Q

Electrical power is measured in which of the following units?

A

watts

40
Q

Which term describes the rate at which electrical energy is used?

A

Power

41
Q

What is the name for the flow of electrons in an electric circuit?

A

Current

42
Q

What is the basic unit of electromotive force?

A

The volt

43
Q

What is the name for a current that flows only in one direction?

A

Direct current

44
Q

What is the formula used to calculate electrical power in a DC circuit?

A

Power (P) equals voltage (E) multiplied by current (I)

45
Q

What is the electrical term for the electromotive force (EMF) that causes electron flow?

A

Voltage

46
Q

How much power is being used in a circuit when the applied voltage is 12 volts DC and the current is 2.5 amperes?

A

30 watts

47
Q

Which of the following is a good electrical conductor?

A

Copper

48
Q

Which of the following is a good electrical insulator?

A

Glass

49
Q

What is the name for a current that reverses direction on a regular basis?

A

Alternating current

50
Q

How many amperes are flowing in a circuit when the applied voltage is 12 volts DC and the load is 120 watts?

A

10 amperes

51
Q

What formula is used to calculate current in a circuit?

A

Current (I) equals voltage (E) divided by resistance (R)

Review For Board Exam (17 decks)

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