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194 matching questions

Question #49Radio Theory and Communication Principles

NICAM technique is used in TV broadcast

  1. For transmitting video
  2. For transmitting mono aural audio
  3. For transmitting stereo audio ✓ Correct answer
  4. For transmitting timing signals
Explanation: NICAM is a digital system used to transmit stereo (and sometimes dual-language) television audio.

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Question #50Radio Theory and Communication Principles

Conventional Facsimile machine sends ______ data over _____ media

  1. Analog, air
  2. Digital, air
  3. Analog, telephone ✓ Correct answer
  4. Digital, telephone
Explanation: Conventional fax machines transmit analogue information over a telephone line.

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Question #71Radio Theory and Communication Principles

The expanded form for TU in Morse code is

  1. Thank u
  2. Thank you ✓ Correct answer
  3. Thank everyone
  4. None of the above
Explanation: TU is the Morse abbreviation for “Thank you”.

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Question #159Radio Theory and Communication Principles

What is the standard unit of frequency?

  1. The megacycle
  2. The Hertz ✓ Correct answer
  3. One thousand cycles per second
  4. The electromagnetic force

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Question #164Radio Theory and Communication Principles

What instrument is used to measure Electromotive Force (EMF) between two points such as the poles of a battery?

  1. Magnetometer
  2. Voltmeter ✓ Correct answer
  3. Ammeter
  4. Ohmmeter

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Question #165Radio Theory and Communication Principles

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

  1. Wave speed
  2. Waveform
  3. Wavelength ✓ Correct answer
  4. Wave spread

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Question #167Radio Theory and Communication Principles

What does 50 hertz (Hz) mean?

  1. 5000 cycles per second
  2. 50 cycles per second ✓ Correct answer
  3. 5000 meters per second
  4. 50 meters per second

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Question #168Radio Theory and Communication Principles

Electromagnetic waves that oscillate more than 20,000 times per second as they travel through space are generally referred to as what?

  1. Gravity waves
  2. Sound waves
  3. Radio waves ✓ Correct answer
  4. Gamma radiation

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Question #169Radio Theory and Communication Principles

How fast does a radio wave travel through space?

  1. At the speed of light ✓ Correct answer
  2. At the speed of sound
  3. Its speed is inversely proportional to its wavelength
  4. Its speed increases as the frequency increases

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Question #172Radio Theory and Communication Principles

What are sound waves in the range between 300 and 3000 Hertz called?

  1. Test signals
  2. Ultrasonic waves
  3. Voice frequencies ✓ Correct answer
  4. Radio frequencies

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Question #173Radio Theory and Communication Principles

What property of a radio wave is often used to identify the different bands amateur radio operators use?

  1. The physical length of the wave ✓ Correct answer
  2. The magnetic intensity of the wave
  3. The time it takes for the wave to travel one mile
  4. The voltage standing wave ratio of the wave

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Question #174Radio Theory and Communication Principles

What is the frequency range of the 2 meter band in the India?

  1. 144 to 146 MHz ✓ Correct answer
  2. 222 to 225 MHz
  3. 434 to 438 MHz
  4. 50 to 54 MHz

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Question #175Radio Theory and Communication Principles

What is used to convert radio signals into sounds we can hear?

  1. Transmitter
  2. Receiver ✓ Correct answer
  3. Microphone
  4. Antenna

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Question #176Radio Theory and Communication Principles

What is used to convert sounds from our voice into radio signals?

  1. Transmitter ✓ Correct answer
  2. Receiver
  3. Speaker
  4. Antenna

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Question #177Radio Theory and Communication Principles

What two devices are combined into one unit in a transceiver?

  1. Receiver, transmitter ✓ Correct answer
  2. Receiver, transformer
  3. Receiver, transistor
  4. Transmitter, deceiver

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Question #180Radio Theory and Communication Principles

Which of the battery types listed below offers the longest life when used with a hand-held radio, assuming each battery is the same physical size?

  1. Lead-acid
  2. Alkaline
  3. Nickel-cadmium
  4. Lithium-ion ✓ Correct answer

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Question #182Radio Theory and Communication Principles

What battery type on this list is not designed to be re-charged?

  1. Nickel-cadmium
  2. Carbon-zinc ✓ Correct answer
  3. Lead-acid
  4. Lithium-ion

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Question #183Radio Theory and Communication Principles

What is required to keep rechargeable batteries in good condition and ready for emergencies?

  1. They must be inspected for physical damage and replaced if necessary
  2. They should be stored in a cool and dry location
  3. They must be given a maintenance recharge at least every 6 months
  4. All of these answers are correct ✓ Correct answer

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Question #184Radio Theory and Communication Principles

What is the best way to get the most amount of energy from a battery?

  1. Draw current from the battery as rapidly as possible
  2. Draw current from the battery at the slowest rate needed ✓ Correct answer
  3. Reverse the leads when the battery reaches the 1/2 charge level
  4. Charge the battery as frequently as possible

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Question #201Radio Theory and Communication Principles

How many milliamperes is the same as 1.5 amperes?

  1. 15 milliamperes
  2. 150 milliamperes
  3. 1500 milliamperes ✓ Correct answer
  4. 15000 mill amperes

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