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Question #501Radio Theory and Communication Principles

What electrical component is usually composed of a coil of wire?

  1. Switch
  2. Capacitor
  3. Diode
  4. Inductor ✓ Correct answer

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Question #502Basic Electricity and Electronics

What is the voltage across a 10-ohm resistor if a current of 1 ampere flows through it?

  1. 1 volt
  2. 10 volts ✓ Correct answer
  3. 11 volts
  4. 9 volts

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Question #503Basic Electricity and Electronics

Electrical current is measured in which of the following units?

  1. Volts
  2. Watts
  3. Ohms
  4. Amperes ✓ Correct answer

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Question #504Radio Theory and Communication Principles

What is the purpose of the squelch control on a transceiver?

  1. To set the highest level of volume desired
  2. To set the transmitter power level
  3. To adjust the automatic gain control
  4. To mute receiver output noise when no signal is being received ✓ Correct answer

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Question #505Radio Theory and Communication Principles

What is the radio horizon?

  1. The distance at which radio signals between two points are effectively blocked by the curvature of the Earth ✓ Correct answer
  2. The distance from the ground to a horizontally mounted antenna
  3. The farthest point you can see when standing at the base of your antenna tower
  4. The shortest distance between two points on the Earth's surface

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Question #506Radio Theory and Communication Principles

What is a good way to guard against electrical shock at your station?

  1. Use three-wire cords and plugs for all AC powered equipment
  2. Connect all AC powered station equipment to a common safety ground
  3. Use a circuit protected by a ground-fault interrupter
  4. All of these choices are correct ✓ Correct answer

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Question #507Radio Theory and Communication Principles

Why must the metal enclosure of every item of station equipment be grounded?

  1. It prevents blowing of fuses in case of an internal short circuit
  2. It prevents signal overload
  3. It ensures that the neutral wire is grounded
  4. It ensures that hazardous voltages cannot appear on the chassis ✓ Correct answer

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Question #508Radio Equipment, Measurements and Safety

Which of the following is an advantage of an oscilloscope versus a digital voltmeter?

  1. An oscilloscope uses less power
  2. Complex impedances can be easily measured
  3. Input impedance is much lower
  4. Complex waveforms can be measured ✓ Correct answer

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Question #509Basic Electricity and Electronics

What is the peak-to-peak voltage of a sine wave that has an RMS voltage of 120 volts?

  1. 84.8 volts
  2. 169.7 volts
  3. 240.0 volts
  4. 339.4 volts ✓ Correct answer

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Question #510Basic Electricity and Electronics

What is the inductance of a 20 millihenry inductor in series with a 50 millihenry inductor?

  1. .07 millihenrys
  2. 14.3 millihenrys
  3. 70 millihenrys ✓ Correct answer
  4. 1000 millihenrys

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Question #511Basic Electricity and Electronics

What circuit is used to process signals from the RF amplifier and local oscillator and send the result to the IF filter in a super-heterodyne receiver?

  1. Balanced modulator
  2. IF amplifier
  3. Mixer ✓ Correct answer
  4. Detector

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Question #512Radio Theory and Communication Principles

What type of bias is required for an LED to emit light?

  1. Reverse bias
  2. Forward bias ✓ Correct answer
  3. Zero bias
  4. Inductive bias

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Question #513Basic Electricity and Electronics

What is the resistance of a circuit in which a current of 3A through a Resistor connected to 90 volts?

  1. 3 ohms
  2. 30 ohms ✓ Correct answer
  3. 93 ohms
  4. 270 ohms

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Question #514Radio Theory and Communication Principles

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

  1. AM
  2. SSB
  3. PSK
  4. FM ✓ Correct answer

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Question #515Radio Theory and Communication Principles

Q factor of a coil is measure of its

  1. Sensitivity
  2. selectivity ✓ Correct answer
  3. Resistivity
  4. conductivity

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Question #516Radio Theory and Communication Principles

How fast does a radio wave travel through free 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
Explanation: In free space, radio waves travel at the speed of light (approximately 3 × 10^8 m/s).

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Question #517Antennas and Radio Wave Propagation

How does the wavelength related to frequency?

  1. The wavelength gets longer as the frequency increases
  2. The wavelength gets shorter as the frequency increases ✓ Correct answer
  3. There is no relationship between wavelength and frequency
  4. The wavelength depends on the bandwidth of the signal

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Question #518Antennas and Radio Wave Propagation

What is the formula for converting frequency to wavelength

  1. Wavelength in meters equals frequency in hertz multiplied by 300
  2. Wavelength in meters equals frequency in hertz divided by 300
  3. Wavelength in meters equals frequency in megahertz divided by 300
  4. Wavelength in meters equals 300 divided by frequency in megahertz ✓ Correct answer

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Question #519Radio Theory and Communication Principles

What are the frequency limits of VHF spectrum?

  1. 30 to 300 kHz
  2. 30 to 300MHz ✓ Correct answer
  3. 300 to 3000 kHz
  4. 300 to 3000 MHz.

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Question #520Radio Theory and Communication Principles

What are the frequency of UHF spectrum?

  1. 30 to 300 kHz
  2. 30 to 300MHz
  3. 300 to 3000 kHz
  4. 300 to 3000 MHz. ✓ Correct answer

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