Element 8 Practice Test

Tap an answer to see the keyed choice and the radar principle behind it, with the pool number.

What RADAR component controls timing throughout the system?

Pick an answer, then press Check answer. Then you see Correct or Not quite, with the reason. Keys: A to D pick, Enter checks.

Print covers the next 50 questions. Share this set copies a link to the same questions in the same order.

Exam mode: 50 questions, no time limit, 38 right to pass (76%).

More options

Unofficial practice questions, not affiliated with the Federal Communications Commission (FCC). Bank checked October 2, 2026.

Next step Element 3 radiotelephone practiceElement 1 marine radio practice

All 279 questions

A: RADAR Principles 49

  • A basic sample-and-hold circuit contains: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-7A2, key topic 7: Components-1
  • A Gunn diode oscillator takes advantage of what effect? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A5, key topic 8: Components-2
  • A pulse RADAR has a pulse repetition frequency (PRF) of 400 Hz, a pulse width of 1 microsecond, and a peak power of 100 kilowatts. The average power of the RADAR transmitter is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A1, key topic 4: Power, Pulse Width, PRR
  • A pulse RADAR transmits a 0.5 microsecond RF pulse with a peak power of 100 kilowatts every 1600 microseconds. This RADAR has: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A3, key topic 4: Power, Pulse Width, PRR
  • A RADAR operating at a frequency of 3 GHz has a wavelength of approximately: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A4, key topic 3: Frequency and Wavelength
Show all 279 questions (274 more)

A: RADAR Principles, continued

  • A radio wave will travel a distance of three nautical miles in: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A1, key topic 2: Distance and Time
  • A search RADAR has a pulse width of 1.0 microsecond, a pulse repetition frequency (PRF) of 900 Hz, and an average power of 18 watts. The unit’s peak power is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A6, key topic 4: Power, Pulse Width, PRR
  • A shipboard RADAR transmitter has a pulse repetition frequency (PRF) of 1,000 Hz, a pulse width of 0.5 microseconds, peak power of 150 KW, and a minimum range of 75 meters. Its duty cycle is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A2, key topic 4: Power, Pulse Width, PRR
  • An S-band RADAR operates in which frequency band? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A3, key topic 3: Frequency and Wavelength
  • An X band RADAR operates in which frequency band? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A6, key topic 3: Frequency and Wavelength
  • The basic frequency determining element in a Gunn oscillator is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A1, key topic 8: Components-2
  • Blocking oscillators operate on the formula of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-9A1, key topic 9: Circuits-1
  • Choose the most correct statement containing the parameters which control the size of the target echo. FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A1, key topic 1: Marine RADAR Systems
  • Choose the most correct statement: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-9A6, key topic 9: Circuits-1
  • Fine adjustments of a reflex klystron are accomplished by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A6, key topic 8: Components-2
  • For a range of 5 nautical miles, the RADAR pulse repetition frequency should be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A1, key topic 5: Range, Pulse Width, PRF
  • For a range of 10 nautical miles, the RADAR pulse repetition frequency (PRF) should be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A6, key topic 5: Range, Pulse Width, PRF
  • For a range of 30 nautical miles, the RADAR pulse repetition frequency should be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A5, key topic 5: Range, Pulse Width, PRF
  • For a range of 100 nautical miles, the RADAR pulse repetition frequency should be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A2, key topic 5: Range, Pulse Width, PRF
  • Frequencies generally used for marine RADAR are in the ___ part of the radio spectrum. FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A1, key topic 3: Frequency and Wavelength
  • How long would it take for a RADAR pulse to travel to a target 10 nautical miles away and return to the RADAR receiver? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A5, key topic 2: Distance and Time
  • If a RADAR transmitter has a pulse repetition frequency (PRF) of 900 Hz, a pulse width of 0.5 microseconds and a peak power of 15 kilowatts, what is its average power output? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A4, key topic 4: Power, Pulse Width, PRR
  • If a target is 5 miles away, how long does it take for the RADAR echo to be received back at the antenna? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A4, key topic 2: Distance and Time
  • If the PRF is 2500 Hz, what is the PRI? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A1, key topic 6: Pulse Width - Pulse Repetition Rates
  • If the pulse repetition frequency (PRF) is 2000 Hz, what is the pulse repetition interval (PRI)? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A2, key topic 6: Pulse Width - Pulse Repetition Rates
  • If the RADAR unit has a pulse repetition frequency (PRF) of 2000 Hz and a pulse width of 0.05 microseconds, what is the duty cycle? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A4, key topic 6: Pulse Width - Pulse Repetition Rates
  • The major advantage of an S-band RADAR over an X-band RADAR is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A5, key topic 3: Frequency and Wavelength
  • The minimum range of a RADAR is determined by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A3, key topic 5: Range, Pulse Width, PRF
  • One RADAR mile is how many microseconds? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A2, key topic 2: Distance and Time
  • The phantastron circuit is capable of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-9A3, key topic 9: Circuits-1
  • Practical RADAR operation requires the use of microwave frequencies so that: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-3A2, key topic 3: Frequency and Wavelength
  • The primary operating frequency of a reflex klystron is controlled by the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A4, key topic 8: Components-2
  • The pulse repetition rate (PRR) refers to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A3, key topic 6: Pulse Width - Pulse Repetition Rates
  • RADAR range is measured by the constant: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A3, key topic 2: Distance and Time
  • Short range RADARs would most likely transmit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-5A4, key topic 5: Range, Pulse Width, PRF
  • Silicon crystals: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-7A4, key topic 7: Components-1
  • Small targets are best detected by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A5, key topic 6: Pulse Width - Pulse Repetition Rates
  • The sweep frequency of a RADAR indicator is determined by what parameter? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A6, key topic 1: Marine RADAR Systems
  • What is the average power if the RADAR set has a PRF of 1000 Hz, a pulse width of 1 microsecond, and a peak power rating of 100 kilowatts? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-4A5, key topic 4: Power, Pulse Width, PRR
  • What is the distance in nautical miles to a target if it takes 308.5 microseconds for the RADAR pulse to travel from the RADAR antenna to the target and back. FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-2A6, key topic 2: Distance and Time
  • What is the relationship between pulse repetition rate and pulse width? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-6A6, key topic 6: Pulse Width - Pulse Repetition Rates
  • What RADAR component controls timing throughout the system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A4, key topic 1: Marine RADAR Systems
  • What type of transmitter power is measured over a period of time? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A3, key topic 1: Marine RADAR Systems
  • When comparing a TTL and a CMOS NAND gate: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-7A3, key topic 7: Components-1
  • When comparing TTL and CMOS logic families, which of the following is true: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A3, key topic 8: Components-2
  • Which is typical current for a silicon crystal used in a RADAR mixer or detector circuit? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-7A5, key topic 7: Components-1
  • Which of the following components allows the use of a single antenna for both transmitting and receiving? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A5, key topic 1: Marine RADAR Systems
  • Which of the following has NO effect on the maximum range capability? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-1A2, key topic 1: Marine RADAR Systems
  • Which of the following is not a method of analog-to-digital conversion? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-8A2, key topic 8: Components-2

B: Transmitting Systems 48

  • A circulator provides what function in the RF section of a RADAR system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B4, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • A DC keep-alive potential: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B6, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • A directional coupler has an attenuation of -30 db. A measurement of 100 milliwatts at the coupler indicates the power of the line is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B5, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • A ferrite circulator is most commonly used in what portion of a RADAR system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B3, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • A keep-alive voltage is applied to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B5, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • A major consideration for the use of a switching regulator power supply over a linear regulator is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B5, key topic 18: Power Supplies
  • A negative voltage is commonly applied to the magnetron cathode rather than a positive voltage to the magnetron anode because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B5, key topic 12: Magnetrons
  • A pulse-width modulator in a switching power supply is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B3, key topic 18: Power Supplies
  • A shipboard RADAR uses a PFN driving a magnetron cathode through a step-up transformer. This results in which type of modulation? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B3, key topic 13: Modulation
  • An advantage of resonant charging is that it: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B1, key topic 18: Power Supplies
  • An artificial transmission line is used for: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B6, key topic 14: Pulse Forming Networks Modulation
  • The anode of a magnetron is normally maintained at ground potential: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B6, key topic 12: Magnetrons
  • The ATR box: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B1, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • The characteristic of the magnetron output pulse that relates to accurate range measurement is its: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B2, key topic 12: Magnetrons
  • The characteristics of a field-effect transistor (FET) used in a modern RADAR switching power supply can be compared as follows: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B2, key topic 18: Power Supplies
  • The ferrite material in a circulator is used as a(an): FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B1, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • High voltage is applied to what element of the magnetron? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B1, key topic 12: Magnetrons
  • In a circular resonant cavity with flat ends, the E-field and the H-field form with specific relationships. The: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B2, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • In a fixed-frequency switching power supply, the pulse width of the switching circuit will increase when: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B4, key topic 18: Power Supplies
  • In a pulse modulated magnetron what device determines the shape and width of the pulse? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B4, key topic 13: Modulation
  • In a solid-state RADAR modulator, the duration of the transmitted pulse is determined by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B1, key topic 13: Modulation
  • The magnetron is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B1, key topic 11: Transmitting Systems
  • The magnetron is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B4, key topic 12: Magnetrons
  • The modulation frequency of most RADAR systems is between: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B2, key topic 13: Modulation
  • Operation of any RADAR system begins in the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B3, key topic 17: Timer - Trigger - Synchronizer Circuits
  • The pulse developed by the modulator may have an amplitude greater than the supply voltage. This is possible by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B1, key topic 14: Pulse Forming Networks Modulation
  • Pulse RADARs require precise timing for their operation. Which type circuit below might best be used to provide these accurate timing pulses? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B5, key topic 17: Timer - Trigger - Synchronizer Circuits
  • Pulse transformers and pulse-forming networks are commonly used to shape the microwave energy burst RADAR transmitter. The switching devices most often used in such pulse-forming circuits are: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B2, key topic 14: Pulse Forming Networks Modulation
  • Pulse-forming networks are usually composed of the following: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B5, key topic 14: Pulse Forming Networks Modulation
  • The purpose of a modulator in the transmitter section of a RADAR is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B6, key topic 13: Modulation
  • The purpose of the modulator is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B2, key topic 11: Transmitting Systems
  • The purpose of the Pulse Forming Network is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B4, key topic 11: Transmitting Systems
  • The purpose of the pulse-forming network is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B3, key topic 14: Pulse Forming Networks Modulation
  • The purpose of the Synchronizer is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B5, key topic 11: Transmitting Systems
  • The shape and duration of the high-voltage pulse delivered to the magnetron is established by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-14B4, key topic 14: Pulse Forming Networks Modulation
  • The timer circuit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B4, key topic 17: Timer - Trigger - Synchronizer Circuits
  • The TR box: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B3, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • The triggering section is also known as the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B2, key topic 17: Timer - Trigger - Synchronizer Circuits
  • Unblanking pulses are produced by the timer circuit. Where are they sent? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B6, key topic 17: Timer - Trigger - Synchronizer Circuits
  • What device is located between the magnetron and the mixer and prevents received signals from entering the magnetron? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B4, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • What device is used as a transmitter in a marine RADAR system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-12B3, key topic 12: Magnetrons
  • What device(s) may act as the modulator of a RADAR system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-13B5, key topic 13: Modulation
  • What is the purpose or function of the RADAR duplexer/circulator? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-15B6, key topic 15: TR - ATR - Circulators - Directional Couplers-1
  • What RADAR circuit determines the pulse repetition rate (PRR)? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-17B1, key topic 17: Timer - Trigger - Synchronizer Circuits
  • When a pulse RADAR is radiating, which elements in the TR box are energized? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-16B2, key topic 16: TR - ATR - Circulators - Directional Couplers-2
  • Which of the following characteristics are true of a power MOSFET used in a RADAR switching supply? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-18B6, key topic 18: Power Supplies
  • Which of the following is not part of the transmitting system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B6, key topic 11: Transmitting Systems
  • Which of the following statements about most modern RADAR transmitter power supplies is false? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-11B3, key topic 11: Transmitting Systems

C: Receiving Systems 53

  • A circuit used to develop AFC voltage in a RADAR receiver is called the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-24C2, key topic 24: Automatic Frequency Control - AFC
  • A constant frequency switching power supply regulator with an input voltage of 165 volts DC, and a switching frequency of 20 kHz, has an “ON” time of 27 microseconds when supplying 1 ampere to its load. What is the output voltage across the load? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-26C2, key topic 26: Power Supplies
  • A logarithmic IF amplifier is preferable to a linear IF amplifier in a RADAR receiver because it: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C4, key topic 22: Amplifiers
  • A RADAR transmitter is operating on 3.0 GHz and the reflex klystron local oscillator, operating at 3.060 GHz, develops a 60 MHz IF. If the magnetron drifts higher in frequency, the AFC system must cause the klystron repeller plate to become: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-24C5, key topic 24: Automatic Frequency Control - AFC
  • The AFC system is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-24C1, key topic 24: Automatic Frequency Control - AFC
  • An AFC system keeps the receiver tuned to the transmitted signal by varying the frequency of the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-24C4, key topic 24: Automatic Frequency Control - AFC
  • An ion discharge (TR) cell is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C5, key topic 28: Miscellaneous
  • An RF mixer has what purpose in a RADAR system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-20C3, key topic 20: Mixers
  • The condition known as “glint” refers to a shifting of clutter with each RADAR pulse and can be caused by a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C4, key topic 28: Miscellaneous
  • The error voltage from the discriminator is applied to the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-21C1, key topic 21: Local Oscillators
  • The high-gain IF amplifiers in a RADAR receiver may amplify a 2 microvolt input signal to an output level of 2 volts. This amount of amplification represents a gain of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C5, key topic 22: Amplifiers
  • How may the frequency of the klystron be varied? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-21C6, key topic 21: Local Oscillators
  • The I.F. Amplifier bandwidth is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C3, key topic 22: Amplifiers
  • In a RADAR receiver AGC and IAGC can vary between: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C6, key topic 22: Amplifiers
  • In a RADAR receiver the most common types of interference are? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C5, key topic 27: Interference Issues
  • In a RADAR receiver, the RF power amplifier: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C6, key topic 19: Receiving Systems
  • In a RADAR unit, the local oscillator is a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-21C2, key topic 21: Local Oscillators
  • In a RADAR unit, the mixer uses a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-20C4, key topic 20: Mixers
  • In a RADAR unit, the mixer uses: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-20C6, key topic 20: Mixers
  • In the AFC system, the discriminator compares the frequencies of the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-24C3, key topic 24: Automatic Frequency Control - AFC
  • In the receive mode, frequency conversion is generally accomplished by a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-20C2, key topic 20: Mixers
  • In video amplifiers, compensation for the input and output stage capacitances must be accomplished to prevent distorting the video pulses. This compensation is normally accomplished by connecting: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C3, key topic 23: Detectors - Video Amplifiers
  • The klystron local oscillator is constantly kept on frequency by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-21C5, key topic 21: Local Oscillators
  • Logarithmic receivers: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C2, key topic 19: Receiving Systems
  • The MTI circuit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C2, key topic 28: Miscellaneous
  • Noise can appear on the LCD as: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C3, key topic 27: Interference Issues
  • Noise can: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C6, key topic 27: Interference Issues
  • One of the best methods of reducing noise in a RADAR receiver is? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C1, key topic 27: Interference Issues
  • Overcoupling in a RADAR receiver will cause? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C1, key topic 22: Amplifiers
  • The primary cause of noise in a RADAR receiver can be attributed to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C2, key topic 27: Interference Issues
  • Prior to making “power-on” measurements on a switching power supply, you should be familiar with the supply because of the following: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-26C1, key topic 26: Power Supplies
  • The purpose of the discriminator circuit in a RADAR set is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C1, key topic 28: Miscellaneous
  • RADAR interference on a communications receiver appears as: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-27C4, key topic 27: Interference Issues
  • RADAR receivers are similar to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C3, key topic 19: Receiving Systems
  • Sea clutter on the RADAR scope cannot be effectively reduced using front panel controls. What circuit would you suspect is faulty? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C4, key topic 25: Sea Clutter - STC
  • Sea return is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C3, key topic 25: Sea Clutter - STC
  • The sensitivity time control (STC) circuit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C6, key topic 25: Sea Clutter - STC
  • The STC circuit is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C1, key topic 25: Sea Clutter - STC
  • The STC circuit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C2, key topic 25: Sea Clutter - STC
  • The usual intermediate frequency of a shipboard RADAR unit is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-22C2, key topic 22: Amplifiers
  • The video (second) detector in a pulse modulated RADAR system would most likely use a/an: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C6, key topic 23: Detectors - Video Amplifiers
  • Video amplifiers in pulse RADAR receivers must have a broad bandwidth because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C2, key topic 23: Detectors - Video Amplifiers
  • What circuit controls the suppression of sea clutter? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-25C5, key topic 25: Sea Clutter - STC
  • What device(s) could be used as the local oscillator in a RADAR receiver? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-21C4, key topic 21: Local Oscillators
  • What is the main difference between an analog and a digital receiver? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C5, key topic 19: Receiving Systems
  • What section of the receiving system sends signals to the display system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C4, key topic 19: Receiving Systems
  • When monitoring the gate voltage of a power MOSFET in the switching power supply of a modern RADAR, you would expect to see the gate voltage change from “low” to “high” by how much? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-26C5, key topic 26: Power Supplies
  • When the receiver employs an MTI circuit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C6, key topic 28: Miscellaneous
  • Where is a RF attenuator used in a RADAR unit? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-28C3, key topic 28: Miscellaneous
  • Which of the following signals are usually an input to the video amplifier? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C5, key topic 23: Detectors - Video Amplifiers
  • Which of the following signals is not usually an input to the video amplifier? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C4, key topic 23: Detectors - Video Amplifiers
  • Which of the following statements is correct? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-23C1, key topic 23: Detectors - Video Amplifiers
  • Which of the following statements is true? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-19C1, key topic 19: Receiving Systems

D: Display & Control Systems 59

  • A gated LC oscillator, operating at 27 kHz, is being used to develop range markers. If each cycle is converted to a range mark, the range between markers will be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D3, key topic 32: Fixed Range Markers
  • A true bearing presentation appears as follows: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D6, key topic 34: EBL, Azimuth and True Bearing
  • Accurate range markers must be developed using very narrow pulses. A circuit that could be used to provide these high-quality pulses for the CRT is a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D1, key topic 32: Fixed Range Markers
  • An important component of the VRM system is the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D5, key topic 33: Variable Range Markers
  • The ARPA term CPA refers to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D6, key topic 36: ARPA - CAS
  • Bearing information from the gyro is used to provide the following: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D4, key topic 34: EBL, Azimuth and True Bearing
  • Bearing resolution is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D4, key topic 38: Miscellaneous
  • The circuit that develops timing signals is called the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D2, key topic 31: Timing Circuits
  • The display power supply provides the following: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-37D1, key topic 37: Display System Power Supplies
  • The Electronic Bearing Line is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D2, key topic 34: EBL, Azimuth and True Bearing
  • The heading flash is a momentary intensification of the sweep line on the PPI presentation. Its function is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D1, key topic 38: Miscellaneous
  • How do you eliminate stationary objects such as trees, buildings, bridges, etc., from the PPI presentation? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D6, key topic 38: Miscellaneous
  • How does the dual memory function reduce sea clutter? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D4, key topic 35: Memory Systems
  • How is the variable range marker usually adjusted for accuracy? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D3, key topic 33: Variable Range Markers
  • How many deflection coils are driven by the sweep amplifier? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D4, key topic 30: Video Amplifiers and Sweep Circuits
  • How many sequential memory cells with target returns are required to display the target? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D5, key topic 35: Memory Systems
  • In a digitized RADAR, the 360 degree sweep is divided into how many digitized segments? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D1, key topic 35: Memory Systems
  • In a display system power supply what is the purpose of the chopper? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-37D3, key topic 37: Display System Power Supplies
  • In a display system power supply, what is the purpose of the inverter? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-37D4, key topic 37: Display System Power Supplies
  • In a raster-type display, the electron beam is scanned: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D5, key topic 29: Displays
  • In order to ensure that a practical filter is able to remove undesired components from the output of an analog-to-digital converter, the sampling frequency should be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D3, key topic 38: Miscellaneous
  • LCD patterns are formed when: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D4, key topic 29: Displays
  • The main purpose of the sweep generator is to provide: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D5, key topic 30: Video Amplifiers and Sweep Circuits
  • The main purpose of the video amplifier is to provide: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D6, key topic 30: Video Amplifiers and Sweep Circuits
  • The major advantage of digitally processing a RADAR signal is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D2, key topic 38: Miscellaneous
  • Modern liquid crystal displays have a pixel count of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D1, key topic 29: Displays
  • The output from the synchronizer usually consists of a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D5, key topic 31: Timing Circuits
  • The output of an RC integrator, when driven by a square wave with a period of much less than one time constant is a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-38D5, key topic 38: Miscellaneous
  • The panel control for the variable range marker is normally a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D4, key topic 33: Variable Range Markers
  • The purpose of the aquadag coating on the CRT is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D3, key topic 29: Displays
  • The purpose of the Electronic Bearing Line is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D1, key topic 34: EBL, Azimuth and True Bearing
  • The purpose of the sweep amplifier is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D3, key topic 30: Video Amplifiers and Sweep Circuits
  • The purpose of the variable range marker is to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D2, key topic 33: Variable Range Markers
  • Range markers are determined by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D2, key topic 32: Fixed Range Markers
  • Select the statement, which is most correct regarding a raster scan display. FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D6, key topic 29: Displays
  • The ship’s speed indication on the ARPA display can be set manually, but does not change with changes in the vessel’s speed. What other indication would point to a related equipment failure? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D1, key topic 36: ARPA - CAS
  • The sweep drive is initiated by what circuit? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D6, key topic 31: Timing Circuits
  • The synchronizer primarily affects the following circuit or function: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D4, key topic 31: Timing Circuits
  • The term DRAM stands for: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D3, key topic 35: Memory Systems
  • Timing circuits are used to provide what function? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D1, key topic 31: Timing Circuits
  • The variable range marker signal is normally fed to the input of the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D1, key topic 33: Variable Range Markers
  • Voltages used in CRT anode circuits are in what range of value? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-29D2, key topic 29: Displays
  • What are the usual input signals to the video amplifier? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D1, key topic 30: Video Amplifiers and Sweep Circuits
  • What display system power supply output would use a tripler circuit? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-37D6, key topic 37: Display System Power Supplies
  • What does the term ARPA/CAS refer to? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D2, key topic 36: ARPA - CAS
  • What is the distance between range markers if the controlling oscillator is operating at 20 kHz? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D5, key topic 32: Fixed Range Markers
  • What is the primary purpose of display system memory? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D6, key topic 35: Memory Systems
  • What is the purpose or function of the “Trial Mode” used in most ARPA equipment? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D5, key topic 36: ARPA - CAS
  • What would be a common switching frequency for a display system power supply? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-37D5, key topic 37: Display System Power Supplies
  • What would be the frequency of a range ring marker oscillator generating range rings at 10 nautical miles intervals? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D4, key topic 32: Fixed Range Markers
  • What would be the frequency of a range ring marker oscillator generating range rings at intervals of 0.25 nautical miles? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-32D6, key topic 32: Fixed Range Markers
  • Which answer best describes a line on the display which indicates a target’s position. The speed is shown by the length of the line and the course by the direction of the line. FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D4, key topic 36: ARPA - CAS
  • Which of the following functions is not affected by the timing circuit? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-31D3, key topic 31: Timing Circuits
  • Which of the following inputs is required to indicate azimuth? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D3, key topic 34: EBL, Azimuth and True Bearing
  • Which of the following statements about the Variable Range Marker system is correct? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-33D6, key topic 33: Variable Range Markers
  • Which of the following statements about “true bearing” is correct? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-34D5, key topic 34: EBL, Azimuth and True Bearing
  • Which of the following would not be considered an input to the computer of a collision avoidance system? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-36D3, key topic 36: ARPA - CAS
  • Which of the following would not normally be an input to the video amplifier? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-30D2, key topic 30: Video Amplifiers and Sweep Circuits
  • While troubleshooting a memory problem in a raster scan RADAR, you discover that the “REFRESH” cycle is not operating correctly. What type of memory circuit are you working on? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-35D2, key topic 35: Memory Systems

E: Antenna Systems 30

  • A certain length of transmission line has a characteristic impedance of 72 ohms. If the line is cut at its center, each half of the transmission line will have a ZO of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E4, key topic 40: Transmission Lines
  • A microwave transmission line constructed of a center conductor suspended between parallel conductive ground planes is called: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E2, key topic 42: Waveguides-1
  • A right-angle bend in an X-band waveguide must have a radius greater than: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E3, key topic 43: Waveguides-2
  • A rotary joint is used to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E1, key topic 43: Waveguides-2
  • A typical shipboard RADAR antenna is a: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E2, key topic 39: Antenna Systems
  • A waveguide is used at RADAR microwave frequencies because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E4, key topic 42: Waveguides-1
  • An antenna synchro transmitter is composed of the following: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E5, key topic 41: Antenna to Display Interface
  • At microwave frequencies, waveguides are used instead of conventional coaxial transmission lines because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E6, key topic 43: Waveguides-2
  • The center of the transmitted lobe from a slotted waveguide array is: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E4, key topic 39: Antenna Systems
  • The following is true concerning waveguides: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E5, key topic 43: Waveguides-2
  • Good bearing resolution largely depends upon: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E3, key topic 39: Antenna Systems
  • How does antenna length affect the horizontal beamwidth of the transmitted signal? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E5, key topic 39: Antenna Systems
  • How is the signal removed from a waveguide or magnetron? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E6, key topic 42: Waveguides-1
  • If long-length transmission lines are not properly shielded and terminated: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E3, key topic 40: Transmission Lines
  • The impedance total (ZO) of a transmission line can be calculated by ZO = √L/C when L and C are known. When a section of transmission line contains 250 microhenries of L and 1000 picofarads of C, its impedance total (ZO) will be: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E2, key topic 40: Transmission Lines
  • On a basic synchro system, the angular information is carried on the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E2, key topic 41: Antenna to Display Interface
  • The position of the PPI scope sweep must indicate the position of the antenna. The sweep and antenna positions are frequently kept in synchronization by the use of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E1, key topic 41: Antenna to Display Interface
  • RADAR antenna direction must be sent to the display in all ARPAs or RADAR systems. How is this accomplished? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E6, key topic 41: Antenna to Display Interface
  • Resistive losses in a waveguide are very small because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E2, key topic 43: Waveguides-2
  • Slotted waveguide arrays, when fed from one end exhibit: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E1, key topic 39: Antenna Systems
  • Standing waves on a transmission line may be an indication that: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E5, key topic 40: Transmission Lines
  • To insert RF energy into or extract RF energy from a waveguide, which of the following would not be used? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-43E4, key topic 43: Waveguides-2
  • The VSWR of a microwave transmission line device might be measured using: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E1, key topic 40: Transmission Lines
  • Waveguide theory is based on the principals of: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E5, key topic 42: Waveguides-1
  • Waveguide theory is based upon: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E3, key topic 42: Waveguides-1
  • Waveguides can be constructed from: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-42E1, key topic 42: Waveguides-1
  • What is the most common type of antenna position indicating device used in modern RADARs? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E3, key topic 41: Antenna to Display Interface
  • What is the most common type of RADAR antenna used aboard commercial maritime vessels? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-39E6, key topic 39: Antenna Systems
  • What precautions should be taken with horizontal waveguide runs? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-40E6, key topic 40: Transmission Lines
  • Which of the following statements about antenna resolvers is correct? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-41E4, key topic 41: Antenna to Display Interface

F: Installation, Maintenance & Repair 40

  • A defective crystal in the AFC section will cause: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-45F2, key topic 45: Equipment Faults-2
  • A high magnetron current indicates a/an: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F5, key topic 46: Equipment Faults-3
  • A non-magnetic screwdriver should always be used when replacing what component? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F5, key topic 48: Maintenance
  • A thick layer of rust and corrosion on the surface of the parabolic dish will have what effect? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F1, key topic 48: Maintenance
  • An increase in magnetron current that coincides with a decrease in power output is an indication of what? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F3, key topic 46: Equipment Faults-3
  • An increase in the deflection on the magnetron current meter could likely be caused by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F6, key topic 47: Equipment Faults-4
  • Before testing a RADAR transmitter, it would be a good idea to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F2, key topic 50: Safety
  • Choose the most correct statement with respect to component damage from electrostatic discharge: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F1, key topic 50: Safety
  • The echo box is used for: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F2, key topic 48: Maintenance
  • If a CRT is dropped: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F5, key topic 50: Safety
  • If the magnetron is allowed to operate without the magnetic field in place: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F1, key topic 47: Equipment Faults-4
  • If the TR tube malfunctions: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-45F5, key topic 45: Equipment Faults-2
  • In a marine RADAR set, a high VSWR is indicated at the magnetron output. The waveguide and rotary joint appear to be functioning properly. What component may be malfunctioning? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F4, key topic 47: Equipment Faults-4
  • In a RADAR system, waveguides should be installed: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F5, key topic 49: Installation
  • In a RADAR unit, if the crystal mixer becomes defective, replace the: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F2, key topic 46: Equipment Faults-3
  • In a RADAR using digital video processing, a bright, wide ring appears at a fixed distance from the center of the display on all digital ranges. The transmitter is operating normally. What receiver circuit would you suspect is causing the problem? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F5, key topic 44: Equipment Faults-1
  • The indicated distance from your own vessel to a lighthouse is found to be in error. What circuit would you suspect? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-45F6, key topic 45: Equipment Faults-2
  • It is reported that the RADAR is not receiving small targets. The most likely causes are: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F4, key topic 46: Equipment Faults-3
  • Long horizontal sections of waveguides are not desirable because: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F4, key topic 49: Installation
  • Loss of distant targets during and immediately after wet weather indicates: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F3, key topic 47: Equipment Faults-4
  • Low or no mixer current could be caused by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F6, key topic 46: Equipment Faults-3
  • On a vessel with two RADARs, one has a different range indication on a specific target than the other. How would you determine which RADAR is incorrect? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F5, key topic 47: Equipment Faults-4
  • Prior to removing, servicing or making measurements on any solid state circuit boards from the RADAR set, the operator should ensure that: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F6, key topic 50: Safety
  • The RADAR display has sectors of solid video (spoking). What would be the first thing to check? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-45F3, key topic 45: Equipment Faults-2
  • RADAR interference to a communications receiver is eliminated by: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F2, key topic 49: Installation
  • Range rings on the PPI indicator are oval in shape. Which circuit would you suspect is faulty? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F2, key topic 44: Equipment Faults-1
  • The raster scan RADAR display has missing video in a rectangular block on the screen. Where is the most likely problem area? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F6, key topic 44: Equipment Faults-1
  • Silicon crystals are used in RADAR mixer and detector stages. Using an ohmmeter, how might a crystal be checked to determine if it is functional? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-46F1, key topic 46: Equipment Faults-3
  • Targets displayed on the RADAR display are not on the same bearing as their visual bearing. What should you first suspect? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-47F2, key topic 47: Equipment Faults-4
  • What is the most important factor to consider in locating the antenna? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F6, key topic 49: Installation
  • What kind of display would indicate water in the waveguide? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F6, key topic 48: Maintenance
  • What should be done to the interior surface of a waveguide in order to minimize signal loss? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F3, key topic 48: Maintenance
  • What would be the most likely defective area when there is no target video in the center of the CRT and the blank spot gets smaller in diameter as your range scale is increased? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F3, key topic 44: Equipment Faults-1
  • When you examine the RADAR you notice that there is no target video in the center of the CRT. The blank spot gets smaller in diameter as you increase the range scale. What operator front panel control could be misadjusted? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F1, key topic 44: Equipment Faults-1
  • Which of the following is the most useful instrument for RADAR servicing? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-48F4, key topic 48: Maintenance
  • While making repairs or adjustments to RADAR units: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F3, key topic 50: Safety
  • While removing a CRT from its operating casing, it is a good idea to: FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-50F4, key topic 50: Safety
  • While the vessel is docked the presentation of the pier is distorted near the center of the PPI with the pier appearing to bend in a concave fashion. This is a primary indication of what? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-44F4, key topic 44: Equipment Faults-1
  • Why is coaxial cable often used for S-band installations instead of a waveguide? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F1, key topic 49: Installation
  • Why should long horizontal runs of waveguide be avoided? FCC Commercial Element 8 question pool (approved June 25, 2009), question 8-49F3, key topic 49: Installation

How this list was compiled: Questions, answer choices and keyed answers are from the FCC Commercial Element 8 Question Pool (approved 25 June 2009; 300 questions, 6 subelements, 50 key topics), the file the FCC links from its commercial operator examinations page as Element 8: https://www.fcc.gov/sites/default/files/Element%208%20Question%20Pool%20updated%2003062024.pdf . fcc.gov could not be opened on 2026-10-02, so the file was read from the Internet Archive capture of that address dated 2026-03-20 (https://web.archive.org/web/20260320154346/https://www.fcc.gov/sites/default/files/Element%208%20Question%20Pool%20updated%2003062024.pdf); the file is named "updated 03062024" and was last changed on March 6, 2024. The examinations page (https://www.fcc.gov/wireless/bureau-divisions/mobility-division/commercial-radio-operator-license-program/examinations, page dated by the FCC March 6, 2024) was read from the capture dated 2026-02-10 (https://web.archive.org/web/20260210033816/https://www.fcc.gov/wireless/bureau-divisions/mobility-division/commercial-radio-operator-license-program/examinations): it lists this file as the Element 8 pool and gives the exam as at least 38 out of 50 questions. License and element requirements were read in 47 CFR 13.201, 13.203, 13.207 and 13.215 at https://www.law.cornell.edu/cfr/text/47/13.201 and the pages beside it on 2026-10-02. Checked 2026-10-02. Licence: The questions, choices and keyed answers are the published FCC question pool, which the FCC releases to the public so that candidates can study it (47 CFR 13.215). The pool file carries no copyright or reuse statement. The explanations are own work, written for this site. Nothing is taken from a prep company, a study guide or another practice test.

How it works

This unofficial Element 8 practice test holds 279 of the 300 questions in the pool the Federal Communications Commission publishes for the Ship Radar Endorsement. Start from, under the question, picks a subelement, and the 50-question Exam mode needs 38 right.

Read the full guide

What the endorsement takes

47 CFR 13.201(b)(7) lists the Ship Radar Endorsement as Written Element 8 alone. Section 13.203 describes the element as the theory and practice of installing, servicing and maintaining ship radar used for marine navigation.

How the pool is laid out

Fifty key topics of six questions sit in six subelements. Each heading gives its share of the exam: Radar Principles 10 questions, Transmitting Systems 8, Receiving Systems 10, Display and Control Systems 10, Antenna Systems 5, and Installation, Maintenance and Repair 7.

What this bank leaves out

Twenty questions need a drawing from the pool file and one repeats an earlier question, so 21 are held back. In 19 questions "of the above" reads "of these", because choices are shuffled here.

  • Key topics 2, 5 and 32 rest on one constant: the pool takes a radar mile, out and back, as 12.34 microseconds.
  • The 20 drawing questions held back here sit in key topics 7, 9, 10, 20, 21, 24, 26 and 45 of the FCC's pool file.

Questions and answers

How many questions are on Element 8, and how many can you miss?

Fifty, with 12 misses allowed: the pass mark on the FCC's examinations page is 38. That page gives no time limit, which is why Exam mode runs without a clock.

Does the General Radiotelephone Operator License need Element 8?

No. 47 CFR 13.201(b)(2) lists that license as Written Elements 1 and 3. Element 8 is only for the Ship Radar Endorsement. Element 3 practice and Element 1 practice have their own pages here.

Are these the questions on the real Element 8 exam?

The 50 exam questions come from this pool of 300, because 47 CFR 13.207(b) ties every question set to its element's pool. This bank follows the FCC's file as archived in March 2026 and leaves out 21 of the 300.

Is there an FCC Element 8 study guide PDF?

Yes, the FCC's own: its Element 8 pool is a PDF with the drawings beside their questions. A sheet printed from this page carries only the questions that need no drawing.

More tests

Show 7 more

Browse Radio and Aviation