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US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

SelectAnswer
AEach transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
BOnly commercial transmitters
COnly the most powerful transmitter
DEach transmitter operating with a duty cycle greater than 50 percent

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

SelectAnswer
AAt the lowest frequency of the channel
BAt the highest frequency of the channel
COn any frequency where the signal's sidebands are within the channel
DAt the center frequency of the channel

3. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historic Places?

SelectAnswer
AA form FSD-15 must be submitted to the Department of the Interior
BAn Environmental Assessment must be submitted to the FCC
CA proposal must be submitted to the National Park Service
DA letter of intent must be filed with the Environmental Protection Agency

4. - E1C10

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHz?

SelectAnswer
AAt least 73 dB below
BAt least 43 dB below
CAt least 63 dB below
DAt least 53 dB below

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

SelectAnswer
A2 watts
B5 watts
C1 watt
D100 watts

6. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

SelectAnswer
AThe prospective VE obtains accreditation from the FCC
BThe procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
CThe amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
DEach General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted

7. - E1F10

Who may be the control operator of an auxiliary station?

SelectAnswer
AAny licensed amateur operator
BOnly Technician, General, Advanced or Amateur Extra Class operators
COnly Amateur Extra Class operators
DOnly General, Advanced or Amateur Extra Class operators

8. - E2A08

Why should effective radiated power to a satellite that uses a linear transponder be limited?

SelectAnswer
ATo avoid reducing the downlink power to all other users
BTo prevent creating errors in the satellite telemetry
CTo avoid interfering with terrestrial QSOs
DTo prevent the satellite from emitting out-of-band signals

9. - E2B04

How is color information sent in analog SSTV?

SelectAnswer
AColor is sent in a color burst at the end of each line
BColor is amplitude modulated on the frequency modulated intensity signal
CColor lines are sent sequentially
DColor information is sent on a 2.8 kHz subcarrier

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

SelectAnswer
A/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
BNo additional indicator is required
C/ followed by the ARRL Section of the remote station
D/R# where # is the district of the remote station

11. - E2D04

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

SelectAnswer
AAPRS
BUltrasonics
CDoppler shift of beacon signals
DBandwidth compressed LORAN

12. - E2E07

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

SelectAnswer
AAll these choices are correct
BYour transmit frequency is incorrect
CThe protocol version you are using is not supported by the digital station
DAnother station you are unable to hear is using the frequency

13. - E3A05

Tropospheric propagation of microwave signals often occurs in association with what phenomenon?

SelectAnswer
ALightning discharges
BGrayline
CWarm and cold fronts
DSprites and jets

14. - E3B05

Which amateur bands typically support long-path propagation?

SelectAnswer
AOnly 30 meters to 10 meters
B6 meters to 2 meters
C160 meters to 10 meters
DOnly 160 meters to 40 meters

15. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

SelectAnswer
AD-region skip
BDownward bending due to density variations in the atmosphere
CDue to the Doppler effect
DE-region skip

16. - E4A11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

SelectAnswer
ALoosely couple the antenna and a dummy load to the analyzer
BConnect the analyzer via a high-impedance transformer to the antenna
CLoosely couple the analyzer near the antenna base
DConnect the antenna feed line directly to the analyzer's connector

17. - E4B08

Which of the following can be used to measure the Q of a series-tuned circuit?

SelectAnswer
AThe bandwidth of the circuit's frequency response
BThe frequency shift
CThe inductance to capacitance ratio
DThe resonant frequency of the circuit

18. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

SelectAnswer
A-155 dBm
B-148 dBm
C-164 dBm
D-174 dBm

19. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

SelectAnswer
AA pair of 1 mW input signals will produce a third-order intermodulation product that is 40 dB stronger than the input signal
BSignals less than 40 dBm will not generate audible third-order intermodulation products
CThe receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
DA pair of 40 dBm input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of the input signals

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

SelectAnswer
ABroadband white noise
BAll these choices are correct
CPower line noise
DIgnition noise

21. - E5A12

What is the half-power bandwidth of a resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

SelectAnswer
A436.6 kHz
B218.3 kHz
C15.7 kHz
D31.4 kHz

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

SelectAnswer
ACurrent leads voltage by 90 degrees
BVoltage and current are in phase
CVoltage and current are 180 degrees out of phase
DVoltage leads current by 90 degrees

23. - E5C06

What does the impedance 50-j25 represent?

SelectAnswer
A25 ohms resistance in series with 50 ohms inductive reactance
B50 ohms resistance in series with 25 ohms inductive reactance
C25 ohms resistance in series with 50 ohms capacitive reactance
D50 ohms resistance in series with 25 ohms capacitive reactance

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

SelectAnswer
ATo maintain component lifetime
BTo avoid unwanted inductive reactance
CAll these choices are correct
DTo increase the thermal time constant

25. - E6A06

What is the beta of a bipolar junction transistor?

SelectAnswer
AThe breakdown voltage of the base to collector junction
BThe frequency at which the current gain is reduced to 0.707
CThe change in collector current with respect to base current
DThe switching speed

26. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

SelectAnswer
AA sub-harmonic pump signal
BReverse voltage larger than the RF signal
CForward DC bias current
DCapacitance of an RF coupling capacitor

27. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AA logic circuit that can be modified during use
BA programmable collection of logic gates and circuits in a single integrated circuit
CProgrammable equipment used for testing digital logic integrated circuits
DA type of transistor whose gain can be changed by digital logic circuits

28. - E6D07

What is current in the primary winding of a transformer called if no load is attached to the secondary?

SelectAnswer
ADirect current
BMagnetizing current
CStabilizing current
DExcitation current

29. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

SelectAnswer
A-20 dBm
B-10 dB
C44 dBm
D2 dB

30. - E6F07

What is a solid-state relay?

SelectAnswer
AA relay using transistors to drive the relay coil
BA device that uses semiconductors to implement the functions of an electromechanical relay
CA semiconductor passive delay line
DA mechanical relay that latches in the on or off state each time it is pulsed

31. - E7A07

What logical operation does a NAND gate perform?

SelectAnswer
AIt produces logic 1 at its output only when all inputs are logic 1
BIt produces logic 0 at its output if some but not all inputs are logic 1
CIt produces logic 0 at its output only when all inputs are logic 0
DIt produces logic 0 at its output only when all inputs are logic 1

32. - E7B06

Which of the following amplifier types reduces even-order harmonics?

SelectAnswer
AClass C
BPush-push
CPush-pull
DClass AB

33. - E7C11

Which of the following describes a receiving filter's ability to reject signals occupying an adjacent channel?

SelectAnswer
AShape factor
BNoise factor
CPassband ripple
DPhase response

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

SelectAnswer
AMinimum input voltage for rated power dissipation
BMaximum that the output voltage may decrease at rated load
CMaximum output voltage drops when the input voltage is varied over its specified range
DMinimum input-to-output voltage required to maintain regulation

35. - E7E01

Which of the following can be used to generate FM phone emissions?

SelectAnswer
AA reactance modulator on the oscillator
BA balanced modulator on the audio amplifier
CA balanced modulator on the oscillator
DA reactance modulator on the final amplifier

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

SelectAnswer
ASignals are combined in quadrature phase relationship
BVarying quartz crystal characteristics emulated in digital form
CMixing products are converted to voltages and subtracted by adder circuits
DA frequency synthesizer removes the unwanted sidebands

37. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 1800 ohms and RF is 68 kilohms?

SelectAnswer
A38
B76
C1
D0.03

38. - E7H12

Which of the following must be done to ensure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

SelectAnswer
ABias the crystal at a specified current
BProvide the crystal with a specified parallel capacitance
CBias the crystal at a specified voltage
DProvide the crystal with a specified parallel inductance

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

SelectAnswer
APeak envelope power
BTotal harmonic distortion
CReciprocal mixing
DPower factor

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

SelectAnswer
AA bandwidth compression technique using Fourier transforms
BA digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
CA frequency modulation technique that uses non-harmonically related frequencies
DA digital mode for narrow-band, slow-speed transmissions

41. - E8C03

Why should phase-shifting of a PSK signal be done at the zero crossing of the RF signal?

SelectAnswer
ATo minimize bandwidth
BTo improve carrier suppression
CTo simplify modulation
DAll these choices are correct

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

SelectAnswer
AExcessive transmit audio levels
BGround loops
CExcessive numbers of retries
DBit errors in the modem

43. - E9A04

Which of the following factors affect the feed point impedance of an antenna?

SelectAnswer
AThe settings of an antenna tuner at the transmitter
BTransmission line length
CThe input power level
DAntenna height

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

SelectAnswer
A28 dB
B15 dB
C3 dB
D38 dB

45. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

SelectAnswer
A300 ohms
B450 ohms
C50 ohms
D72 ohms

46. - E9D12

Which of the following would provide the best RF ground for your station?

SelectAnswer
AAn electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
BA 50-ohm resistor connected to ground
CAn electrically short connection to a metal water pipe
DAn electrically short connection to 3 or 4 interconnected ground rods driven into the Earth

47. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

SelectAnswer
AThe stub match
BThe epsilon match
CThe gamma match
DThe delta match

48. - E9F12

What impedance does a 1/4-wavelength transmission line present to a generator when the line is open at the far end?

SelectAnswer
AThe same as the characteristic impedance of the line
BThe same as the input impedance to the generator
CVery high impedance
DVery low impedance

49. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning impedance values with regard to the prime center
BReassigning reactance values with regard to the resistance axis
CReassigning resistance values with regard to the reactance axis
DReassigning prime center with regard to the reactance axis

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

SelectAnswer
ABy reducing the permeability of the loop shield
BBy increasing the number of turns and/or the area
CBy utilizing high impedance wire for the coupling loop
DBy winding adjacent turns in opposing directions

Figure E7-3