Anonymous User

Hamboozler

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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
AReduce received noise
BReduce RF current flow between pieces of equipment
CLightning protection
DReduce RFI to telephones and home entertainment systems

2. - E1A03

What is the maximum legal carrier frequency on the 20 meter band for transmitting USB AFSK digital signals having a 1 kHz bandwidth?

SelectAnswer
A14.349 MHz
B14.100 MHz
C14.070 MHz
D14.149 MHz

3. - E1B12

What must the control operator of a repeater operating in the 70 cm band do if a radiolocation system experiences interference from that repeater?

SelectAnswer
ACease operation or make changes to the repeater to mitigate the interference
BReduce the repeater antenna HAAT (Height Above Average Terrain)
CAll these choices are correct
DFile an FAA NOTAM (Notice to Airmen) with the repeater system's ERP, call sign, and six-character grid locator

4. - E1C14

How long must an operator wait after filing a notification with the Utilities Technology Council (UTC) before operating on the 2200 meter or 630 meter band?

SelectAnswer
AOperators may not operate until a test signal has been transmitted in coordination with the local power company
BOperators may operate after 30 days, providing they have not been told that their station is within 1 km of PLC systems using those frequencies
COperations may commence immediately, and may continue unless interference is reported by the UTC
DOperators must not operate until approval is received

5. - E1D10

Which amateur stations are eligible to be telecommand stations of space stations (subject to the privileges of the class of operator license held by the control operator of the station)?

SelectAnswer
AAny amateur station so designated by the ITU
BAny amateur station designated by NASA
CAll these choices are correct
DAny amateur station so designated by the space station licensee

6. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

SelectAnswer
AIssue the examinee the new or upgrade license
BAll these choices are correct
CThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements
DPhotocopy all examination documents and forward them to the FCC for processing

7. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

SelectAnswer
A53 MHz - 54 MHz
B222 MHz - 223 MHz
C440 MHz - 450 MHz
D420 MHz - 430 MHz

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

SelectAnswer
ATo upload operational software for the transponder
BTo store digital messages in the satellite for later download by other stations
CTo delay download of telemetry between satellites
DTo relay messages between satellites

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

SelectAnswer
ATo provide vertical synchronization
BTo identify the call sign of the station transmitting
CTo lock the color burst oscillator in color SSTV images
DTo identify the SSTV mode being used

10. - E2C12

What technique do individual nodes use to form a mesh network?

SelectAnswer
AActing as store-and-forward digipeaters
BDiscovery and link establishment protocols
CCustom code plugs for the local trunking systems
DForward error correction and Viterbi codes

11. - E2D01

Which of the following digital modes is designed for meteor scatter communications?

SelectAnswer
AWSPR
BHellschreiber
CAPRS
DMSK144

12. - E2E02

What do the letters FEC mean as they relate to digital operation?

SelectAnswer
AFatal Error Correction
BForward Error Correction
CFinal Error Correction
DFirst Error Correction

13. - E3A04

What do Hepburn maps predict?

SelectAnswer
ALocations of auroral reflecting zones
BSporadic E propagation
CProbability of tropospheric propagation
DLikelihood of rain scatter along cold or warm fronts

14. - E3B12

What is the primary characteristic of chordal hop propagation?

SelectAnswer
ASignals reflected back toward the transmitting station
BPropagation across the geomagnetic equator
CSuccessive ionospheric refractions without an intermediate reflection from the ground
DPropagation away from the great circle bearing between stations

15. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
AAn increase in the critical frequency
BIncreasing disruption of the geomagnetic field
CHigher levels of solar UV radiation
DDecreasing disruption of the geomagnetic field

16. - E4A06

What is the effect of aliasing on a digital oscilloscope caused by setting the time base too slow?

SelectAnswer
AExcessive blanking occurs, which prevents display of the signal
BCalibration of the vertical scale is no longer valid
CA false, jittery low-frequency version of the signal is displayed
DAll signals will have a DC offset

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

SelectAnswer
AModulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
BModulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter
CModulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
DModulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer

18. - E4C07

What does the MDS of a receiver represent?

SelectAnswer
AThe maximum detectable spectrum
BThe multiplex distortion stability
CThe minimum discernible signal
DThe meter display sensitivity

19. - E4D01

What is meant by the blocking dynamic range of a receiver?

SelectAnswer
AThe minimum difference in dB between the levels of two FM signals that will cause one signal to block the other
BThe difference in dB between the noise floor and the third-order intercept point
CThe minimum difference in dB between two signals which produce third-order intermodulation products greater than the noise floor
DThe difference in dB between the noise floor and the level of an incoming signal that will cause 1 dB of gain compression

20. - E4E08

What current flows equally on all conductors of an unshielded multi-conductor cable?

SelectAnswer
ACommon-mode current
BReactive current only
CReturn current
DDifferential-mode current

21. - E5A05

What is the result of increasing the Q of an impedance-matching circuit?

SelectAnswer
AMatching bandwidth is decreased
BMatching range is increased
CIt has no effect on impedance matching
DMatching bandwidth is increased

22. - E5B02

What letter is commonly used to represent susceptance?

SelectAnswer
AG
BB
CX
DY

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
AOmega
BDelta
C+jX
D-jX

24. - E5D15

What is the power factor of an RL circuit having a 45-degree phase angle between the voltage and the current?

SelectAnswer
A0.866
B1.0
C0.707
D0.5

25. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

SelectAnswer
ATo reduce the chance of static damage to the gate
BTo keep the gate voltage within specifications and prevent the device from overheating
CTo protect the substrate from excessive voltages
DTo provide a voltage reference for the correct amount of reverse-bias gate voltage

26. - E6B08

Which of the following is a Schottky barrier diode?

SelectAnswer
AElectrolytic rectifier
BPIN junction
CThermionic emission diode
DMetal-semiconductor junction

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

SelectAnswer
A4
B1
C3
D2

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

SelectAnswer
AToroidal cores confine most of the magnetic field within the core material
BToroidal cores have lower Q characteristics
CToroidal cores make it easier to couple the magnetic energy into other components
DToroidal cores exhibit greater hysteresis

29. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

SelectAnswer
AA total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
BLow leakage doubly insulated package
CTwo chips in each package (Dual In Package)
DPackage mounts in a direct inverted position

30. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

SelectAnswer
AIt stays the same
BIt increases
CIt becomes unstable
DIt decreases

31. - E7A10

What is a truth table?

SelectAnswer
AA table of logic symbols that indicate the logic states of an op-amp
BA table of logic symbols that indicate the high logic states of an op-amp
CA list of inputs and corresponding outputs for a digital device
DA diagram showing logic states when the digital device output is true

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

SelectAnswer
ALow bandwidth
BLow input impedance
CHigh filament voltage
DHigh power gain

33. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

SelectAnswer
AIt is a high-pass filter
BIt is a notch filter
CIt is a low-pass filter
DIt is a band-pass filter

34. - E7D10

What is the primary reason that a high-frequency switching type high-voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

SelectAnswer
AIt uses a large power factor compensation capacitor to recover power from the unused portion of the AC cycle
BThe high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
CIt uses a diode bridge rectifier for increased output
DThe inverter design does not require any output filtering

35. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

SelectAnswer
A1.414 and 0.707 times the input frequency
BThe square root of the product of input frequencies
CTwo and four times the original frequency
DThe two input frequencies along with their sum and difference frequencies

36. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

SelectAnswer
AA notch filter
BAn elliptical filter
CAn adaptive filter
DA Hilbert-transform filter

37. - E7G05

How can unwanted ringing and audio instability be prevented in an op-amp RC audio filter circuit?

SelectAnswer
ARestrict both gain and Q
BRestrict gain but increase Q
CIncrease both gain and Q
DRestrict Q but increase gain

38. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

SelectAnswer
AThrough a capacitive divider
BThrough a neutralizing capacitor
CThrough link coupling
DThrough a tapped coil

39. - E8A05

What of the following instruments would be the most accurate for measuring the RMS voltage of a complex waveform?

SelectAnswer
AAn absorption wave meter
BA grid dip meter
CA true-RMS calculating meter
DA D'Arsonval meter

40. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

SelectAnswer
AEME
BHigh-speed digital modes
CExtremely low-power contacts
DOFDM signals are not allowed on amateur bands

41. - E8C06

What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

SelectAnswer
A0.3 kHz
B1.0 kHz
C0.5 kHz
D0.1 Hz

42. - E8D05

What is the most common method of reducing key clicks?

SelectAnswer
AHigh-pass filters at the transmitter output
BReduce keying waveform rise and fall times
CLow-pass filters at the transmitter output
DIncrease keying waveform rise and fall times

43. - E9A02

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

SelectAnswer
A420 watts
B78.7 watts
C286 watts
D1977 watts

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

SelectAnswer
A50 degrees
B25 degrees
C75 degrees
D30 degrees

45. - E9C10

Which of the following describes a Zepp antenna?

SelectAnswer
AAn end-fed dipole antenna
BA vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
CAn omni-directional antenna commonly used for satellite communications
DA dipole constructed from zip cord

46. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

SelectAnswer
ATo increase the SWR bandwidth
BTo lower the losses
CTo lower the Q
DTo cancel capacitive reactance

47. - E9E11

What is the primary purpose of phasing lines when used with an antenna having multiple driven elements?

SelectAnswer
AIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
BIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
CIt allows single-band antennas to operate on other bands
DIt creates a low-angle radiation pattern

48. - E9F13

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

SelectAnswer
AVery low impedance
BVery high impedance
CThe same as the characteristic impedance of the transmission line
DThe same as the generator output impedance

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

SelectAnswer
AResistance and reactance
BReactance and voltage
CResistance and voltage
DVoltage and impedance

50. - E9H10

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

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

Figure E6-3

Figure E9-1