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

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1. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

SelectAnswer
APolytetrafluoroethylene
BPolyethylene
CPolychlorinated biphenyls
DPolymorphic silicon

2. - E1A09

What action or actions should you take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

SelectAnswer
AAll these choices are correct
BNotify the originating station that the communication does not comply with FCC rules
CDiscontinue forwarding the communication as soon as you become aware of it
DNotify the nearest FCC Field Engineers office

3. - E1B09

Which amateur stations may be operated under RACES rules?

SelectAnswer
AAny FCC-licensed amateur station except a Technician Class
BAny FCC-licensed amateur station certified by the responsible civil defense organization for the area served
COnly those club stations licensed to Amateur Extra Class operators
DAny FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

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

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

SelectAnswer
A70 cm and 33 cm
B70 cm and 13 cm
C33 cm and 13 cm
D70 cm only

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
BPhotocopy all examination documents and forward them to the FCC for processing
CAll these choices are correct
DThree VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

7. - E1F08

Which of the following types of amateur station communications are prohibited?

SelectAnswer
ACommunications transmitted for hire or material compensation, except as otherwise provided in the rules
BCommunications that have religious content
CCommunications in a language other than English
DCommunications that have political content, except as allowed by the Fairness Doctrine

8. - E2A06

What are Keplerian elements?

SelectAnswer
APhase reversing elements in a Yagi antenna
BHigh-emission heater filaments used in magnetron tubes
CEncrypting codes used for spread spectrum modulation
DParameters that define the orbit of a satellite

9. - E2B06

What is vestigial sideband modulation?

SelectAnswer
AAmplitude modulation in which one complete sideband and a portion of the other are transmitted
BA type of modulation in which one sideband is inverted
CSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
DNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier

10. - E2C12

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

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

11. - E2D03

Which of the following digital modes is especially useful for EME communications?

SelectAnswer
AMSK144
BJT65
COlivia
DPACTOR III

12. - E2E01

Which of the following types of modulation is common for data emissions below 30 MHz?

SelectAnswer
ASpread spectrum
BFSK
CDTMF tones modulating an FM signal
DPulse modulation

13. - E3A02

What characterizes libration fading of an EME signal?

SelectAnswer
AA slow change in the pitch of the CW signal
BA fluttery irregular fading
CA gradual loss of signal as the sun rises
DThe returning echo is several hertz lower in frequency than the transmitted signal

14. - E3B03

What is the best time of day for transequatorial propagation?

SelectAnswer
AMorning
BNoon
CLate at night
DAfternoon or early evening

15. - E3C15

What might be indicated by a sudden rise in radio background noise across a large portion of the HF spectrum?

SelectAnswer
AA temperature inversion has occurred
BIncreased transequatorial propagation is likely
CLong-path propagation is likely
DA solar flare has occurred

16. - E4A06

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

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

17. - E4B02

What is the significance of voltmeter sensitivity expressed in ohms per volt?

SelectAnswer
AWhen used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
BWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
CThe full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
DWhen used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test

18. - E4C12

Which of the following has the largest effect on an SDR receiver's dynamic range?

SelectAnswer
AAnti-aliasing input filter bandwidth
BRAM speed used for data storage
CCPU register width in bits
DAnalog-to-digital converter sample width in bits

19. - E4D08

What causes intermodulation in an electronic circuit?

SelectAnswer
AToo little gain
BNonlinear circuits or devices
CPositive feedback
DLack of neutralization

20. - E4E09

What undesirable effect can occur when using an IF noise blanker?

SelectAnswer
AReceived audio in the speech range might have an echo effect
BNearby signals may appear to be excessively wide even if they meet emission standards
CFM signals can no longer be demodulated
DThe audio frequency bandwidth of the received signal might be compressed

21. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

SelectAnswer
AReactance of either the inductance or capacitance divided by the resistance
BReactance of the inductance multiplied by the reactance of the capacitance
CResistance divided by the reactance of either the inductance or capacitance
DReactance of either the inductance or capacitance multiplied by the resistance

22. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A76 degrees with the voltage leading the current
B14 degrees with the voltage leading the current
C76 degrees with the voltage lagging the current
D14 degrees with the voltage lagging the current

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

SelectAnswer
AThe X axis represents the magnitude and the Y axis represents the phase angle
BThe X axis represents the reactive component and the Y axis represents the resistive component
CThe X axis represents the phase angle and the Y axis represents the magnitude
DThe X axis represents the resistive component and the Y axis represents the reactive component

24. - E5D07

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

SelectAnswer
A1.42 mW
B252 W
C704 W
D355 W

25. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

SelectAnswer
AOnly N-type semiconductor material can conduct current
BHoles in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
CExcess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
DOnly P-type semiconductor material can conduct current

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

SelectAnswer
AReverse bias controls its forward voltage drop
BAbility to dissipate large amounts of power
CLow junction capacitance
DExtremely high reverse breakdown voltage

27. - E6C10

In Figure E6-3, what is the schematic symbol for a NOR gate?

SelectAnswer
A4
B2
C1
D3

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

SelectAnswer
ACeramic
BBrass
CPowdered iron
DFerrite

29. - E6E08

How is power supplied to the most common type of MMIC?

SelectAnswer
AMMICs require no operating bias
BDirectly to the bias voltage (VCC IN) lead
CThrough a resistor and/or RF choke connected to the amplifier output lead
DThrough a capacitor and RF choke connected to the amplifier input lead

30. - E6F06

Which of these materials is most commonly used to create photoconductive devices?

SelectAnswer
AAn ordinary metal
BA liquid semiconductor
CA crystalline semiconductor
DA heavy metal

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 1
DIt produces logic 0 at its output only when all inputs are logic 0

32. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

SelectAnswer
ABecause they are relatively far in frequency from the desired signal
BBecause they maintain the sidebands, thus causing multiple duplicate signals
CBecause they are relatively close in frequency to the desired signal
DBecause they invert the sidebands causing distortion

33. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AA passive op-amp filter
BAn active LC filter
CA Chebyshev filter
DA Butterworth filter

34. - E7D09

What is the main reason to use a charge controller with a solar power system?

SelectAnswer
APrevention of battery damage due to overcharge
BMatching of day and night charge rates
CControl of electrolyte levels during battery discharge
DPrevention of battery undercharge

35. - E7E07

What is meant by the term "baseband" in radio communications?

SelectAnswer
AThe lowest frequency band that the transmitter or receiver covers
BThe frequency range occupied by a message signal prior to modulation
CThe unmodulated bandwidth of the transmitted signal
DThe basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency

36. - E7F04

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

SelectAnswer
AMixing products are converted to voltages and subtracted by adder circuits
BA frequency synthesizer removes the unwanted sidebands
CVarying quartz crystal characteristics emulated in digital form
DSignals are combined in quadrature phase relationship

37. - E7G05

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

SelectAnswer
AIncrease both gain and Q
BRestrict Q but increase gain
CRestrict gain but increase Q
DRestrict both gain and Q

38. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

SelectAnswer
ANegative feedback and balanced feedback
BArmstrong and deForest
CPierce and Zener
DColpitts and Hartley

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

SelectAnswer
ASuccessive approximation
BHarmonic regeneration
CPhase reversal
DLevel shifting

40. - E8B07

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

SelectAnswer
AEME
BOFDM signals are not allowed on amateur bands
CHigh-speed digital modes
DExtremely low-power contacts

41. - E8C04

What technique minimizes the bandwidth of a PSK31 signal?

SelectAnswer
AUse of sinusoidal data pulses
BZero-sum character encoding
CUse of trapezoidal data pulses
DReed-Solomon character encoding

42. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
ASignals not using the spread spectrum algorithm are suppressed in the receiver
BThe receiver is always equipped with a digital blanker
CIf interference is detected by the receiver it will signal the transmitter to change frequencies
DThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered

43. - E9A08

What is antenna bandwidth?

SelectAnswer
AThe angle formed between two imaginary lines drawn through the element ends
BThe angle between the half-power radiation points
CThe frequency range over which an antenna satisfies a performance requirement
DAntenna length divided by the number of elements

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AMethod of Moments
BMutual impedance analysis
CGraphical analysis
DCalculus differentiation with respect to physical properties

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

SelectAnswer
AThe lobes become more perpendicular to the wire
BThe vertical angle increases
CThe lobes align more in the direction of the wire
DThe front-to-back ratio decreases

46. - E9D01

How much does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

SelectAnswer
A4 dB
B2 dB
C6 dB
D3 dB

47. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

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

48. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

SelectAnswer
ALower velocity factor
BLower loss
CHigher SWR
DSmaller reflection coefficient

49. - E9G05

Which of the following is a common use for a Smith chart?

SelectAnswer
ADetermine the loss/100 feet of a transmission line, given the velocity factor and conductor materials
BDetermine the length and position of an impedance matching stub
CDetermine the gain of an antenna given the physical and electrical parameters
DDetermine the impedance of a transmission line, given the physical dimensions

50. - E9H05

What is the main drawback of a small wire-loop antenna for direction finding?

SelectAnswer
AIt has a bidirectional pattern
BIt has no clearly defined null
CIt is practical for use only on VHF and higher bands
DAll these choices are correct

Figure E6-3