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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
ABeryllium Oxide
BUranium Hexafluoride
CZinc oxide
DMica

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

SelectAnswer
A100 watts PEP effective radiated power relative to the gain of a half-wave dipole
B100 watts PEP effective radiated power relative to an isotropic radiator
C50 watts PEP effective radiated power relative to a dipole
D50 watts PEP effective radiated power relative to an isotropic radiator

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

4. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

SelectAnswer
AAll these choices are correct
BITU reciprocal license
CCEPT agreement
DIARP agreement

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

SelectAnswer
AOnly those of General, Advanced or Amateur Extra Class operators
BOnly those of Amateur Extra Class operators
CAny amateur station, subject to the privileges of the class of operator license held by the control operator
DAny amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau

6. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
AAll these choices are correct
BFriends of the VE
CEmployees of the VE
DRelatives of the VE as listed in the FCC rules

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
B440 MHz - 450 MHz
C420 MHz - 430 MHz
D222 MHz - 223 MHz

8. - E2A13

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

SelectAnswer
ADigipeating
BNode hopping
CMulti-satellite relaying
DStore-and-forward

9. - E2B12

What signals SSTV receiving software to begin a new picture line?

SelectAnswer
AElapsed time
BSpecific tone frequencies
CA two-tone signal
DSpecific tone amplitudes

10. - E2C02

Which of the following best describes the term self-spotting? in connection with HF contest operating?

SelectAnswer
AThe often-prohibited practice of posting one's own call sign and frequency on a spotting network
BThe acceptable practice of manually posting the call signs of stations on a spotting network
CA manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
DAn automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

11. - E2D03

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

SelectAnswer
APACTOR III
BOlivia
CMSK144
DJT65

12. - E2E13

Which of these digital modes has the fastest data throughput under clear communication conditions?

SelectAnswer
APSK31
BAMTOR
C170 Hz shift, 45 baud RTTY
D300 baud packet

13. - E3A04

What do Hepburn maps predict?

SelectAnswer
ASporadic E propagation
BLocations of auroral reflecting zones
CLikelihood of rain scatter along cold or warm fronts
DProbability of tropospheric propagation

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

SelectAnswer
AThey become elliptically polarized
BThey become phase locked
CThey are bent toward the magnetic poles
DThey become depolarized

15. - E3C15

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

SelectAnswer
ALong-path propagation is likely
BA temperature inversion has occurred
CA solar flare has occurred
DIncreased transequatorial propagation is likely

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

SelectAnswer
ASWR and frequency
BSWR and time
CRF amplitude and time
DRF amplitude and frequency

17. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

SelectAnswer
A125 watts
B25 watts
C75 watts
D100 watts

18. - E4C13

How does a narrow-band roofing filter affect receiver performance?

SelectAnswer
AIt improves intelligibility by using low Q circuitry to reduce ringing
BIt improves dynamic range by attenuating strong signals near the receive frequency
CIt improves sensitivity by reducing front end noise
DAll these choices are correct

19. - E4D06

What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

SelectAnswer
AIntermodulation
BAmplifier desensitization
CAdjacent channel interference
DNeutralization

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
AUse of braided shielding material
BCommon-mode currents on the shield and conductors
CTying all ground connections to a common point resulting in differential-mode currents in the shield
DLow inductance ground connections at both ends of the shield

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

SelectAnswer
AMaximum
BR/L
CL/R
DMinimum

22. - E5B03

How is impedance in polar form converted to an equivalent admittance?

SelectAnswer
ASquare the magnitude and subtract 90 degrees from the angle
BTake the reciprocal of the angle and change the sign of the magnitude
CTake the square root of the magnitude and add 180 degrees to the angle
DTake the reciprocal of the magnitude and change the sign of the angle

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

SelectAnswer
APoint 1
BPoint 7
CPoint 8
DPoint 3

24. - E5D14

What is reactive power?

SelectAnswer
AWattless, nonproductive power
BPower consumed in circuit Q
CPower lost because of capacitor leakage
DPower consumed in wire resistance in an inductor

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

SelectAnswer
A3
B2
C6
D1

26. - E6B11

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

SelectAnswer
AReverse voltage larger than the RF signal
BForward DC bias current
CA sub-harmonic pump signal
DCapacitance of an RF coupling capacitor

27. - E6C08

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

SelectAnswer
A3
B4
C2
D1

28. - E6D02

What is the equivalent circuit of a quartz crystal?

SelectAnswer
AMotional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
BMotional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
CMotional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
DMotional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

SelectAnswer
AToo many pins
BEpoxy coating is conductive above 300 MHz
CExcessive lead length
DUnsuitable for combining analog and digital signals

30. - E6F01

What absorbs the energy from light falling on a photovoltaic cell?

SelectAnswer
AHoles
BProtons
CElectrons
DPhotons

31. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

SelectAnswer
AA multiplexer
BAn XOR gate
CA flip-flop
DAn OR gate

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

SelectAnswer
AHigh filament voltage
BLow input impedance
CLow bandwidth
DHigh power gain

33. - E7C11

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

SelectAnswer
ANoise factor
BPassband ripple
CPhase response
DShape factor

34. - E7D01

How does a linear electronic voltage regulator work?

SelectAnswer
AThe control element duty cycle is proportional to the line or load conditions
BIt eliminates the need for a pass transistor
CThe conduction of a control element is varied to maintain a constant output voltage
DIt has a ramp voltage as its output

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 two input frequencies along with their sum and difference frequencies
CTwo and four times the original frequency
DThe square root of the product of input frequencies

36. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

SelectAnswer
AHigher data rate
BComplex phasor representations
CMore taps
DDouble-precision math routines

37. - E7G04

What is meant by the "op-amp input offset voltage"?

SelectAnswer
AThe output voltage of the op-amp minus its input voltage
BThe potential between the amplifier input terminals of the op-amp in an open loop condition
CThe differential input voltage needed to bring the open loop output voltage to zero
DThe difference between the output voltage of the op-amp and the input voltage required in the immediately following stage

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

SelectAnswer
AThrough link coupling
BThrough a quartz crystal
CThrough a neutralizing capacitor
DThrough a tapped coil

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

SelectAnswer
A100 to 1
B2.5 to 1
C25 to 1
D1 to 1

40. - E8B10

What is frequency division multiplexing?

SelectAnswer
ATwo or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
BTwo or more information streams are merged into a baseband, which then modulates the transmitter
CThe transmitted signal is divided into packets of information
DThe transmitted signal jumps from band to band at a predetermined rate

41. - E8C06

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

SelectAnswer
A0.3 kHz
B0.5 kHz
C1.0 kHz
D0.1 Hz

42. - E8D01

Why are received spread spectrum signals resistant to interference?

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

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
A78.7 watts
B286 watts
C420 watts
D1977 watts

44. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

SelectAnswer
A24 dB
B14 dB
C18 dB
D36 dB

45. - E9C09

Which of the following describes a G5RV antenna?

SelectAnswer
AA wide band dipole using shorted coaxial cable for the radiating elements and fed with aÿ4:1 balun
BA multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
CA phased array antenna consisting of multiple loops
DA multi-band trap antenna

46. - E9D01

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

SelectAnswer
A2 dB
B6 dB
C4 dB
D3 dB

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

SelectAnswer
ADouble-bazooka match
BHairpin match
CGamma match
DAll these choices are correct

48. - E9F08

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

SelectAnswer
AFoam dielectric has lower loss per unit of length
BAll these choices are correct
CFoam dielectric has higher velocity factor
DFoam dielectric has lower safe operating voltage limits

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 prime center with regard to the reactance axis
CReassigning reactance values with regard to the resistance axis
DReassigning resistance values with regard to the reactance axis

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

SelectAnswer
AHigh radiation angle
BA very sharp single null
CA very sharp peak
DBroadband response

Figure E5-1

Figure E6-1

Figure E6-3

Figure E9-1