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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
APolychlorinated biphenyls
BPolytetrafluoroethylene
CPolyethylene
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
ANotify the nearest FCC Field Engineers office
BAll these choices are correct
CNotify the originating station that the communication does not comply with FCC rules
DDiscontinue forwarding the communication as soon as you become aware of it

3. - E1B07

To what type of regulations does PRB-1 apply?

SelectAnswer
AUse of wireless devices in vehicles
BState and local zoning
CHomeowners associations
DFAA tower height limits

4. - E1C06

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

SelectAnswer
AYou must identify in the official language of the country in which you are operating
BYou must append "/CEPT" to your call sign
CYou must bring a copy of FCC Public Notice DA 16-1048
DThe U.S. embassy must approve of your operation

5. - E1D05

What must be posted at the station location of a station being operated by telecommand on or within 50 km of the earth's surface?

SelectAnswer
AA label with the name, address, and telephone number of the station licensee
BA label with the name, address, and telephone number of the control operator
CA photocopy of the station license
DAll these choices are correct

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

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
A420 MHz - 430 MHz
B440 MHz - 450 MHz
C53 MHz - 54 MHz
D222 MHz - 223 MHz

8. - E2A02

Which of the following occurs when a satellite is using an inverting linear transponder?

SelectAnswer
AUpper sideband on the uplink becomes lower sideband on the downlink, and vice versa
BDoppler shift is reduced because the uplink and downlink shifts are in opposite directions
CSignal position in the band is reversed
DAll these choices are correct

9. - E2B12

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

SelectAnswer
ASpecific tone frequencies
BElapsed time
CSpecific tone amplitudes
DA two-tone signal

10. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

SelectAnswer
A30 meters
B6 meters
C33 centimeters
D2 meters

11. - E2D05

What is one advantage of the JT65 mode?

SelectAnswer
AUses only a 65 Hz bandwidth
BEasily copied by ear if necessary
CPermits fast-scan TV transmissions over narrow bandwidth
DThe ability to decode signals which have a very low signal-to-noise ratio

12. - E2E06

What is the most common data rate used for HF packet?

SelectAnswer
A1200 baud
B300 baud
C48 baud
D110 baud

13. - E3A04

What do Hepburn maps predict?

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

14. - E3B04

What is meant by the terms "extraordinary" and "ordinary" waves?

SelectAnswer
ARefracted rays and reflected waves
BExtraordinary waves describe rare long-skip propagation compared to ordinary waves, which travel shorter distances
CLong-path and short-path waves
DIndependent waves created in the ionosphere that are elliptically polarized

15. - E3C12

How does the maximum range of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt peaks at roughly 14 MHz
BIt decreases
CIt increases
DIt stays the same

16. - E4A05

What is the purpose of the prescaler function on a frequency counter?

SelectAnswer
AIt prevents oscillation in a low-frequency counter circuit
BIt divides a higher frequency signal so a low-frequency counter can display the input frequency
CIt amplifies low-level signals for more accurate counting
DIt multiplies a higher frequency signal so a low-frequency counter can display the operating frequency

17. - E4B02

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

SelectAnswer
AThe full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
BWhen 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
CWhen used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
DWhen used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed

18. - E4C11

Why can an attenuator be used to reduce receiver overload on the lower frequency HF bands with little or no impact on signal-to-noise ratio?

SelectAnswer
AAtmospheric noise is generally greater than internally generated noise even after attenuation
BThe attenuator has a low-pass filter to increase the strength of lower frequency signals
CSignals are attenuated separately from the noise
DThe attenuator has a noise filter to suppress interference

19. - E4D07

Which of the following reduces the likelihood of receiver desensitization?

SelectAnswer
ADecrease the RF bandwidth of the receiver
BIncrease the receiver front end gain
CRaise the receiver IF frequency
DSwitch from fast AGC to slow AGC

20. - E4E10

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

SelectAnswer
AArcing contacts in a thermostatically controlled device
BA malfunctioning illuminated advertising display
CA defective doorbell or doorbell transformer inside a nearby residence
DAll these choices are correct

21. - E5A02

What is resonance in an LC or RLC circuit?

SelectAnswer
AThe lowest frequency that will pass current
BThe frequency at which the reactive impedance equals the resistive impedance
CThe highest frequency that will pass current
DThe frequency at which the capacitive reactance equals the inductive reactance

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
A14 degrees with the voltage lagging the current
B14 degrees with the voltage leading the current
C76 degrees with the voltage lagging the current
D76 degrees with the voltage leading the current

23. - E5C11

Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

SelectAnswer
APoint 8
BPoint 1
CPoint 7
DPoint 3

24. - E5D04

Why are short connections used at microwave frequencies?

SelectAnswer
ATo reduce phase shift along the connection
BTo increase neutralizing resistance
CTo increase compensating capacitance
DTo reduce noise figure

25. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

SelectAnswer
ABeta cutoff frequency
BAlpha rejection frequency
CCorner frequency
DAlpha cutoff frequency

26. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

SelectAnswer
AZener diode
BSilicon-controlled rectifier
CTunnel diode
DVaractor diode

27. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

SelectAnswer
AThe feedback loop becomes unstable
BThe comparator enters latch-up
CThe IC input can be damaged
DThe comparator changes its output state

28. - E6D11

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

SelectAnswer
AFerrite
BBrass
CCeramic
DPowdered iron

29. - E6E01

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

SelectAnswer
AHigher noise figures
BLower transconductance
CLower junction voltage drop
DHigher electron mobility

30. - E6F05

Which describes an optical shaft encoder?

SelectAnswer
AA device for generating RTTY signals by means of a rotating light source
BA device that detects rotation of a control by interrupting a light source with a patterned wheel
CA digital encryption device often used to encrypt spacecraft control signals
DA device that measures the strength of a beam of light using analog to digital conversion

31. - E7A10

What is a truth table?

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

32. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

SelectAnswer
AThe tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
BThe loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
CThe tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
DThe loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current

33. - E7C08

Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

SelectAnswer
AThe relative frequencies of the individual crystals
BThe DC voltage applied to the quartz crystal
CThe gain of the RF stage preceding the filter
DThe amplitude of the signals passing through the filter

34. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

SelectAnswer
AA shunt current source
BA shunt regulator
CA series current source
DA series regulator

35. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

SelectAnswer
AMixer blanking occurs
BAutomatic limiting occurs
CSpurious mixer products are generated
DA beat frequency is generated

36. - E7F08

What is the function of decimation?

SelectAnswer
AConverting data to binary code decimal form
BRemoving unnecessary significant digits
CAttenuating the signal
DReducing the effective sample rate by removing samples

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt decreases logarithmically with increasing frequency
BIt decreases linearly with increasing frequency
CIt increases linearly with increasing frequency
DIt does not vary with frequency

38. - E7H06

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

SelectAnswer
AColpitts and Hartley
BArmstrong and deForest
CPierce and Zener
DNegative feedback and balanced feedback

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

SelectAnswer
A8
B8 multiplied by the gain of the input amplifier
C256
D256 divided by the gain of the input amplifier

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

SelectAnswer
A3
B1/3
C2000
D6000

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

SelectAnswer
A5.76 kHz
B9.6 kHz
C15.36 kHz
D4.8 kHz

42. - E8D01

Why are received spread spectrum signals resistant to interference?

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

43. - E9A09

What is antenna efficiency?

SelectAnswer
ATotal resistance divided by radiation resistance
BRadiation resistance divided by transmission resistance
CRadiation resistance divided by total resistance
DEffective radiated power divided by transmitter output

44. - E9B08

What is the far field of an antenna?

SelectAnswer
AThe region where radiated power dissipates over a specified time period
BThe region where the shape of the antenna pattern is independent of distance
CThe region where radiated field strengths are constant
DThe region of the ionosphere where radiated power is not refracted

45. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus soil?

SelectAnswer
AThe low-angle radiation decreases
BThe low-angle radiation increases
CFewer vertical angle lobes will be present
DAdditional higher vertical angle lobes will appear

46. - E9D06

What happens to the SWR bandwidth when one or more loading coils are used to resonate an electrically short antenna?

SelectAnswer
AIt is increased
BIt is unchanged if the loading coil is located at the feed point
CIt is unchanged if the loading coil is located at a voltage maximum point
DIt is decreased

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

SelectAnswer
A75 ohms
B50 ohms
C62 ohms
D450 ohms

48. - E9F10

What impedance does a 1/8-wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AZero
BThe same as the characteristic impedance of the line
CA capacitive reactance
DAn inductive reactance

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

50. - E9H07

Why is RF attenuation used when direction-finding?

SelectAnswer
ATo narrow the receiver bandwidth
BTo prevent receiver overload which reduces pattern nulls
CTo compensate for isotropic directivity and the antenna effect of feed lines
DTo increase receiver sensitivity

Figure E5-1