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

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1. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

SelectAnswer
AThe body reacts to electromagnetic radiation from both the E and H fields
BAll these choices are correct
CE field and H field radiation intensity peaks can occur at different locations
DGround reflections and scattering make the field strength vary with location

2. - E1A07

What is the maximum power permitted on the 2200 meter band?

SelectAnswer
A50 watts PEP
B100 watts PEP
C1 watt EIRP (Equivalent isotropic radiated power)
D5 watts EIRP (Equivalent isotropic radiated power)

3. - E1B05

What is the National Radio Quiet Zone?

SelectAnswer
AAn area surrounding the National Radio Astronomy Observatory
BAn area in New Mexico surrounding the White Sands Test Area
CAn area in Florida surrounding Cape Canaveral
DAn area in Puerto Rico surrounding the Arecibo Radio Telescope

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
AIARP agreement
BCEPT agreement
CAll these choices are correct
DITU reciprocal license

5. - E1D04

Which of the following is required in the identification transmissions from a balloon-borne telemetry station?

SelectAnswer
AAll these choices are correct
BCall sign
CThe station's six-character Maidenhead grid locator
DThe output power of the balloon transmitter

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. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the government of Canada?

SelectAnswer
AFull privileges, up to and including those of the Amateur Extra Class license, on the 80, 40, 20, 15, and 10 meter bands
BThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Amateur Extra Class license privileges
CAll privileges of the Amateur Extra Class license
DNone, they must obtain a U.S. license

8. - E2A03

How is the signal inverted by an inverting linear transponder?

SelectAnswer
AThe signal is detected and remodulated on the reverse sideband
BThe signal is reduced to I and Q components and the Q component is filtered out
CThe signal is passed through a non-linear filter
DThe signal is passed through a mixer and the difference rather than the sum is transmitted

9. - E2B11

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

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

10. - E2C03

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

SelectAnswer
A6 meters
B2 meters
C30 meters
D33 centimeters

11. - E2D09

What type of modulation is used for JT65 contacts?

SelectAnswer
ARTTY
BMulti-tone AFSK
CPSK
DIEEE 802.11

12. - E2E02

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

SelectAnswer
AFinal Error Correction
BForward Error Correction
CFatal Error Correction
DFirst Error Correction

13. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

SelectAnswer
AThe E layer
BThe D layer
CThe F2 layer
DThe F1 layer

14. - E3B11

At what time of day can sporadic E propagation occur?

SelectAnswer
AOnly in hours of darkness
BAny time
COnly around sunset
DOnly around sunset and sunrise

15. - E3C12

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

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

16. - E4A11

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

SelectAnswer
AConnect the analyzer via a high-impedance transformer to the antenna
BLoosely couple the antenna and a dummy load to the analyzer
CConnect the antenna feed line directly to the analyzer's connector
DLoosely couple the analyzer near the antenna base

17. - E4B08

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

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

18. - E4C07

What does the MDS of a receiver represent?

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

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

SelectAnswer
ACross-modulation of the desired signal and insufficient audio power to operate the speaker
BSpurious signals caused by cross-modulation and desensitization from strong adjacent signals
COscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
DOscillator instability and severe audio distortion of all but the strongest received signals

20. - E4E09

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

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

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
A218.3 kHz
B15.7 kHz
C436.6 kHz
D31.4 kHz

22. - E5B10

What is the relationship between the AC current through an inductor and the voltage across an inductor?

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

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
A-jX
B+jX
COmega
DDelta

24. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

SelectAnswer
AIt is dissipated as heat in the circuit
BIt is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
CIt is dissipated as kinetic energy in the circuit
DIt is dissipated in the formation of inductive and capacitive fields

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
AAlpha rejection frequency
BCorner frequency
CBeta cutoff frequency
DAlpha cutoff frequency

26. - E6B06

Which of the following is a common use of a Schottky diode?

SelectAnswer
AAs a VHF/UHF mixer or detector
BAs a constant voltage reference in a power supply
CAs a variable capacitance in an automatic frequency control circuit
DAs a rectifier in high current power supplies

27. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

SelectAnswer
AImmune to damage from static discharge
BDifferential output capability
CLower distortion
DLower power consumption

28. - E6D05

What is one reason for using ferrite cores rather than powdered iron in an inductor?

SelectAnswer
AFerrite toroids generally require fewer turns to produce a given inductance value
BFerrite toroids generally have lower initial permeability
CFerrite toroids are easier to use with surface mount technology
DFerrite toroids generally have better temperature stability

29. - E6E08

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

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

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

SelectAnswer
A1.5 V
B0.5 V
C0.1 V
D12 V

31. - E7A11

What type of logic defines "1" as a high voltage?

SelectAnswer
ANegative logic
BAssertive Logic
CPositive Logic
DReverse Logic

32. - E7B11

In Figure E7-1, what is the purpose of R3?

SelectAnswer
ASelf bias
BFixed bias
COutput load resistor
DEmitter bypass

33. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

SelectAnswer
AReactive currents are dissipated in matched resistances
BIt cancels the reactive part of the impedance and changes the resistive part to a desired value
CIt introduces negative resistance to cancel the resistive part of impedance
DIt introduces transconductance to cancel the reactive part of impedance

34. - E7D02

What is a characteristic of a switching electronic voltage regulator?

SelectAnswer
AThe resistance of a control element is varied in direct proportion to the line voltage or load current
BIt gives a ramp voltage at its output
CThe controlled device's duty cycle is changed to produce a constant average output voltage
DIt is generally less efficient than a linear regulator

35. - E7E10

How does a diode envelope detector function?

SelectAnswer
ABy mixing signals with noise in the transition region of the diode
BBy rectification and filtering of RF signals
CBy sensing the change of reactance in the diode with respect to frequency
DBy breakdown of the Zener voltage

36. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
AIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
BIncoming RF is converted to a control voltage for a voltage controlled oscillator
CSoftware is converted from source code to object code during operation of the receiver
DA switching mixer is used to generate I and Q signals directly from the RF input

37. - E7G02

What is ringing in a filter?

SelectAnswer
APartial cancellation of the signal over a range of frequencies
BAn echo caused by a long time delay
CA reduction in high frequency response
DUndesired oscillations added to the desired signal

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

39. - E8A04

What is "dither" with respect to analog-to-digital converters?

SelectAnswer
AA small amount of noise added to the input signal to allow more precise representation of a signal over time
BAn abnormal condition where the converter cannot settle on a value to represent the signal
CAn error caused by irregular quantization step size
DA method of decimation by randomly skipping samples

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

SelectAnswer
A1.67
B0.167
C0.6
D60

41. - E8C07

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

SelectAnswer
A15.36 kHz
B4.8 kHz
C9.6 kHz
D5.76 kHz

42. - E8D07

What is a common cause of overmodulation of AFSK signals?

SelectAnswer
AExcessive numbers of retries
BExcessive transmit audio levels
CGround loops
DBit errors in the modem

43. - E9A09

What is antenna efficiency?

SelectAnswer
ARadiation resistance divided by total resistance
BRadiation resistance divided by transmission resistance
CTotal resistance divided by radiation resistance
DEffective radiated power divided by transmitter output

44. - E9B05

What type of antenna pattern is shown in Figure E9-2?

SelectAnswer
AAzimuth
BElevation
CPolarization
DRadiation resistance

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

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

SelectAnswer
AStack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
BStack two Yagis fed in phase to form an array with the respective elements in parallel planes
CArrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
DArrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase

47. - E9E05

How must an antenna's driven element be tuned to use a hairpin matching system?

SelectAnswer
AThe driven element reactance must be capacitive
BThe driven element reactance must be inductive
CThe driven element radiation resistance must be higher than the characteristic impedance of the transmission line
DThe driven element resonance must be lower than the operating frequency

48. - E9F04

What impedance does a 1/2-wavelength transmission line present to a generator when the line is shorted at the far end?

SelectAnswer
AVery high impedance
BThe same as the characteristic impedance of the line
CVery low impedance
DThe same as the output impedance of the generator

49. - E9G11

How are the wavelength scales on a Smith chart calibrated?

SelectAnswer
AIn fractions of transmission line electrical frequency
BIn fractions of antenna electrical frequency
CIn fractions of antenna electrical wavelength
DIn fractions of transmission line electrical wavelength

50. - E9H10

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

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

Figure E7-1

Figure E9-2