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

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1. - E0A08

What does SAR measure?

SelectAnswer
ASignal Amplification Rating
BThe rate of RF energy reflected from stationary terrain
CSynthetic Aperture Ratio of the human body
DThe rate at which RF energy is absorbed by the body

2. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

SelectAnswer
AThe exact lower band edge
B300 Hz above the lower band edge
C3 kHz above the lower band edge
D1 kHz above the lower band edge

3. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AA signal transmitted to prevent its detection by any station other than the intended recipient
BAn amateur station transmission made without the proper call sign identification
CAn emission outside the signal's necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
DAny transmitted signal that unintentionally interferes with another licensed radio station

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

SelectAnswer
A170 Hz
B2.8 kHz
C60 Hz
D1.5 kHz

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

6. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

SelectAnswer
AA sentence of up to one year in prison
BAll these choices are correct
CRevocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
DA fine of up to $1000 per occurrence

7. - E1F08

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

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

8. - E2A01

What is the direction of an ascending pass for an amateur satellite?

SelectAnswer
AFrom east to west
BFrom west to east
CFrom south to north
DFrom north to south

9. - E2B11

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

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

10. - E2C10

Why might a DX station state that they are listening on another frequency?

SelectAnswer
ATo improve operating efficiency by reducing interference
BBecause the DX station may be transmitting on a frequency that is prohibited to some responding stations
CTo separate the calling stations from the DX station
DAll these choices are correct

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

SelectAnswer
AConnect
BAcknowledgement
CDisconnect
DUnnumbered Information

12. - E2E06

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

SelectAnswer
A300 baud
B110 baud
C48 baud
D1200 baud

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 D layer
BThe F2 layer
CThe F1 layer
DThe E layer

14. - E3B07

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

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

15. - E3C13

What type of polarization is best for ground-wave propagation?

SelectAnswer
ACircular
BVertical
CHorizontal
DElliptical

16. - E4A04

How is the compensation of an oscilloscope probe typically adjusted?

SelectAnswer
AA square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
BA high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
CA DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
DA frequency standard is displayed and the probe is adjusted until the deflection time is accurate

17. - E4B02

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

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

18. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a superheterodyne HF or VHF communications receiver?

SelectAnswer
AFewer components in the receiver
BReduced drift
CEasier for front-end circuitry to eliminate image responses
DImproved receiver noise figure

19. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

SelectAnswer
A146.34 MHz and 146.61 MHz
B146.88 MHz and 146.34 MHz
C146.10 MHz and 147.30 MHz
D173.35 MHz and 139.40 MHz

20. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

SelectAnswer
ABy installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
BBy installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
CBy installing a noise suppression resistor and a blocking capacitor in both leads
DBy connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads

21. - E5A05

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

SelectAnswer
AMatching bandwidth is increased
BMatching bandwidth is decreased
CMatching range is increased
DIt has no effect on impedance matching

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. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

SelectAnswer
AVenn diagram
BPhasor diagram
CNear field diagram
DFar field diagram

24. - E5D03

What is microstrip?

SelectAnswer
AShort lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
BPrecision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
CMiniature coax used for low power applications
DLightweight transmission line made of common zip cord

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

SelectAnswer
AIn microwave circuits
BIn high-power audio circuits
CIn high-current rectifier circuits
DIn very low-frequency RF circuits

26. - E6B08

Which of the following is a Schottky barrier diode?

SelectAnswer
AThermionic emission diode
BElectrolytic rectifier
CPIN junction
DMetal-semiconductor junction

27. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

SelectAnswer
ALarge bypass capacitance is inherent
BBandwidth is very limited
CThe input switching threshold is about two times the power supply voltage
DThe input switching threshold is about one-half the power supply voltage

28. - E6D03

Which of the following is an aspect of the piezoelectric effect?

SelectAnswer
AMechanical deformation of material by the application of a magnetic field
BGeneration of electrical energy in the presence of light
CIncreased conductivity in the presence of light
DMechanical deformation of material by the application of a voltage

29. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

SelectAnswer
ARadial lead
BAxial lead
CTO-220
DSurface mount

30. - E6F04

What is the photovoltaic effect?

SelectAnswer
AThe conversion of electrical energy to mechanical energy
BThe conversion of voltage to current when exposed to light
CThe tendency of a battery to discharge when exposed to light
DThe conversion of light to electrical energy

31. - E7A08

What logical operation does an OR gate perform?

SelectAnswer
AIt produces logic 0 at its output if all inputs are logic 1
BIt produces logic 1 at its output if any or all inputs are logic 1
CIt produces logic 1 at its output if all inputs are logic 0
DIt only produces logic 0 at its output when all inputs are logic 1

32. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

SelectAnswer
AThe power transistor is at saturation or cutoff most of the time
BSwitching amplifiers use push-pull circuits
CLinear amplifiers have high gain resulting in higher harmonic content
DSwitching amplifiers operate at higher voltages

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 introduces transconductance to cancel the reactive part of impedance
CIt introduces negative resistance to cancel the resistive part of impedance
DIt cancels the reactive part of the impedance and changes the resistive part to a desired value

34. - E7D04

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

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

35. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
ATo remove third-order distortion products
BFor compatibility with transmitters using phase modulation
CFor higher efficiency
DTo reduce impulse noise reception

36. - E7F07

What function is performed by a Fast Fourier Transform?

SelectAnswer
AConverting digital signals to analog form
BConverting analog signals to digital form
CConverting digital signals from the time domain to the frequency domain
DConverting 8-bit data to 16-bit data

37. - E7G01

What is the typical output impedance of an op-amp?

SelectAnswer
AVery low
BVery high
C100 ohms
D1000 ohms

38. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

39. - E8A02

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

SelectAnswer
ALevel shifting
BHarmonic regeneration
CPhase reversal
DSuccessive approximation

40. - E8B07

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

SelectAnswer
AEME
BExtremely low-power contacts
COFDM signals are not allowed on amateur bands
DHigh-speed digital modes

41. - E8C07

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

SelectAnswer
A15.36 kHz
B4.8 kHz
C5.76 kHz
D9.6 kHz

42. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

SelectAnswer
AMore difficult to copy
BThe generation of key clicks
CLimits data speed
DThe generation of RF harmonics

43. - E9A01

What is an isotropic antenna?

SelectAnswer
AA horizontally polarized antenna used to compare Yagi antennas
BA theoretical, omnidirectional antenna used as a reference for antenna gain
CA spacecraft antenna used to direct signals toward Earth
DA grounded antenna used to measure Earth conductivity

44. - E9B03

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

SelectAnswer
A12 dB
B24 dB
C14 dB
D18 dB

45. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

SelectAnswer
AThe horizontal beamwidth increases in the uphill direction
BThe horizontal beamwidth decreases in the downhill direction
CThe main lobe takeoff angle increases in the downhill direction
DThe main lobe takeoff angle decreases in the downhill direction

46. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

SelectAnswer
ATo minimize losses
BTo swamp out harmonics
CTo minimize the Q
DTo lower the radiation angle

47. - E9E10

Which of these choices is an effective way to match an antenna with a 100-ohm feed point impedance to a 50-ohm coaxial cable feed line?

SelectAnswer
AInsert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
BConnect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
CInsert a 1/4-wavelength piece of 75-ohm coaxial cable transmission line in series between the antenna terminals and the 50-ohm feed cable
DConnect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna

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 higher velocity factor
BFoam dielectric has lower loss per unit of length
CAll these choices are correct
DFoam dielectric has lower safe operating voltage limits

49. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

SelectAnswer
ACoaxial-length circles
BStanding wave ratio circles
CRadiation-pattern circles
DAntenna-length circles

50. - E9H03

What is Receiving Directivity Factor (RDF)?

SelectAnswer
ARelative directivity compared to isotropic
BForward gain compared to average gain over the entire hemisphere
CRelative directivity compared to a dipole
DForward gain compared to the gain in the reverse direction

Figure E9-1