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

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1. - E0A01

What is the primary function of an external earth connection or ground rod?

SelectAnswer
AReduce RF current flow between pieces of equipment
BReduce RFI to telephones and home entertainment systems
CLightning protection
DReduce received noise

2. - E1A03

What is the maximum legal carrier frequency on the 20 meter band for transmitting USB AFSK digital signals having a 1 kHz bandwidth?

SelectAnswer
A14.100 MHz
B14.349 MHz
C14.070 MHz
D14.149 MHz

3. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

SelectAnswer
AAll amateur service frequencies authorized to the control operator
BMilitary Auxiliary Radio System (MARS) channels
CSpecific segments in the amateur service MF, HF, VHF and UHF bands
DSpecific local government channels

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

SelectAnswer
AAn environmental impact statement must be filed with the Department of the Interior
BOperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
CA special endorsement must be requested from the FCC
DOperators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

SelectAnswer
AA space station, beacon station, or telecommand station
BAll these choices are correct
CA message forwarding station or automatically controlled digital station
DA local repeater or linked repeater station

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

7. - E1F09

Which of the following conditions apply when transmitting spread spectrum emissions?

SelectAnswer
AThe transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions
BThe transmission must not be used to obscure the meaning of any communication
CAll these choices are correct
DA station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions

8. - E2A04

What is meant by the term mode? as applied to an amateur radio satellite?

SelectAnswer
AWhether the satellite is in a low earth or geostationary orbit
BThe satellite's uplink and downlink frequency bands
CThe satellite's orientation with respect to the Earth
DWhether the satellite is in a polar or equatorial orbit

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

SelectAnswer
ATransmitting on the abandoned TV channel 2
BTransmitting on channels shared with cable TV
CUsing converted satellite TV dishes
DUsing USB and demodulating the signal with a computer sound card

10. - E2C02

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

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

11. - E2D11

Which of the following data are used by the APRS network to communicate station location?

SelectAnswer
ATime and frequency
BRadio direction finding spectrum analysis
CLatitude and longitude
DPolar coordinates

12. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

SelectAnswer
APACTOR
BPSK31
CMT63
DRTTY

13. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

SelectAnswer
AWhen the moon is full
BWhen the MUF is above 30 MHz
CWhen the moon is at perigee
DWhen the moon is at apogee

14. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

SelectAnswer
A5000 miles
B7500 miles
C2500 miles
D1000 miles

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. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
ANetwork analyzer
BModulation monitor
CLogic analyzer
DBit error rate tester

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
A100 watts
B125 watts
C25 watts
D75 watts

18. - E4C12

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

SelectAnswer
ARAM speed used for data storage
BCPU register width in bits
CAnalog-to-digital converter sample width in bits
DAnti-aliasing input filter bandwidth

19. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

SelectAnswer
AA properly terminated circulator at the output of the repeater's transmitter
BUtilizing a Class D final amplifier
CA band-pass filter in the feed line between the transmitter and receiver
DUtilizing a Class C final amplifier

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
BFM signals can no longer be demodulated
CThe audio frequency bandwidth of the received signal might be compressed
DNearby signals may appear to be excessively wide even if they meet emission standards

21. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

SelectAnswer
AApproximately equal to inductive reactance
BHigh, as compared to the circuit resistance
CApproximately equal to capacitive reactance
DApproximately equal to circuit 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
A14 degrees with the voltage lagging the current
B14 degrees with the voltage leading the current
C76 degrees with the voltage leading the current
D76 degrees with the voltage lagging the current

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 7
BPoint 3
CPoint 1
DPoint 8

24. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

SelectAnswer
AIn all directions; omni-directional
BIn a direction opposite to the current
CIn a circle around the conductor
DIn the same direction as the current

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

SelectAnswer
A6
B4
C5
D2

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. - E6C01

What is the function of hysteresis in a comparator?

SelectAnswer
ATo increase the sensitivity
BTo allow the comparator to be used with AC input signals
CTo cause the output to change states continually
DTo prevent input noise from causing unstable output signals

28. - E6D01

Why should core saturation of an impedance matching transformer be avoided?

SelectAnswer
ARF susceptance would increase
BTemporary changes of the core permeability could result
CMagnetic flux would increase with frequency
DHarmonics and distortion could result

29. - E6E12

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

SelectAnswer
AEpoxy coating is conductive above 300 MHz
BExcessive lead length
CUnsuitable for combining analog and digital signals
DToo many pins

30. - E6F07

What is a solid-state relay?

SelectAnswer
AA device that uses semiconductors to implement the functions of an electromechanical relay
BA mechanical relay that latches in the on or off state each time it is pulsed
CA relay using transistors to drive the relay coil
DA semiconductor passive delay line

31. - E7A11

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

SelectAnswer
ANegative logic
BPositive Logic
CAssertive Logic
DReverse Logic

32. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

SelectAnswer
AWhere the load line intersects the voltage axis
BAt a point where the bias resistor equals the load resistor
CAt a point where the load line intersects the zero bias current curve
DApproximately halfway between saturation and cutoff

33. - E7C10

Which of the following filters would be the best choice for use in a 2 meter band repeater duplexer?

SelectAnswer
AA cavity filter
BAn L-C filter
CA DSP filter
DA crystal filter

34. - E7D14

What is the purpose of connecting equal-value resistors across power supply filter capacitors connected in series?

SelectAnswer
AProvide a minimum load on the supply
BDischarge the capacitors when voltage is removed
CEqualize the voltage across each capacitor
DAll these choices are correct

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 basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
DThe unmodulated bandwidth of the transmitted signal

36. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

SelectAnswer
AAn adaptive filter
BAn elliptical filter
CA Hilbert-transform filter
DA notch filter

37. - E7G01

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

SelectAnswer
AVery low
BVery high
C100 ohms
D1000 ohms

38. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

SelectAnswer
AUse a temperature-controlled high Q dielectric resonator
BAll these choices are correct
CUse a rubidium stabilized reference oscillator
DUse a GPS signal reference

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

SelectAnswer
AImmunity to out-of-sequence coding reduces spurious responses
BAll these choices are correct
CVery low power consumption decreases frequency drift
DVery high speed allows digitizing high frequencies

40. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

SelectAnswer
A0.3
B1000
C3000
D3

41. - E8C11

What is the relationship between symbol rate and baud?

SelectAnswer
ABaud is twice the symbol rate
BSymbol rate is only used for packet-based modes
CBaud is only used for RTTY
DThey are the same

42. - E8D06

What is the advantage of including parity bits in ASCII characters?

SelectAnswer
AFaster transmission rate
BThe signal can overpower interfering signals
CForeign language characters can be sent
DSome types of errors can be detected

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

SelectAnswer
A252 watts
B159 watts
C632 watts
D63.2 watts

44. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from a theoretical isotropic antenna, assuming each is driven by the same amount of power?

SelectAnswer
AThe total amount of radiation from the directional antenna is increased by the gain of the antenna
BThey are the same
CThe radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
DThe total amount of radiation from the directional antenna is stronger by its front-to-back ratio

45. - E9C08

What is a folded dipole antenna?

SelectAnswer
AA type of ground-plane antenna
BA dipole configured to provide forward gain
CA dipole one-quarter wavelength long
DA half-wave dipole with an additional parallel wire connecting its two ends

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

SelectAnswer
AThe front-to-back ratio decreases
BThe front-to-back ratio increases
CThe SWR is reduced
DThe frequency response is widened over the whole frequency band

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 omega match
DThe stub match

48. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

SelectAnswer
AThe surge impedance is higher in a parallel feed line
BThe characteristic impedance is higher in a parallel feed line
CSkin effect is less pronounced in the coaxial cable
DElectrical signals move more slowly in a coaxial cable than in air

49. - E9G01

Which of the following can be calculated using a Smith chart?

SelectAnswer
AImpedance along transmission lines
BAntenna radiation pattern
CRadio propagation
DRadiation resistance

50. - E9H03

What is Receiving Directivity Factor (RDF)?

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

Figure E5-1

Figure E6-1