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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
AAll these choices are correct
BThe body reacts to electromagnetic radiation from both the E and H fields
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. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

SelectAnswer
AThe control operator of the packet bulletin board station
BThe control operators of all the stations in the system
CThe control operators of all the stations in the system not authenticating the source from which they accept communications
DThe control operator of the originating station

3. - E1B02

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

SelectAnswer
A20 kHz
B15 kHz
C10 kHz
D3 kHz

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 Utilities Technology Council (UTC) of their call sign and coordinates of the station
COperators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
DA special endorsement must be requested from the FCC

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

SelectAnswer
A70 cm only
B70 cm and 33 cm
C70 cm and 13 cm
D33 cm and 13 cm

6. - E1E01

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

SelectAnswer
APreparing, processing, administering, and coordinating an examination for an amateur radio operator license
BNo expenses are authorized for reimbursement
CProviding amateur operator license examination preparation training materials
DTeaching an amateur operator license examination preparation course

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
A440 MHz - 450 MHz
B53 MHz - 54 MHz
C222 MHz - 223 MHz
D420 MHz - 430 MHz

8. - E2A02

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

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

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

SelectAnswer
A120
B90
C60
D30

10. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

SelectAnswer
ASend your full call sign once or twice
BSend only the last two letters of your call sign until you make contact
CSend your full call sign and grid square
DSend the call sign of the DX station three times, the words this is,then your call sign three times

11. - E2D06

Which of the following describes a method of establishing EME contacts?

SelectAnswer
ATime synchronous transmissions alternately from each station
BJudging optimum transmission times by monitoring beacons reflected from the moon
CHigh-speed CW identification to avoid fading
DStoring and forwarding digital messages

12. - E2E12

How do ALE stations establish contact?

SelectAnswer
AALE radios monitor an internet site for the frequency they are being paged on
BALE radios activate when they hear their signal echoed by back scatter
CALE radios send a constant tone code to establish a frequency for future use
DALE constantly scans a list of frequencies, activating the radio when the designated call sign is received

13. - E3A09

Which of the following frequency ranges is most suited for meteor scatter communications?

SelectAnswer
A28 MHz - 148 MHz
B220 MHz - 450 MHz
C1.8 MHz - 1.9 MHz
D10 MHz - 14 MHz

14. - E3B04

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

SelectAnswer
AIndependent waves created in the ionosphere that are elliptically polarized
BLong-path and short-path waves
CRefracted rays and reflected waves
DExtraordinary waves describe rare long-skip propagation compared to ordinary waves, which travel shorter distances

15. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the sun will cause disturbed conditions?

SelectAnswer
ASouthward
BNorthward
CWestward
DEastward

16. - E4A11

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

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

17. - E4B02

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

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

18. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

SelectAnswer
AThe reference voltage of the analog-to-digital converter
BOne-half the maximum sample rate
CThe maximum count value of the analog-to-digital converter
DOne-half the maximum sampling buffer size

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
B173.35 MHz and 139.40 MHz
C146.88 MHz and 146.34 MHz
D146.10 MHz and 147.30 MHz

20. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

SelectAnswer
ASignals that appear at one IF but not another
BSignals that appear across a wide bandwidth
CSignals that are constant at all IF levels
DSignals that have a sharply peaked frequency distribution

21. - E5A15

Which of the following increases Q for inductors and capacitors?

SelectAnswer
ALower reactance
BHigher self-resonant frequency
CLower losses
DLower self-resonant frequency

22. - E5B04

What is the time constant of a circuit having two 220-microfarad capacitors and two 1-megohm resistors, all in parallel?

SelectAnswer
A110 seconds
B220 seconds
C55 seconds
D440 seconds

23. - E5C04

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

SelectAnswer
AMaidenhead grid
BRectangular coordinates
CElliptical coordinates
DFaraday grid

24. - E5D08

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

SelectAnswer
A600 watts
B200 watts
C1600 watts
D1000 watts

25. - E6A01

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

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

26. - E6B01

What is the most useful characteristic of a Zener diode?

SelectAnswer
AA constant voltage drop under conditions of varying current
BA negative resistance region
CA constant current drop under conditions of varying voltage
DAn internal capacitance that varies with the applied voltage

27. - E6C03

What is tri-state logic?

SelectAnswer
ALow-power logic devices designed to operate at 3 volts
BLogic devices that utilize ternary math
CProprietary logic devices manufactured by Tri-State Devices
DLogic devices with 0, 1, and high-impedance output states

28. - E6D12

What is inductor saturation?

SelectAnswer
AThe ability of the inductor's core to store magnetic energy has been exceeded
BThe inductor windings are over-coupled
CAdjacent inductors become over-coupled
DThe inductor's voltage rating is exceeded causing a flashover

29. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

SelectAnswer
A10 ohms
B50 ohms
C300 ohms
D450 ohms

30. - E6F11

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

SelectAnswer
A0.1 V
B1.5 V
C0.5 V
D12 V

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

SelectAnswer
AIt produces logic 1 at its output if only one input is logic 1
BIt produces logic 0 at its output only if all inputs are logic 0
CIt produces logic 0 at its output if only one input is logic 1
DIt produces logic 1 at its output only if all inputs are logic 1

32. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

SelectAnswer
ABecause they are relatively close in frequency to the desired signal
BBecause they are relatively far in frequency from the desired signal
CBecause they maintain the sidebands, thus causing multiple duplicate signals
DBecause they invert the sidebands causing distortion

33. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

SelectAnswer
AAn active LC filter
BA Chebyshev filter
CA passive op-amp filter
DA Butterworth filter

34. - E7D08

What type of circuit is shown in Figure E7-2?

SelectAnswer
AMonostable multivibrator
BGrounded emitter amplifier
CSwitching voltage regulator
DLinear voltage regulator

35. - E7E04

What is one way a single-sideband phone signal can be generated?

SelectAnswer
ABy driving a product detector with a DSB signal
BBy using a balanced modulator followed by a filter
CBy using a reactance modulator followed by a mixer
DBy using a loop modulator followed by a mixer

36. - E7F12

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

SelectAnswer
AFIR filters can delay all frequency components of the signal by the same amount
BFIR filters can respond faster to impulses
CFIR filters are easier to implement for a given set of passband rolloff requirements
DAll these choices are correct

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

SelectAnswer
A0.23 volts
B-0.23 volts
C-2.3 volts
D2.3 volts

38. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

SelectAnswer
AThrough a capacitive divider
BThrough link coupling
CThrough a neutralizing capacitor
DThrough a tapped coil

39. - E8A10

What is the purpose of a low-pass filter used in conjunction with a digital-to-analog converter?

SelectAnswer
AAll these choices are correct
BRemove harmonics from the output caused by the discrete analog levels generated
CLower the input bandwidth to increase the effective resolution
DImprove accuracy by removing out-of-sequence codes from the input

40. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency?

SelectAnswer
AIt varies with the square root of the RF carrier frequency
BIt decreases as the RF carrier frequency increases
CIt increases as the RF carrier frequency increases
DIt does not depend on the RF carrier frequency

41. - E8C10

How may data rate be increased without increasing bandwidth?

SelectAnswer
AIt is impossible
BUsing a more efficient digital code
CUsing forward error correction
DIncreasing analog-to-digital conversion resolution

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

SelectAnswer
ABaudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
BBaudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
CBaudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
DBaudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

43. - E9A05

What is included in the total resistance of an antenna system?

SelectAnswer
ARadiation resistance plus space impedance
BRadiation resistance plus transmission resistance
CRadiation resistance plus loss resistance
DTransmission-line resistance plus radiation resistance

44. - E9B02

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

SelectAnswer
A36 dB
B18 dB
C14 dB
D24 dB

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

SelectAnswer
AThe front-to-back ratio decreases
BThe lobes align more in the direction of the wire
CThe lobes become more perpendicular to the wire
DThe vertical angle increases

46. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

SelectAnswer
AAs close to the transmitter as possible
BAt a voltage node
CAs low as possible on the vertical radiator
DNear the center of the vertical radiator

47. - E9E08

What is a use for a Wilkinson divider?

SelectAnswer
AIt is used to feed high-impedance antennas from a low-impedance source
BIt is used to feed low-impedance loads from a high-impedance source
CIt is used to divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance
DIt divides the operating frequency of a transmitter signal so it can be used on a lower frequency band

48. - E9F01

What is the velocity factor of a transmission line?

SelectAnswer
AThe index of shielding for coaxial cable
BThe ratio of the characteristic impedance of the line to the terminating impedance
CThe velocity of the wave in the transmission line divided by the velocity of light in a vacuum
DThe velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum

49. - E9G05

Which of the following is a common use for a Smith chart?

SelectAnswer
ADetermine the loss/100 feet of a transmission line, given the velocity factor and conductor materials
BDetermine the length and position of an impedance matching stub
CDetermine the gain of an antenna given the physical and electrical parameters
DDetermine the impedance of a transmission line, given the physical dimensions

50. - E9H09

What is a Pennant antenna?

SelectAnswer
AA four-element, high-gain vertical array invented by George Pennant
BA small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms
CA form of rhombic antenna terminated in a variable capacitor to provide frequency diversity
DA stealth antenna built to look like a flagpole

Figure E7-2

Figure E7-3

Figure E9-1