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

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1. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

SelectAnswer
A300 to 3000 MHz
B30 to 300 MHz
C3 to 30 MHz
D300 kHz to 3 MHz

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
A1 kHz above the lower band edge
B300 Hz above the lower band edge
C3 kHz above the lower band edge
DThe exact lower band edge

3. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

SelectAnswer
A3 miles
B10 miles
C1 mile
D30 miles

4. - E1C12

On what portion of the 630 meter band are phone emissions permitted?

SelectAnswer
AThe entire band
BOnly the bottom 3 kHz
CNone
DOnly the top 3 kHz

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

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

7. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

SelectAnswer
AIt was imported from a manufacturer in another country and was certificated by that country's government
BThe equipment dealer assembled it from a kit
CIt was imported from a manufacturer in a country that does not require certification of RF power amplifiers
DIt was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station

8. - E2A10

What type of satellite appears to stay in one position in the sky?

SelectAnswer
AGeostationary
BHEO
CLEO
DGeomagnetic

9. - E2B04

How is color information sent in analog SSTV?

SelectAnswer
AColor information is sent on a 2.8 kHz subcarrier
BColor is amplitude modulated on the frequency modulated intensity signal
CColor is sent in a color burst at the end of each line
DColor lines are sent sequentially

10. - E2C02

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

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

11. - E2D08

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

SelectAnswer
ADisconnect
BAcknowledgement
CConnect
DUnnumbered Information

12. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

SelectAnswer
ASelective fading has occurred
BOne of the signal filters is saturated
CThe mark and space signal have been inverted
DThe receiver has drifted 5 kHz from the desired receive frequency

13. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

SelectAnswer
AWind shear
BThe jet stream
CTemperature inversion
DDust devil

14. - E3B11

At what time of day can sporadic E propagation occur?

SelectAnswer
AOnly in hours of darkness
BOnly around sunset
CAny time
DOnly around sunset and sunrise

15. - E3C01

What does the radio communication term "ray tracing" describe?

SelectAnswer
AThe process in which an electronic display presents a pattern
BDetermining the radiation pattern from an array of antennas
CEvaluating high voltage sources for x-rays
DModeling a radio wave's path through the ionosphere

16. - E4A06

What is the effect of aliasing on a digital oscilloscope caused by setting the time base too slow?

SelectAnswer
AAll signals will have a DC offset
BExcessive blanking occurs, which prevents display of the signal
CA false, jittery low-frequency version of the signal is displayed
DCalibration of the vertical scale is no longer valid

17. - E4B07

What do the subscripts of S parameters represent?

SelectAnswer
AThe port or ports at which measurements are made
BFrequency order of the measurements
CRelative quality of the data
DThe relative time between measurements

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

SelectAnswer
AA narrow IF filter
BA front-end filter or pre-selector
CA properly adjusted product detector
DA notch filter

19. - E4D02

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

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

20. - E4E09

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

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

21. - E5A05

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

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

22. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

SelectAnswer
A76 degrees with the voltage leading the current
B14 degrees with the voltage lagging the current
C76 degrees with the voltage lagging the current
D14 degrees with the voltage leading the current

23. - E5C01

Which of the following represents capacitive reactance in rectangular notation?

SelectAnswer
A-jX
B+jX
CDelta
DOmega

24. - E5D03

What is microstrip?

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

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

SelectAnswer
ABase-to-emitter resistance of approximately 0.6 to 0.7 ohms
BBase-to-emitter voltage of approximately 6 to 7 volts
CBase-to-emitter voltage of approximately 0.6 to 0.7 volts
DBase-to-emitter resistance of approximately 6 to 7 ohms

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

SelectAnswer
ALow junction capacitance
BAbility to dissipate large amounts of power
CReverse bias controls its forward voltage drop
DExtremely high reverse breakdown voltage

27. - E6C07

What best describes a pull-up or pull-down resistor?

SelectAnswer
AA resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
BA resistor in a keying circuit used to reduce key clicks
CA resistor that ensures that an oscillator frequency does not drift
DA resistor connected to an op-amp output that prevents signals from exceeding the power supply voltage

28. - E6D13

What is the primary cause of inductor self-resonance?

SelectAnswer
ANon-linear core hysteresis
BInter-turn capacitance
CThe skin effect
DInductive kickback

29. - E6E12

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

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

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 measures the strength of a beam of light using analog to digital conversion
CA digital encryption device often used to encrypt spacecraft control signals
DA device that detects rotation of a control by interrupting a light source with a patterned wheel

31. - E7A06

What is a characteristic of a monostable multivibrator?

SelectAnswer
AIt maintains a constant output voltage, regardless of variations in the input voltage
BIt produces a continuous square wave oscillating between 1 and 0
CIt stores one bit of data in either a 0 or 1 state
DIt switches momentarily to the opposite binary state and then returns to its original state after a set time

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

33. - E7C05

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

SelectAnswer
AA Chebyshev filter
BA passive op-amp filter
CAn active LC filter
DA Butterworth filter

34. - E7D15

What is the purpose of a step-start circuit in a high-voltage power supply?

SelectAnswer
ATo compensate for variations of the incoming line voltage
BTo allow for remote control of the power supply
CTo provide a dual-voltage output for reduced power applications
DTo allow the filter capacitors to charge gradually

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

SelectAnswer
AAn FM generator circuit
BA circuit for filtering two closely adjacent signals
CAn automatic band-switching circuit
DA circuit for detecting FM signals

36. - E7F08

What is the function of decimation?

SelectAnswer
AReducing the effective sample rate by removing samples
BConverting data to binary code decimal form
CRemoving unnecessary significant digits
DAttenuating the signal

37. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-3 when R1 is 3300 ohms and RF is 47 kilohms?

SelectAnswer
A14
B28
C0.07
D7

38. - E7H12

Which of the following must be done to ensure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

SelectAnswer
AProvide the crystal with a specified parallel capacitance
BProvide the crystal with a specified parallel inductance
CBias the crystal at a specified voltage
DBias the crystal at a specified current

39. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all its harmonics?

SelectAnswer
AA sine wave
BA square wave
CA sawtooth wave
DA cosine wave

40. - E8B11

What is digital time division multiplexing?

SelectAnswer
ATwo or more data streams share the same channel by transmitting time of transmission as the sub-carrier
BTwo or more data streams are assigned to discrete sub-carriers on an FM transmitter
CTwo or more signals are quadrature modulated to increase bandwidth efficiency
DTwo or more signals are arranged to share discrete time slots of a data transmission

41. - E8C07

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

SelectAnswer
A9.6 kHz
B4.8 kHz
C5.76 kHz
D15.36 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. - E9A09

What is antenna efficiency?

SelectAnswer
ARadiation resistance divided by transmission resistance
BEffective radiated power divided by transmitter output
CTotal resistance divided by radiation resistance
DRadiation resistance divided by total resistance

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

SelectAnswer
A25 degrees
B75 degrees
C50 degrees
D30 degrees

45. - E9C08

What is a folded dipole antenna?

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

46. - E9D03

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

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

47. - E9E11

What is the primary purpose of phasing lines when used with an antenna having multiple driven elements?

SelectAnswer
AIt creates a low-angle radiation pattern
BIt prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
CIt ensures that each driven element operates in concert with the others to create the desired antenna pattern
DIt allows single-band antennas to operate on other bands

48. - E9F11

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

SelectAnswer
AAn inductive reactance
BA capacitive reactance
CThe same as the characteristic impedance of the line
DInfinite

49. - E9G02

What type of coordinate system is used in a Smith chart?

SelectAnswer
AVoltage lines and current chords
BResistance circles and reactance arcs
CResistance lines and reactance chords
DVoltage circles and current arcs

50. - E9H11

What feature of a cardioid pattern antenna makes it useful for direction finding?

SelectAnswer
ABroadband response
BHigh radiation angle
CA very sharp single null
DA very sharp peak

Figure E7-3

Figure E9-1