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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

SelectAnswer
AZinc oxide
BMica
CBeryllium Oxide
DUranium Hexafluoride

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. - E1B03

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

SelectAnswer
A10 miles
B1 mile
C3 miles
D30 miles

4. - E1C10

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHz?

SelectAnswer
AAt least 63 dB below
BAt least 53 dB below
CAt least 43 dB below
DAt least 73 dB below

5. - E1D03

What is a space telecommand station?

SelectAnswer
AAn amateur station that transmits communications to initiate, modify or terminate functions of a space station
BAn amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
CAn amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
DAn amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites

6. - E1E01

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

SelectAnswer
AProviding amateur operator license examination preparation training materials
BNo expenses are authorized for reimbursement
CTeaching an amateur operator license examination preparation course
DPreparing, processing, administering, and coordinating an examination for an amateur radio operator license

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. - E2A02

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

SelectAnswer
ASignal position in the band is reversed
BAll these choices are correct
CDoppler shift is reduced because the uplink and downlink shifts are in opposite directions
DUpper sideband on the uplink becomes lower sideband on the downlink, and vice versa

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 identify the SSTV mode being used
DTo provide vertical synchronization

10. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

SelectAnswer
ARepeater contacts between U.S. club members
BContacts using tactical call signs
CContacts between a U.S. station and a non-U.S. station
DSpecial event contacts between stations in the U.S.

11. - E2D11

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

SelectAnswer
ALatitude and longitude
BRadio direction finding spectrum analysis
CPolar coordinates
DTime and frequency

12. - E2E06

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

SelectAnswer
A300 baud
B110 baud
C48 baud
D1200 baud

13. - E3A09

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

SelectAnswer
A220 MHz - 450 MHz
B1.8 MHz - 1.9 MHz
C28 MHz - 148 MHz
D10 MHz - 14 MHz

14. - E3B04

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

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

15. - E3C08

What does the space weather term G5 mean?

SelectAnswer
AVery low solar activity
BAn extreme geomagnetic storm
CWaning sunspot numbers
DModerate solar wind

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

SelectAnswer
AAntenna analyzers automatically tune your antenna for resonance
BAll these choices are correct
CAntenna analyzers display a time-varying representation of the modulation envelope
DAntenna analyzers do not need an external RF source

17. - E4B05

What three test loads are used to calibrate an RF vector network analyzer?

SelectAnswer
A50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
BShort circuit, open circuit, and resonant circuit
CShort circuit, open circuit, and 50 ohms
D50 ohms, 75 ohms, and 90 ohms

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

SelectAnswer
AMultiple frequencies can be received simultaneously if desired
BReceive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
CThe noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
DReceiver power consumption can be reduced when wider bandwidth is not required

19. - E4D08

What causes intermodulation in an electronic circuit?

SelectAnswer
ALack of neutralization
BPositive feedback
CToo little gain
DNonlinear circuits or devices

20. - E4E06

What is one type of electrical interference that might be caused by a nearby personal computer?

SelectAnswer
AThe appearance of unstable modulated or unmodulated signals at specific frequencies
BA loud AC hum in the audio output of your station receiver
CA whining type noise that continually pulses off and on
DA clicking noise at intervals of a few seconds

21. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

SelectAnswer
AReactance of either the inductance or capacitance multiplied by the resistance
BReactance of either the inductance or capacitance divided by the resistance
CResistance divided by the reactance of either the inductance or capacitance
DReactance of the inductance multiplied by the reactance of the capacitance

22. - E5B10

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

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

23. - E5C02

How are impedances described in polar coordinates?

SelectAnswer
ABy phase angle and magnitude
BBy X and R values
CBy real and imaginary parts
DBy Y and G values

24. - E5D13

How many watts are consumed in a circuit consisting of a 100-ohm resistor in series with a 100-ohm inductive reactance drawing 1 ampere?

SelectAnswer
A70.7 watts
B200 watts
C100 watts
D141.4 watts

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 cutoff frequency
BCorner frequency
CAlpha rejection frequency
DBeta cutoff frequency

26. - E6B01

What is the most useful characteristic of a Zener diode?

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

27. - E6C05

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

SelectAnswer
ALower power consumption
BLower distortion
CImmune to damage from static discharge
DDifferential output capability

28. - E6D12

What is inductor saturation?

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

29. - E6E07

What type of transmission line is used for connections to MMICs?

SelectAnswer
AMiniature coax
BCircular waveguide
CMicrostrip
DParallel wire

30. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

SelectAnswer
ACadmium Sulfide
BSelenium
CCopper oxide
DSilicon

31. - E7A11

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

SelectAnswer
AAssertive Logic
BReverse Logic
CNegative logic
DPositive Logic

32. - E7B11

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

SelectAnswer
ASelf bias
BOutput load resistor
CEmitter bypass
DFixed bias

33. - E7C05

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

SelectAnswer
AA Chebyshev filter
BAn active LC filter
CA passive op-amp filter
DA Butterworth filter

34. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

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

35. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

SelectAnswer
ATwo and four times the original frequency
BThe two input frequencies along with their sum and difference frequencies
C1.414 and 0.707 times the input frequency
DThe square root of the product of input frequencies

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

37. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E73 when R1 is 10 ohms and RF is 470 ohms?

SelectAnswer
A0.21
B24
C94
D47

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 inductance
BBias the crystal at a specified voltage
CBias the crystal at a specified current
DProvide the crystal with a specified parallel capacitance

39. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

SelectAnswer
ASpeech characteristics
BThe degree of carrier suppression
CThe frequency of the modulating signal
DAmplifier gain

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

SelectAnswer
A1/3
B3
C6000
D2000

41. - E8C10

How may data rate be increased without increasing bandwidth?

SelectAnswer
AUsing a more efficient digital code
BUsing forward error correction
CIncreasing analog-to-digital conversion resolution
DIt is impossible

42. - E8D01

Why are received spread spectrum signals resistant to interference?

SelectAnswer
AThe high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
BIf interference is detected by the receiver it will signal the transmitter to change frequencies
CThe receiver is always equipped with a digital blanker
DSignals not using the spread spectrum algorithm are suppressed in the receiver

43. - E9A13

What term describes station output, taking into account all gains and losses?

SelectAnswer
AEffective radiated power
BApparent power
CHalf-power bandwidth
DPower factor

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

SelectAnswer
AMutual impedance analysis
BGraphical analysis
CMethod of Moments
DCalculus differentiation with respect to physical properties

45. - E9C02

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

SelectAnswer
AOmni-directional
BA figure-8 broadside to the axis of the array
CCardioid
DA figure-8 end-fire along the axis of the array

46. - E9D05

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

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

47. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

SelectAnswer
ATo transform the antenna impedance to a higher value
BTo cancel the inductive reactance of the matching network
CTo provide a rejection notch that prevents the radiation of harmonics
DTo provide DC isolation between the feed line and the antenna

48. - E9F09

What is the approximate physical length of a foam polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 7.2 MHz?

SelectAnswer
A8.3 meters
B10.4 meters
C6.9 meters
D5.2 meters

49. - E9G03

Which of the following is often determined using a Smith chart?

SelectAnswer
ASatellite azimuth and elevation bearings
BImpedance and SWR values in transmission lines
CTrigonometric functions
DBeam headings and radiation patterns

50. - E9H09

What is a Pennant antenna?

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

Figure E7-1