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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
AUranium Hexafluoride
BBeryllium Oxide
CMica
DZinc oxide

2. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

SelectAnswer
AAny amateur license with an FCC Marine or Aircraft endorsement
BAny FCC-issued amateur license
CAn unrestricted Radiotelephone Operator Permit
DOnly General Class or higher amateur licenses

3. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

SelectAnswer
AThe amateur station must cease operation
BThe amateur station must cease operation on all frequencies below 30 MHz
CThe amateur station must avoid transmitting during certain hours on frequencies that cause the interference
DThe amateur station must cease operation on all frequencies above 30 MHz

4. - E1C06

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

SelectAnswer
AYou must append "/CEPT" to your call sign
BYou must bring a copy of FCC Public Notice DA 16-1048
CYou must identify in the official language of the country in which you are operating
DThe U.S. embassy must approve of your operation

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

6. - E1E09

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

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

7. - E1F08

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

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

8. - E2A01

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

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

9. - E2B10

What aspect of an analog slow-scan television signal encodes the brightness of the picture?

SelectAnswer
ASync frequency
BTone frequency
CSync amplitude
DTone amplitude

10. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

SelectAnswer
AAt the top of each band, usually in a segment reserved for contests
BIn the middle of each band, usually on the national calling frequency
CIn the middle of the band, usually 25 kHz above the national calling frequency
DIn the weak signal segment of the band, with most of the activity near the calling frequency

11. - E2D11

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

SelectAnswer
ALatitude and longitude
BTime and frequency
CRadio direction finding spectrum analysis
DPolar coordinates

12. - E2E04

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

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

13. - E3A02

What characterizes libration fading of an EME signal?

SelectAnswer
AA gradual loss of signal as the sun rises
BA slow change in the pitch of the CW signal
CA fluttery irregular fading
DThe returning echo is several hertz lower in frequency than the transmitted signal

14. - E3B01

What is transequatorial propagation?

SelectAnswer
APropagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
BPropagation between points located on the magnetic equator
CPropagation between points at the same latitude
DPropagation between a point on the equator and its antipodal point

15. - E3C11

What does VOACAP software model?

SelectAnswer
AVHF radio propagation
BAC voltage and impedance
CAC current and impedance
DHF propagation

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
BConnect the analyzer via a high-impedance transformer to the antenna
CLoosely couple the antenna and a dummy load to the analyzer
DConnect the antenna feed line directly to the analyzer's connector

17. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

SelectAnswer
AThere is an impedance mismatch between the antenna and feed line
BThere is possibly a short to ground in the feed line
CThere is more power going into the antenna
DThe transmitter is not properly neutralized

18. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and that uses a 455 kHz IF frequency?

SelectAnswer
A14.445 MHz
B14.755 MHz
C13.845 MHz
D15.210 MHz

19. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

SelectAnswer
ACross-modulation interference
BSquelch gain rollback
CDesensitization
DQuieting

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

SelectAnswer
AUse of braided shielding material
BCommon-mode currents on the shield and conductors
CTying all ground connections to a common point resulting in differential-mode currents in the shield
DLow inductance ground connections at both ends of the shield

21. - E5A01

What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

SelectAnswer
AResistance
BCapacitance
CConductance
DResonance

22. - E5B05

What happens to the magnitude of a pure reactance when it is converted to a susceptance?

SelectAnswer
AIt is shifted by 90 degrees
BIt is unchanged
CIt becomes the reciprocal
DThe sign is reversed

23. - E5C02

How are impedances described in polar coordinates?

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

24. - E5D06

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

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

25. - E6A02

Which of the following semiconductor materials contains excess free electrons?

SelectAnswer
AInsulated gate
BN-type
CBipolar
DP-type

26. - E6B06

Which of the following is a common use of a Schottky diode?

SelectAnswer
AAs a constant voltage reference in a power supply
BAs a VHF/UHF mixer or detector
CAs a variable capacitance in an automatic frequency control circuit
DAs a rectifier in high current power supplies

27. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

SelectAnswer
AThe comparator changes its output state
BThe feedback loop becomes unstable
CThe comparator enters latch-up
DThe IC input can be damaged

28. - E6D04

Which materials are commonly used as a core in an inductor?

SelectAnswer
APolystyrene and polyethylene
BCobalt and aluminum
CTeflon and Delrin
DFerrite and brass

29. - E6E10

What advantage does surface-mount technology offer at RF compared to using through-hole components?

SelectAnswer
ASmaller circuit area
BComponents have less parasitic inductance and capacitance
CShorter circuit-board traces
DAll these choices are correct

30. - E6F10

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

SelectAnswer
ACadmium Sulfide
BSelenium
CCopper oxide
DSilicon

31. - E7A06

What is a characteristic of a monostable multivibrator?

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

32. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

SelectAnswer
AUse a resistor in series with the emitter
BSelect transistors with high beta
CNeutralization
DAll these choices are correct

33. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

SelectAnswer
ATwo inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
BTwo capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
CAn inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
DA capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output

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 current source
CA series current source
DA shunt regulator

35. - E7E04

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

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

36. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

SelectAnswer
AIncoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
BA switching mixer is used to generate I and Q signals directly from the RF input
CIncoming RF is converted to a control voltage for a voltage controlled oscillator
DSoftware is converted from source code to object code during operation of the receiver

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

SelectAnswer
AIt increases linearly with increasing frequency
BIt decreases linearly with increasing frequency
CIt does not vary with frequency
DIt decreases logarithmically with increasing frequency

38. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

SelectAnswer
ANyquist limit noise
BBroadband noise
CDigital conversion noise
DSpurious signals at discrete frequencies

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
BImprove accuracy by removing out-of-sequence codes from the input
CRemove harmonics from the output caused by the discrete analog levels generated
DLower the input bandwidth to increase the effective resolution

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
A3
B1000
C3000
D0.3

41. - E8C09

Which digital code allows only one bit to change between sequential code values?

SelectAnswer
AGray code
BExcess 3 code
CBinary Coded Decimal Code
DExtended Binary Coded Decimal Interchange Code

42. - E8D09

What is considered an acceptable maximum IMD level for an idling PSK signal?

SelectAnswer
A+10 dB
B-20 dB
C+15 dB
D-30 dB

43. - E9A06

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

SelectAnswer
A2000 watts
B126 watts
C300 watts
D317 watts

44. - E9B09

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

SelectAnswer
AGraphical analysis
BCalculus differentiation with respect to physical properties
CMutual impedance analysis
DMethod of Moments

45. - E9C13

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with increasing height above ground?

SelectAnswer
AThe horizontal beamwidth decreases
BThe takeoff angle of the lowest elevation lobe decreases
CThe horizontal beamwidth increases
DThe takeoff angle of the lowest elevation lobe increases

46. - E9D12

Which of the following would provide the best RF ground for your station?

SelectAnswer
AAn electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
BA 50-ohm resistor connected to ground
CAn electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
DAn electrically short connection to a metal water pipe

47. - E9E11

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

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

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

SelectAnswer
A13.3 meters
B8.5 meters
C7.0 meters
D10.6 meters

49. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
ASWR
BPoints with constant reactance
CFrequency
DPoints with constant resistance

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

SelectAnswer
ALow loss coax transmission line is essential for good performance
BAll these choices are correct
CAtmospheric noise is so high that gain over a dipole is not important
DThey must be erected at least 1/2 wavelength above the ground to attain good directivity