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US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - 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
A3 kHz above the lower band edge
BThe exact lower band edge
C1 kHz above the lower band edge
D300 Hz above the lower band edge

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

SelectAnswer
AThe location is near an area of political conflict
BThe location is of geographical or horticultural importance
CThe location is in an ITU Zone designated for coordination with one or more foreign governments
DThe location is of environmental importance or significant in American history, architecture, or culture

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

SelectAnswer
AUnder automatic control there is no control operator
BUnder automatic control the control operator is not required to be present at the control point
CUnder local control there is no control operator
DUnder local control a control operator is not required to be present at a control point

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

SelectAnswer
AOnly the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
BAll HF bands
COnly the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
DOnly the 40 m, 20 m, 17 m, 15 m and 10 m bands

5. - E1E08

To which of the following examinees may a VE not administer an examination?

SelectAnswer
ARelatives of the VE as listed in the FCC rules
BAll of these choices are correct
CEmployees of the VE
DFriends of the VE

6. - 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 Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
BAll privileges of the Extra Class license
CThe operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
DNone, they must obtain a U.S. license

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

SelectAnswer
AA circularly polarized antenna
BAn isotropic antenna
CA log-periodic dipole array
DA linearly polarized antenna

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

SelectAnswer
ALuminance
BHue
CChroma
DSpectral Intensity

9. - E2C08

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

SelectAnswer
ASpecial event contacts between stations in the U.S.
BRepeater contacts between U.S. club members
CContacts using tactical call signs
DContacts between a U.S. station and a non-U.S. station

10. - E2D07

What digital protocol is used by APRS?

SelectAnswer
A802.11
BAX.25
CPACTOR
DAMTOR

11. - E2E04

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

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

12. - E3A12

What is the cause of auroral activity?

SelectAnswer
AMeteor showers concentrated in the extreme northern and southern latitudes
BThe interaction in the F2 layer between the solar wind and the Van Allen belt
CA low sunspot level combined with tropospheric ducting
DThe interaction in the E layer of charged particles from the Sun with the Earth's magnetic field

13. - E3B02

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

SelectAnswer
A2500 miles
B7500 miles
C1000 miles
D5000 miles

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

SelectAnswer
AIt peaks at roughly 14 MHz
BIt stays the same
CIt decreases
DIt increases

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

SelectAnswer
AA time-domain reflectometer
BA spectrum analyzer
CA logic analyzer
DA wattmeter

16. - 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
A125 watts
B100 watts
C75 watts
D25 watts

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

SelectAnswer
AIt reduces receiver sensitivity
BIt limits the receiver's ability to receive strong signals
CIt can cause strong signals on nearby frequencies to interfere with reception of weak signals
DIt decreases receiver third-order intermodulation distortion dynamic range

18. - E4D13

Which of the following can cause receiver desensitization?

SelectAnswer
AAudio bias adjusted too high
BAudio gain adjusted too low
CStrong adjacent channel signals
DSquelch gain misadjusted

19. - E4E06

What is a major cause of atmospheric static?

SelectAnswer
AThunderstorms
BGeomagnetic storms
CMeteor showers
DSolar radio frequency emissions

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

SelectAnswer
AIt is at a minimum
BIt is at a maximum
CIt equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
DIt equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance

21. - E5B12

What is admittance?

SelectAnswer
AThe turns ratio of a transformer
BThe term for the gain of a field effect transistor
CThe unit used for Q factor
DThe inverse of impedance

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

SelectAnswer
AElliptical coordinates
BMaidenhead grid
CFaraday grid
DPolar coordinates

23. - E5D16

What is the power factor of an R-L circuit having a 30 degree phase angle between the voltage and the current?

SelectAnswer
A1.73
B0.577
C0.5
D0.866

24. - E6A05

What is the alpha of a bipolar junction transistor?

SelectAnswer
AThe change of base current with respect to collector current
BThe change of collector current with respect to gate current
CThe change of collector current with respect to emitter current
DThe change of collector current with respect to base current

25. - E6B08

Which of the following describes a type of semiconductor diode?

SelectAnswer
AMetal-semiconductor junction
BThermionic emission diode
CCMOS-field effect
DElectrolytic rectifier

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

SelectAnswer
A3
B1
C4
D2

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

SelectAnswer
ASteel-core toroids
BElectrolytic capacitors
CFerrite beads
DButterworth filters

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

SelectAnswer
ASilicon
BSilicon nitride
CGallium nitride
DSilicon dioxide

29. - E6F14

Which of the following is true of LCD displays?

SelectAnswer
AAll of these choices are correct
BThey are hard to view in high ambient light conditions
CThey may be hard view through polarized lenses
DThey only display alphanumeric symbols

30. - E7A11

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

SelectAnswer
ANegative logic
BReverse Logic
CAssertive Logic
DPositive Logic

31. - E7B11

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

SelectAnswer
AFixed bias
BEmitter bypass
CSelf bias
DOutput load resistor

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

SelectAnswer
AIt is a high-pass filter
BIt is a notch filter
CIt is a band-pass filter
DIt is a low-pass filter

33. - E7D08

What type of circuit is shown in Figure E7-3?

SelectAnswer
ALinear voltage regulator
BSwitching voltage regulator
CGrounded emitter amplifier
DEmitter follower

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

SelectAnswer
ATo reduce impulse noise reception
BTo remove third-order distortion products
CFor higher efficiency
DFor compatibility with transmitters using phase modulation

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

SelectAnswer
AHigher data rate
BDouble-precision math routines
CComplex phasor representations
DMore taps

36. - E7G04

What is meant by the term op-amp input offset voltage?

SelectAnswer
AThe differential input voltage needed to bring the open loop output voltage to zero
BThe difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
CThe potential between the amplifier input terminals of the op-amp in an open loop condition
DThe output voltage of the op-amp minus its input voltage

37. - E7H13

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

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

38. - E8A10

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

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

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

SelectAnswer
A2.14
B0.214
C47
D0.47

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

SelectAnswer
ABinary Coded Decimal Code
BGray code
CExcess 3 code
DExtended Binary Coded Decimal Interchange Code

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

SelectAnswer
ABinary phase-shift keying
BFrequency hopping
CDirect sequence
DPhase compandored spread spectrum

42. - E9A02

What antenna has no gain in any direction?

SelectAnswer
AQuarter-wave vertical
BIsotropic antenna
CHalf-wave dipole
DYagi

43. - E9B03

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

SelectAnswer
A14 dB
B18 dB
C12 dB
D24 dB

44. - 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 vertical angle increases
DThe lobes become more perpendicular to the wire

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

SelectAnswer
AThe radiation resistance decreases and the capacitive reactance increases
BThe radiation resistance decreases and the capacitive reactance decreases
CThe radiation resistance increases and the capacitive reactance decreases
DThe radiation resistance increases and the capacitive reactance increases

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

SelectAnswer
AInsert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
BConnect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
CInsert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable
DConnect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

SelectAnswer
A0.2 meters
B2.3 meters
C3.5 meters
D20 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

SelectAnswer
AReassigning reactance values with regard to the resistance axis
BReassigning prime center with regard to the reactance axis
CReassigning resistance values with regard to the reactance axis
DReassigning impedance values with regard to the prime center

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

SelectAnswer
AA vertical antenna coupled to a feed line through an inductive loop of wire
BA large circularly polarized antenna
COne or more turns of wire wound in the shape of a large open coil
DA small coil of wire tightly wound around a toroidal ferrite core

50. - 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
AMica
BBeryllium Oxide
CUranium Hexafluoride
DZinc oxide

Figure E6-5

Figure E7-1

Figure E7-3

Figure E9-1