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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

SelectAnswer
ANotify the originating station that the communication does not comply with FCC rules
BDiscontinue forwarding the communication as soon as you become aware of it
CDiscontinue forwarding all messages
DNotify the nearest FCC Field Engineer's office

2. - E1B01

Which of the following constitutes a spurious emission?

SelectAnswer
AAn emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
BAny transmitted signal that unintentionally interferes with another licensed radio station
CA signal transmitted to prevent its detection by any station other than the intended recipient
DAn amateur station transmission made at random without the proper call sign identification

3. - E1C02

What is meant by automatic control of a station?

SelectAnswer
ARemotely controlling a station's antenna pattern through a directional control link
BThe use of a control link between a control point and a locally controlled station
CThe use of devices and procedures for control so that the control operator does not have to be present at a control point
DA station operating with its output power controlled automatically

4. - E1D06

Which of the following is a requirement of a space station?

SelectAnswer
AThe space station must be capable of terminating transmissions by telecommand when directed by the FCC
BAll of these choices are correct
CThe space station must be capable of changing its orbit whenever such a change is ordered by NASA
DThe space station must cease all transmissions after 5 years

5. - E1E03

What is a Volunteer Examiner Coordinator?

SelectAnswer
AA person who has volunteered to administer amateur operator license examinations
BA person who has volunteered to prepare amateur operator license examinations
CThe person who has entered into an agreement with the FCC to be the VE session manager
DAn organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations

6. - E1F08

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

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

7. - E2A12

What is one way to predict the location of a satellite at a given time?

SelectAnswer
ABy subtracting the mean anomaly from the orbital inclination
BBy adding the mean anomaly to the orbital inclination
CBy means of the Doppler data for the specified satellite
DBy calculations using the Keplerian elements for the specified satellite

8. - E2B18

On which of the following frequencies is one likely to find FM ATV transmissions?

SelectAnswer
A29.6 MHz
B52.525 MHz
C1255 MHz
D14.230 MHz

9. - E2C11

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

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

10. - E2D07

What digital protocol is used by APRS?

SelectAnswer
AAMTOR
BAX.25
C802.11
DPACTOR

11. - E2E03

How is the timing of JT65 contacts organized?

SelectAnswer
AStations take turns on alternate days
BBy exchanging ACK/NAK packets
CIt depends on the lunar phase
DAlternating transmissions at 1 minute intervals

12. - E3A10

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

SelectAnswer
AWind shear
BDust devil
CThe jet stream
DTemperature inversion

13. - E3B09

At what time of year is Sporadic E propagation most likely to occur?

SelectAnswer
AAround the solstices, especially the winter solstice
BAround the equinoxes, especially the fall equinox
CAround the solstices, especially the summer solstice
DAround the equinoxes, especially the spring equinox

14. - E3C02

What is indicated by a rising A or K index?

SelectAnswer
ADecreasing disruption of the geomagnetic field
BIncreasing disruption of the geomagnetic field
CAn increase in the critical frequency
DHigher levels of solar UV radiation

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

SelectAnswer
AModulation monitor
BLogic analyzer
CBit error rate tester
DNetwork analyzer

16. - E4B11

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

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

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

SelectAnswer
AExcess output level
BDistortion
CLoss of sensitivity
DOverload

18. - 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
A146.10 MHz and 147.30 MHz
B146.88 MHz and 146.34 MHz
C146.34 MHz and 146.61 MHz
D173.35 MHz and 139.40 MHz

19. - E4E03

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

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

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

SelectAnswer
AFewer components are needed for the same performance
BParasitic effects are minimized
CInternal voltages and circulating currents increase
DPhase shift can become uncontrolled

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

SelectAnswer
A76 degrees with the voltage lagging the current
B14 degrees with the voltage lagging the current
C14 degrees with the voltage leading the current
D76 degrees with the voltage leading the current

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

SelectAnswer
AThe magnitude and phase of the point
BThe coordinate values along the horizontal and vertical axes
CThe tangent and cotangent values
DThe sine and cosine values

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

SelectAnswer
AIt is dissipated as heat in the circuit
BIt is dissipated as kinetic energy in the circuit
CIt is dissipated in the formation of inductive and capacitive fields
DIt is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated

24. - E6A01

In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?

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

25. - E6B12

What is one common use for PIN diodes?

SelectAnswer
AAs an RF switch
BAs a constant current source
CAs a constant voltage source
DAs a high voltage rectifier

26. - E6C09

What is a Programmable Logic Device (PLD)?

SelectAnswer
AA programmable collection of logic gates and circuits in a single integrated circuit
BAn algorithm for simulating logic functions during circuit design
CA device to control industrial equipment
DProgrammable equipment used for testing digital logic integrated circuits

27. - E6D13

What is the primary cause of inductor self-resonance?

SelectAnswer
AInter-turn capacitance
BThe skin effect
CNon-linear core hysteresis
DInductive kickback

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

SelectAnswer
AEnhanced sensitivity to light
BHigh-voltage insulating ability
CBetter dissipation of heat
DTo provide a low-pass frequency response

29. - E6F06

Which of these materials is affected the most by photoconductivity?

SelectAnswer
AAn ordinary metal
BA liquid semiconductor
CA heavy metal
DA crystalline semiconductor

30. - E7A11

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

SelectAnswer
ANegative logic
BReverse Logic
CPositive Logic
DAssertive Logic

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

SelectAnswer
ATransmission of spurious signals
BCreation of parasitic oscillations
CAll of these choices are correct
DLow efficiency

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

SelectAnswer
AOmega
BPi-L
CPi
DCascode

33. - E7D15

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

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

34. - 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 sum, difference and square root of the input frequencies

35. - E7F08

What is the function of decimation with regard to digital filters?

SelectAnswer
AAttenuating the signal
BRemoving unnecessary significant digits
CReducing the effective sample rate by removing samples
DConverting data to binary code decimal form

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

SelectAnswer
A0.03
B76
C1
D38

37. - E7H10

What information is contained in the lookup table of a direct digital frequency synthesizer?

SelectAnswer
AThe amplitude values that represent a sine-wave output
BThe phase relationship between a reference oscillator and the output waveform
CThe synthesizer frequency limits and frequency values stored in the radio memories
DThe phase relationship between a voltage-controlled oscillator and the output waveform

38. - E8A07

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

SelectAnswer
AThe frequency of the modulating signal
BThe amplifier gain
CThe degree of carrier suppression
DThe characteristics of the modulating signal

39. - E8B11

What is digital time division multiplexing?

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

40. - E8C01

How is Forward Error Correction implemented?

SelectAnswer
ABy varying the frequency shift of the transmitted signal according to a predefined algorithm
BBy transmitting extra data that may be used to detect and correct transmission errors
CBy the receiving station repeating each block of three data characters
DBy transmitting a special algorithm to the receiving station along with the data characters

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

SelectAnswer
AIntermodulation Distortion (IMD)
BRepeat Request Rate (RRR)
CBaud rate
DSignal to noise ratio

42. - E9A09

How is antenna efficiency calculated?

SelectAnswer
A(effective radiated power / transmitter output) x 100 percent
B(total resistance / radiation resistance) x 100 per cent
C(radiation resistance / transmission resistance) x 100 per cent
D(radiation resistance / total resistance) x 100 per cent

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

SelectAnswer
AElevation
BPolarization
CRadiation resistance
DAzimuth

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

SelectAnswer
AA figure-8 oriented along the axis of the array
BCardioid
COmni-directional
DA figure-8 broadside to the axis of the array

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

SelectAnswer
AIt is too sharply directional at lower frequencies
BIt might radiate harmonics
CIt must be neutralized
DIt radiates the harmonics and fundamental equally well

46. - E9E04

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

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

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

SelectAnswer
ACharacteristic impedance
BStanding wave ratio
CSurge impedance
DVelocity factor

48. - E9G10

What do the arcs on a Smith chart represent?

SelectAnswer
APoints with constant resistance
BSWR
CFrequency
DPoints with constant reactance

49. - E9H09

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

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

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

SelectAnswer
AUse an antenna modeling program to calculate field strength at accessible locations
BUse a hand calculator plus Smith-chart equations to calculate the fields
CUse a calibrated antenna analyzer
DAll of the choices are correct

Figure E7-4

Figure E9-2