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?

Select	Answer
A	Discontinue forwarding all messages
B	Notify the nearest FCC Field Engineer's office
C	Discontinue forwarding the communication as soon as you become aware of it
D	Notify the originating station that the communication does not comply with FCC rules

2. - E1B03

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

Select	Answer
A	30 miles
B	1 mile
C	3 miles
D	10 miles

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Business-related messages for non-profit organizations
B	All of these choices are correct
C	Communications incidental to the purpose of the amateur service and remarks of a personal nature
D	Messages intended for connection to users of the maritime satellite service

4. - E1D06

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

Select	Answer
A	All of these choices are correct
B	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
C	The space station must cease all transmissions after 5 years
D	The space station must be capable of terminating transmissions by telecommand when directed by the FCC

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations
B	The person who has entered into an agreement with the FCC to be the VE session manager
C	A person who has volunteered to prepare amateur operator license examinations
D	A person who has volunteered to administer amateur operator license examinations

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	222 MHz - 223 MHz
B	440 MHz - 450 MHz
C	420 MHz - 430 MHz
D	53 MHz - 54 MHz

7. - E2A12

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

Select	Answer
A	By means of the Doppler data for the specified satellite
B	By subtracting the mean anomaly from the orbital inclination
C	By adding the mean anomaly to the orbital inclination
D	By calculations using the Keplerian elements for the specified satellite

8. - E2B13

How many lines are commonly used in each frame of an amateur slow-scan color television picture?

Select	Answer
A	128 or 256
B	30 or 60
C	180 or 360
D	60 or 100

9. - E2C10

Why might a DX station state that they are listening on another frequency?

Select	Answer
A	To improve operating efficiency by reducing interference
B	To separate the calling stations from the DX station
C	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
D	All of these choices are correct

10. - E2D11

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

Select	Answer
A	Latitude and longitude
B	Polar coordinates
C	Time and frequency
D	Radio direction finding spectrum analysis

11. - E2E06

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

Select	Answer
A	1200 baud
B	300 baud
C	110 baud
D	48 baud

12. - E3A09

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

Select	Answer
A	10 MHz - 14 MHz
B	28 MHz - 148 MHz
C	1.8 MHz - 1.9 MHz
D	220 MHz - 450 MHz

13. - E3B02

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

Select	Answer
A	7500 miles
B	2500 miles
C	1000 miles
D	5000 miles

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Duration of long-delayed echoes
B	Geomagnetic field stability
C	Critical frequency for vertical transmissions
D	Direction and strength of the interplanetary magnetic field

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Logic analyzer
B	Modulation monitor
C	Network analyzer
D	Bit error rate tester

16. - E4B11

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

Select	Answer
A	Loosely couple the analyzer near the antenna base
B	Connect the antenna feed line directly to the analyzer's connector
C	Connect the analyzer via a high-impedance transformer to the antenna
D	Loosely couple the antenna and a dummy load to the analyzer

17. - E4C01

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

Select	Answer
A	It decreases receiver third-order intermodulation distortion dynamic range
B	It limits the receiver's ability to receive strong signals
C	It reduces receiver sensitivity
D	It can cause strong signals on nearby frequencies to interfere with reception of weak signals

18. - E4D07

Which describes the most significant effect of an off-frequency signal when it is causing cross-modulation interference to a desired signal?

Select	Answer
A	A reduction in apparent signal strength
B	The off-frequency unwanted signal is heard in addition to the desired signal
C	A large increase in background noise
D	The desired signal can no longer be heard

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Ignition noise
B	Broadband white noise
C	All of these choices are correct
D	Power line noise

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

Select	Answer
A	23.5 kHz
B	7.12 kHz
C	7.12 MHz
D	23.5 MHz

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	G
B	X
C	B
D	Y

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

Select	Answer
A	A negative real part
B	A positive real part
C	A negative phase angle
D	A positive phase angle

23. - E5D16

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

Select	Answer
A	0.866
B	0.577
C	1.73
D	0.5

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of base current with respect to collector current
B	The change of collector current with respect to base current
C	The change of collector current with respect to emitter current
D	The change of collector current with respect to gate current

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Reverse bias
B	Forward bias
C	Zero bias
D	Inductive bias

26. - E6C10

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

Select	Answer
A	3
B	2
C	4
D	1

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Direct current
B	Stabilizing current
C	Magnetizing current
D	Excitation current

28. - E6E03

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

Select	Answer
A	Silicon nitride
B	Silicon dioxide
C	Gallium nitride
D	Silicon

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
B	A display that uses a glowing liquid to remain brightly lit in dim light
C	A frequency-determining unit for a transmitter or receiver
D	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It maintains a constant output voltage, regardless of variations in the input voltage
B	It stores one bit of data in either a 0 or 1 state
C	It produces a continuous square wave oscillating between 1 and 0
D	It switches momentarily to the opposite binary state and then returns to its original state after a set time

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

Select	Answer
A	Class AB
B	Push-pull
C	Class C
D	Push-push

32. - E7C06

What are the distinguishing features of an elliptical filter?

Select	Answer
A	Extremely flat response over its pass band with gradually rounded stop band corners
B	Gradual passband rolloff with minimal stop band ripple
C	Extremely sharp cutoff with one or more notches in the stop band
D	Gradual passband rolloff with extreme stop band ripple

33. - E7D05

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

Select	Answer
A	A constant current source
B	A shunt current source
C	A shunt regulator
D	A series regulator

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Phase comparator
B	Discriminator
C	Product detector
D	Phase detector

35. - E7F14

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

Select	Answer
A	Double-precision math routines
B	Higher data rate
C	More taps
D	Complex phasor representations

36. - E7G08

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

Select	Answer
A	It decreases linearly with increasing frequency
B	It does not vary with frequency
C	It increases linearly with increasing frequency
D	It decreases logarithmically with increasing frequency

37. - E7H13

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

Select	Answer
A	All of these choices are correct
B	Use a rubidium stabilized reference oscillator
C	Use a GPS signal reference
D	Use a temperature-controlled high Q dielectric resonator

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Sequential sampling
B	Harmonic regeneration
C	Phase reversal
D	Level shifting

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It increases as the RF carrier frequency increases
B	It does not depend on the RF carrier frequency
C	It decreases as the RF carrier frequency increases
D	It varies with the square root of the RF carrier frequency

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Reed-Solomon character encoding
B	Zero-sum character encoding
C	Use of trapezoidal data pulses
D	Use of sinusoidal data pulses

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	More difficult to copy
B	The generation of key clicks
C	The generation of RF harmonics
D	Limits data speed

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Yagi
B	Half-wave dipole
C	Quarter-wave vertical
D	Isotropic antenna

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	National Electrical Code
B	Next Element Comparison
C	Numeric Electrical Computation
D	Numerical Electromagnetic Code

44. - E9C15

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

Select	Answer
A	The horizontal beam width increases with height
B	The main lobe takeoff angle increases with increasing height
C	The main lobe takeoff angle decreases with increasing height
D	The horizontal beam width decreases with height

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Lower Q
B	Improved radiation efficiency
C	Higher losses
D	Greater structural strength

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A dielectric constant greater than 1
B	A reflection coefficient greater than 1
C	An SWR less than 1:1
D	An SWR greater than 1:1

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the output impedance of the generator
C	Very low impedance
D	Very high impedance

48. - E9G03

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

Select	Answer
A	Beam headings and radiation patterns
B	Trigonometric functions
C	Impedance and SWR values in transmission lines
D	Satellite azimuth and elevation bearings

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing either the number of wire turns in the loop or the area of the loop structure or both
B	By increasing the number of wire turns in the loop and reducing the area of the loop structure
C	By winding adjacent turns in opposing directions
D	By reducing the permeability of the loop shield

50. - E0A08

What does SAR measure?

Select	Answer
A	Synthetic Aperture Ratio of the human body
B	The rate of RF energy reflected from stationary terrain
C	Signal Amplification Rating
D	The rate at which RF energy is absorbed by the body

Figure E6-5