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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	Yes, the DX station initiated the contact
B	No, one of the sidebands of the CW signal will be out of the band
C	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz
D	Yes, the displayed frequency is within the 80 meter CW band segment

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Only those club stations licensed to Amateur Extra class operators
B	Any FCC-licensed amateur station except a Technician class
C	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
D	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

3. - E1C04

What is meant by IARP?

Select	Answer
A	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
B	An indication of increased antenna reflected power
C	The internal amateur radio practices policy of the FCC
D	A forecast of intermittent aurora radio propagation

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	All except Technician Class
B	Any class with appropriate operator privileges
C	Only Amateur Extra Class
D	Only General, Advanced or Amateur Extra Class

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Destroy the application form
B	Maintain the application form with the VEC's records
C	Send the application form to the FCC and inform the FCC of the grade
D	Return the application document to the examinee

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and south of the U.S.-Canadian border
B	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
C	A line roughly parallel to and east of the U.S. Pacific coastline
D	A line roughly parallel to and west of the U.S. Atlantic coastline

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of the Doppler Effect
B	Because of ionospheric absorption
C	Because the satellite is spinning
D	Because of the satellite's low orbital altitude

8. - E2B07

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

Select	Answer
A	Luminance
B	Chroma
C	Hue
D	Spectral Intensity

9. - E2C11

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

Select	Answer
A	Send the call sign of the DX station three times, the words "this is", then your call sign three times
B	Send your full call sign once or twice
C	Send only the last two letters of your call sign until you make contact
D	Send your full call sign and grid square

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	300 baud packet
B	AMTOR
C	170 Hz shift, 45 baud RTTY
D	PSK31

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. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Mountain ranges
B	Forests
C	Bodies of water
D	Urban areas

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Independent waves created in the ionosphere that are elliptically polarized
B	Refracted rays and reflected waves
C	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
D	Long path and short path waves

14. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the Sun will cause disturbed conditions?

Select	Answer
A	Southward
B	Northward
C	Westward
D	Eastward

15. - E4A03

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

Select	Answer
A	A logic analyzer
B	A wattmeter
C	A time-domain reflectometer
D	A spectrum analyzer

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S22
B	S21
C	S12
D	S11

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The multiplex distortion stability
B	The minimum discernible signal
C	The maximum detectable spectrum
D	The meter display sensitivity

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
B	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
C	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
D	When the signals from the transmitters are reflected in phase from airplanes passing overhead

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By turning off the AC power line main circuit breaker and listening on a battery operated radio
B	By observing the AC power line waveform with an oscilloscope
C	By checking the power line voltage with a time domain reflectometer
D	By observing the AC power line voltage with a spectrum analyzer

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	315.6 Hz
B	23.67 kHz
C	157.8 Hz
D	47.3 kHz

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?

Select	Answer
A	14 degrees with the voltage lagging the current
B	76 degrees with the voltage lagging the current
C	76 degrees with the voltage leading the current
D	14 degrees with the voltage leading the current

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Venn diagram
B	Far field diagram
C	Phasor diagram
D	Near field diagram

23. - E5D03

What is microstrip?

Select	Answer
A	Miniature coax used for low power applications
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Lightweight transmission line made of common zip cord
D	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	3
B	6
C	2
D	1

25. - E6B06

Which of the following is a common use of a hot-carrier diode?

Select	Answer
A	As a variable capacitance in an automatic frequency control circuit
B	As a VHF/UHF mixer or detector
C	As balanced mixers in FM generation
D	As a constant voltage reference in a power supply

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	An algorithm for simulating logic functions during circuit design
B	A programmable collection of logic gates and circuits in a single integrated circuit
C	A device to control industrial equipment
D	Programmable equipment used for testing digital logic integrated circuits

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

Select	Answer
A	Ferrite toroids generally require fewer turns to produce a given inductance value
B	Ferrite toroids are easier to use with surface mount technology
C	Ferrite toroids generally have lower initial permeability
D	Ferrite toroids generally have better temperature stability

28. - E6E03

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

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

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 modern replacement for a quartz crystal oscillator which displays its fundamental frequency
C	A display that uses a glowing liquid to remain brightly lit in dim light
D	A frequency-determining unit for a transmitter or receiver

30. - E7A11

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

Select	Answer
A	Negative logic
B	Assertive Logic
C	Reverse Logic
D	Positive Logic

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Voltage regulation
B	Fixed bias
C	Collector load
D	Emitter load

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The gain of the RF stage preceding the filter
B	The DC voltage applied to the quartz crystal
C	The relative frequencies of the individual crystals
D	The amplitude of the signals passing through the filter

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A tunnel diode
B	A Zener diode
C	An SCR
D	A varactor diode

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Automatic limiting occurs
B	Mixer blanking occurs
C	A beat frequency is generated
D	Spurious mixer products are generated

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters can respond faster to impulses
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	FIR filters delay all frequency components of the signal by the same amount
D	All of these choices are correct

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	94
B	0.21
C	24
D	47

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Bias the crystal at a specified voltage
B	Provide the crystal with a specified parallel inductance
C	Bias the crystal at a specified current
D	Provide the crystal with a specified parallel capacitance

38. - E8A13

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

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

39. - E8B02

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

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

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 104 Hz
B	Approximately 26 Hz
C	Approximately 52 Hz
D	Approximately 13 Hz

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to change frequencies
B	The receiver is always equipped with a digital blanker
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	9.85 dB
B	14.15 dB
C	6.17 dB
D	12.5 dB

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	Feed point impedance may become negative
B	The gain may change depending on frequency
C	The E-field and H-field patterns may reverse
D	Element spacing limits could be exceeded

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A type of ground-plane antenna
B	A dipole consisting of one wavelength of wire forming a very thin loop
C	A dipole one-quarter wavelength long
D	A dipole configured to provide forward gain

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?

Select	Answer
A	The radiation resistance increases and the capacitive reactance decreases
B	The radiation resistance decreases and the capacitive reactance decreases
C	The radiation resistance increases and the capacitive reactance increases
D	The radiation resistance decreases and the capacitive reactance increases

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Use the universal stub matching technique
B	Connect a series-resonant LC network across the antenna feed terminals
C	Use a 50 ohm 1:1 balun between the antenna and feed line
D	Connect a parallel-resonant LC network across the antenna feed terminals

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The line length
B	The termination impedance
C	Dielectric materials used in the line
D	The center conductor resistivity

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Impedance along transmission lines
B	Antenna radiation pattern
C	Radio propagation
D	Radiation resistance

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It has a bidirectional pattern
B	It receives equally well in all directions
C	It is non-rotatable
D	It is practical for use only on VHF bands

50. - E0A08

What does SAR measure?

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

Figure E6-2

Figure E7-2

Figure E7-4