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

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

2. - 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?

Select	Answer
A	The amateur station must cease operation
B	The amateur station must cease operation on all frequencies above 30 MHz
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	The use of devices and procedures for control so that the control operator does not have to be present at a control point
B	A station operating with its output power controlled automatically
C	Remotely controlling a station's antenna pattern through a directional control link
D	The use of a control link between a control point and a locally controlled station

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
B	A radio communications service using stations on Earth satellites for public service broadcast
C	A radio communications service using amateur radio stations on satellites
D	A spacecraft launching service for amateur-built satellites

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	All these choices are correct
B	Photocopy all examination documents and forward them to the FCC for processing
C	Issue the examinee the new or upgrade license
D	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	None, they must obtain a U.S. license
B	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
C	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
D	All privileges of the Extra Class license

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Doppler shift of beacon signals
B	APRS
C	Bandwidth compressed LORAN
D	Radar

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	20 KHz
B	10 KHz
C	3 KHz
D	15 KHz

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Select	Answer
A	Switch to a higher frequency HF band
B	Wait 90 minutes or so for the signal degradation to pass
C	Wait 24 hours before attempting another communication on the band
D	Switch to a lower frequency HF band

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	All of these choices are correct
B	It supplies signals to guide the antenna to track the Moon
C	It controls the receiver to track Doppler shift
D	It can decode signals many dB below the noise floor using FEC

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	Another station you are unable to hear is using the frequency
B	All of these choices are correct
C	The protocol version you are using is not the supported by the digital station
D	Your transmit frequency is incorrect

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is at apogee
B	When the MUF is above 30 MHz
C	When the Moon is at perigee
D	When the Moon is full

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

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

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Elliptical
B	Circular
C	Vertical
D	Horizontal

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 spectrum analyzer
C	A wattmeter
D	A time-domain reflectometer

16. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Frequency order of the measurements
B	The relative time between measurements
C	Relative quality of the data
D	The port or ports at which measurements are made

17. - E4C17

Which of the following has the largest effect on an SDR receiver's linearity?

Select	Answer
A	RAM speed used for data storage
B	CPU register width in bits
C	Analog-to-digital converter sample width in bits
D	Anti-aliasing input filter bandwidth

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A band-pass filter in the feed line between the transmitter and receiver
B	A Class C final amplifier
C	A properly terminated circulator at the output of the transmitter
D	A Class D final amplifier

19. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A whining type noise that continually pulses off and on
B	A loud AC hum in the audio output of your station receiver
C	The appearance of unstable modulated or unmodulated signals at specific frequencies
D	A clicking noise at intervals of a few seconds

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	47.3 kHz
C	23.67 kHz
D	157.8 Hz

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	A discharge factor of one
B	One discharge period
C	An exponential discharge rate of one
D	One time constant

22. - E5C01

Which of the following represents a capacitive reactance in rectangular notation?

Select	Answer
A	X
B	Omega
C	-jX
D	+jX

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.414
B	1.73
C	0.866
D	0.5

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	Superconductor-type
B	N-type
C	P-type
D	Bipolar-type

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	A constant current drop under conditions of varying voltage
B	A constant voltage drop under conditions of varying current
C	A negative resistance region
D	An internal capacitance that varies with the applied voltage

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A logic device with two CMOS circuits per package
B	A FET logic family based on bimetallic semiconductors
C	An integrated circuit logic family using both bipolar and CMOS transistors
D	A logic family based on bismuth CMOS devices

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Ferrite
B	Powdered-iron
C	Ceramic
D	Brass

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	450 ohms
B	10 ohms
C	50 ohms
D	300 ohms

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	12 V
C	1.5 V
D	0.5 V

30. - E7A10

What is a truth table?

Select	Answer
A	A diagram showing logic states when the digital device output is true
B	A table of logic symbols that indicate the high logic states of an op-amp
C	A list of inputs and corresponding outputs for a digital device
D	A table of logic symbols that indicate the logic states of an op-amp

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A low-pass filter to remove switching signal components
B	A high-pass filter to compensate for low gain at low frequencies
C	A matched load resistor to prevent damage by switching transients
D	A temperature compensating load resistor to improve linearity

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

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	The controlled device's duty cycle is changed to produce a constant average output voltage
B	The resistance of a control element is varied in direct proportion to the line voltage or load current
C	It is generally less efficient than a linear regulator
D	It gives a ramp voltage at its output

34. - E7E06

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

Select	Answer
A	To remove third-order distortion products
B	For compatibility with transmitters using phase modulation
C	To reduce impulse noise reception
D	For higher efficiency

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

Select	Answer
A	Inactive and Quiescent
B	Instantaneous and Quasi-stable
C	In-phase and Quadrature
D	Instantaneous and Quenched

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	24
B	94
C	0.21
D	47

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Colpitts, Hartley and Pierce
B	Taft, Hartley and Pierce
C	Pierce, Fenner and Beane
D	Taft, Pierce and negative feedback

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Fourier analysis
B	Differential analysis
C	Numerical analysis
D	Vector analysis

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	Two or more information streams are merged into a baseband, which then modulates the transmitter
B	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
C	The transmitted signal jumps from band to band at a predetermined rate
D	The transmitted signal is divided into packets of information

40. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, redundant data is substituted
B	Special binary codes provide automatic correction
C	Special polynomial codes provide automatic correction
D	If errors are detected, a retransmission is requested

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	-30 dB
B	+10 dB
C	+15 dB
D	-20 dB

42. - E9A02

What antenna has no gain in any direction?

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

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	3 dB
B	28 dB
C	15 dB
D	24 dB

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The low-angle radiation decreases
B	The low-angle radiation increases
C	The high-angle radiation increases
D	Both the high-angle and low-angle radiation decrease

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain does not change
B	Gain increases by 3 dB
C	Gain increases by 6 dB
D	Gain is multiplied by 0.707

46. - E9E12

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

Select	Answer
A	It makes sure the antenna has a low-angle radiation pattern
B	It ensures that each driven element operates in concert with the others to create the desired antenna pattern
C	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
D	It allows single-band antennas to operate on other bands

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	A capacitive reactance
B	The same as the input impedance to the final generator stage
C	The same as the characteristic impedance of the line
D	An inductive reactance

48. - E9G03

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

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

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It allows DF antennas to receive signals at different vertical angles
B	It increases the sensitivity of a DF antenna array
C	It modifies the pattern of a DF antenna array to provide a null in one direction
D	It provides diversity reception that cancels multipath signals

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only the most powerful transmitter
B	Only commercial transmitters
C	Each transmitter operating with a duty-cycle greater than 50 percent
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E7-4

Figure E9-2