US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A01

What is the primary function of an external earth connection or ground rod?

Select	Answer
A	Lightning protection
B	Reduce RFI to telephones and home entertainment systems
C	Reduce RF current flow between pieces of equipment
D	Reduce received noise

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the highest frequency of the channel
B	At the center frequency of the channel
C	At the lowest frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

3. - E1B11

What does PRB-1 require of regulations affecting amateur radio?

Select	Answer
A	Reasonable accommodations of amateur radio must be made
B	Use of wireless devices in a vehicle is exempt from regulation
C	Amateur radio operations must be permitted in any private residence
D	No limitations may be placed on antenna size or placement

4. - E1C12

On what portion of the 630 meter band are phone emissions permitted?

Select	Answer
A	Only the top 3 kHz
B	The entire band
C	None
D	Only the bottom 3 kHz

5. - E1D09

Which UHF amateur bands have frequencies authorized for space stations?

Select	Answer
A	33 cm and 13 cm
B	70 cm and 13 cm
C	70 cm and 33 cm
D	70 cm only

6. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
B	They must collect and send the documents to the NCVEC for grading
C	They must collect and submit the documents to the coordinating VEC for grading
D	They must collect and send the documents to the FCC according to instructions

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

8. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The location of the ground control station
B	The polarization of uplink and downlink signals
C	The uplink and downlink frequency ranges
D	Power limits for uplink and downlink transmissions

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

Select	Answer
A	Transmitting on the abandoned TV channel 2
B	Using USB and demodulating the signal with a computer sound card
C	Transmitting on channels shared with cable TV
D	Using converted satellite TV dishes

10. - E2C10

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

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

11. - E2D01

Which of the following digital modes is designed for meteor scatter communications?

Select	Answer
A	Hellschreiber
B	WSPR
C	MSK144
D	APRS

12. - E2E13

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

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

13. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	1200 miles
B	10 miles to 50 miles
C	2500 miles
D	100 miles to 300 miles

14. - E3B04

What is meant by the terms "extraordinary" and "ordinary" waves?

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

15. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	UV emissions at 304 angstroms, correlated to the solar flux index
B	The ratio of x-ray flux to radio flux, correlated to sunspot number
C	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
D	The solar emission at 304 GHz, correlated to x-ray flare levels

16. - E4A04

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
B	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
C	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

17. - E4B04

Which S parameter represents input port return loss or reflection coefficient (equivalent to VSWR)?

Select	Answer
A	S21
B	S12
C	S11
D	S22

18. - E4C15

What is reciprocal mixing?

Select	Answer
A	Local oscillator phase noise mixing with adjacent strong signals to create interference to desired signals
B	Two digital signals combining from alternate time slots
C	Two out-of-band signals mixing to generate an in-band spurious signal
D	In-phase signals cancelling in a mixer resulting in loss of receiver sensitivity

19. - E4D02

Which of the following describes problems caused by poor dynamic range in a receiver?

Select	Answer
A	Oscillator instability and severe audio distortion of all but the strongest received signals
B	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
C	Spurious signals caused by cross-modulation and desensitization from strong adjacent signals
D	Cross-modulation of the desired signal and insufficient audio power to operate the speaker

20. - E4E06

What is one type of electrical interference that might be caused by 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

21. - E5A01

What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

Select	Answer
A	Conductance
B	Resonance
C	Capacitance
D	Resistance

22. - E5B03

How is impedance in polar form converted to an equivalent admittance?

Select	Answer
A	Square the magnitude and subtract 90 degrees from the angle
B	Take the square root of the magnitude and add 180 degrees to the angle
C	Take the reciprocal of the angle and change the sign of the magnitude
D	Take the reciprocal of the magnitude and change the sign of the angle

23. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By real and imaginary parts
B	By Y and G values
C	By phase angle and magnitude
D	By X and R values

24. - E5D04

Why are short connections used at microwave frequencies?

Select	Answer
A	To reduce phase shift along the connection
B	To increase neutralizing resistance
C	To increase compensating capacitance
D	To reduce noise figure

25. - E6A05

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	They are both high impedance
B	An FET has lower input impedance
C	An FET has higher input impedance
D	They are both low impedance

26. - E6B08

Which of the following is a Schottky barrier diode?

Select	Answer
A	Electrolytic rectifier
B	Thermionic emission diode
C	PIN junction
D	Metal-semiconductor junction

27. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Differential output capability
B	Immune to damage from static discharge
C	Lower distortion
D	Lower power consumption

28. - E6D01

Why should core saturation of an impedance matching transformer be avoided?

Select	Answer
A	Harmonics and distortion could result
B	RF susceptance would increase
C	Temporary changes of the core permeability could result
D	Magnetic flux would increase with frequency

29. - E6E12

Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?

Select	Answer
A	Epoxy coating is conductive above 300 MHz
B	Too many pins
C	Unsuitable for combining analog and digital signals
D	Excessive lead length

30. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	An LED and a phototransistor
B	An amplitude modulated helium-neon laser
C	A frequency modulated helium-neon laser
D	A lens and a photomultiplier

31. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic 0 at its output only when all inputs are logic 1
B	It produces logic 0 at its output only when all inputs are logic 0
C	It produces logic 0 at its output if some but not all inputs are logic 1
D	It produces logic 1 at its output only when all inputs are logic 1

32. - E7B11

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

Select	Answer
A	Self bias
B	Fixed bias
C	Output load resistor
D	Emitter bypass

33. - E7C09

What is a crystal lattice filter?

Select	Answer
A	A filter using lattice-shaped quartz crystals for high-Q performance
B	An audio filter made with four quartz crystals that resonate at 1 kHz intervals
C	A power supply filter made with interlaced quartz crystals
D	A filter with narrow bandwidth and steep skirts made using quartz crystals

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

Select	Answer
A	Minimum input voltage for rated power dissipation
B	Maximum that the output voltage may decrease at rated load
C	Maximum output voltage drops when the input voltage is varied over its specified range
D	Minimum input-to-output voltage required to maintain regulation

35. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the oscillator
B	A reactance modulator on the oscillator
C	A reactance modulator on the final amplifier
D	A balanced modulator on the audio amplifier

36. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

Select	Answer
A	Software is converted from source code to object code during operation of the receiver
B	A switching mixer is used to generate I and Q signals directly from the RF input
C	Incoming RF is converted to a control voltage for a voltage controlled oscillator
D	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal

37. - E7G01

What is the typical output impedance of an op-amp?

Select	Answer
A	Very high
B	100 ohms
C	Very low
D	1000 ohms

38. - 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 these choices are correct
B	Use a temperature-controlled high Q dielectric resonator
C	Use a rubidium stabilized reference oscillator
D	Use a GPS signal reference

39. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	Very high speed allows digitizing high frequencies
B	All these choices are correct
C	Immunity to out-of-sequence coding reduces spurious responses
D	Very low power consumption decreases frequency drift

40. - E8B09

What is deviation ratio?

Select	Answer
A	The ratio of the carrier center frequency to the audio modulating frequency
B	The ratio of the audio modulating frequency to the center carrier frequency
C	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
D	The ratio of the highest audio modulating frequency to the average audio modulating frequency

41. - E8C10

How may data rate be increased without increasing bandwidth?

Select	Answer
A	Using forward error correction
B	It is impossible
C	Increasing analog-to-digital conversion resolution
D	Using a more efficient digital code

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

Select	Answer
A	Repeat Request Rate (RRR)
B	Intermodulation Distortion (IMD)
C	Signal-to-noise ratio
D	Baud rate

43. - E9A13

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Apparent power
B	Effective radiated power
C	Half-power bandwidth
D	Power factor

44. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below 10 segments per half-wavelength?

Select	Answer
A	The antenna will become mechanically unstable
B	Ground conductivity will not be accurately modeled
C	The resulting design will favor radiation of harmonic energy
D	The computed feed point impedance may be incorrect

45. - E9C03

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

Select	Answer
A	A Figure-8 end-fire along the axis of the array
B	A Figure-8 broadside to the axis of the array
C	Cardioid
D	Omni-directional

46. - E9D07

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

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

47. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The gamma match
B	The delta match
C	The epsilon match
D	The stub match

48. - E9F04

What impedance does a 1/2-wavelength transmission line present to a generator when the line is shorted 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 high impedance
D	Very low impedance

49. - E9G03

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

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

50. - E9H05

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

Select	Answer
A	It has no clearly defined null
B	It has a bidirectional pattern
C	It is practical for use only on VHF and higher bands
D	All these choices are correct

Figure E7-1