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

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1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave bands?

Select	Answer
A	Microwaves often travel long distances by ionospheric reflection
B	The high gain antennas commonly used can result in high exposure levels
C	Microwaves are ionizing radiation
D	The extremely high frequency energy can damage the joints of antenna structures

2. - E1A01

Which of the following carrier frequencies is illegal for LSB AFSK emissions on the 17 meter band RTTY and data segment of 18.068 to 18.110 MHz?

Select	Answer
A	18.068 MHz
B	18.100 MHz
C	18.107 MHz
D	18.110 MHz

3. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	Military Auxiliary Radio System (MARS) channels
B	Specific local government channels
C	Specific segments in the amateur service MF, HF, VHF and UHF bands
D	All amateur service frequencies authorized to the control operator

4. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	3 minutes
B	30 seconds
C	5 minutes
D	10 minutes

5. - E1D10

Which amateur stations are eligible to be telecommand stations of space stations (subject to the privileges of the class of operator license held by the control operator of the station)?

Select	Answer
A	Any amateur station so designated by the ITU
B	All these choices are correct
C	Any amateur station so designated by the space station licensee
D	Any amateur station designated by NASA

6. - E1E03

What is a Volunteer Examiner Coordinator?

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

7. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 420 MHz
B	Only on amateur frequencies above 50 MHz
C	Only on amateur frequencies above 144 MHz
D	Only on amateur frequencies above 222 MHz

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

Select	Answer
A	The 23 centimeter and 13 centimeter bands
B	Which sideband to use
C	The 2 meter and 70 centimeter bands
D	FM and Digital Store-and-Forward systems

9. - E2B12

What signals SSTV receiving software to begin a new picture line?

Select	Answer
A	Specific tone frequencies
B	A two-tone signal
C	Specific tone amplitudes
D	Elapsed time

10. - E2C01

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control and the remote transmitter is located in the U.S.?

Select	Answer
A	/ followed by the USPS two-letter abbreviation for the state in which the remote station is located
B	/ followed by the ARRL Section of the remote station
C	/R# where # is the district of the remote station
D	No additional indicator is required

11. - E2D05

What is one advantage of the JT65 mode?

Select	Answer
A	Permits fast-scan TV transmissions over narrow bandwidth
B	Uses only a 65 Hz bandwidth
C	The ability to decode signals which have a very low signal-to-noise ratio
D	Easily copied by ear if necessary

12. - E2E12

How do ALE stations establish contact?

Select	Answer
A	ALE radios activate when they hear their signal echoed by back scatter
B	ALE radios monitor an internet site for the frequency they are being paged on
C	ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
D	ALE radios send a constant tone code to establish a frequency for future use

13. - 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 perigee
B	When the moon is full
C	When the moon is at apogee
D	When the MUF is above 30 MHz

14. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
B	Propagation between points located on the magnetic equator
C	Propagation between points at the same latitude
D	Propagation between a point on the equator and its antipodal point

15. - E3C15

What might be indicated by a sudden rise in radio background noise across a large portion of the HF spectrum?

Select	Answer
A	Increased transequatorial propagation is likely
B	A temperature inversion has occurred
C	Long-path propagation is likely
D	A solar flare has occurred

16. - E4A11

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

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

17. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Decade divider accuracy
B	Input attenuator accuracy
C	Temperature coefficient of the logic
D	Time base accuracy

18. - E4C07

What does the MDS of a receiver represent?

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

19. - E4D06

What is the term for spurious signals generated by the combination of two or more signals in a non-linear device or circuit?

Select	Answer
A	Neutralization
B	Amplifier desensitization
C	Intermodulation
D	Adjacent channel interference

20. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	FM signals can no longer be demodulated
B	Nearby signals may appear to be excessively wide even if they meet emission standards
C	The audio frequency bandwidth of the received signal might be compressed
D	Received audio in the speech range might have an echo effect

21. - E5A11

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

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

22. - E5B10

What is the relationship between the AC current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage leads current by 90 degrees
B	Voltage and current are in phase
C	Current leads voltage by 90 degrees
D	Voltage and current are 180 degrees out of phase

23. - E5C04

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Maidenhead grid
B	Faraday grid
C	Elliptical coordinates
D	Rectangular coordinates

24. - E5D04

Why are short connections used at microwave frequencies?

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

25. - E6A11

In Figure E6-1, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	3
B	2
C	1
D	6

26. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Forward DC bias current
B	Reverse voltage larger than the RF signal
C	A sub-harmonic pump signal
D	Capacitance of an RF coupling capacitor

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	1
B	4
C	3
D	2

28. - E6D08

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

Select	Answer
A	Powdered-iron cores generally require fewer turns to produce a given inductance
B	Powdered-iron cores generally maintain their characteristics at higher currents
C	Powdered-iron cores use smaller diameter wire for the same inductance
D	Powdered-iron cores generally have greater initial permeability

29. - E6E01

Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?

Select	Answer
A	Lower transconductance
B	Lower junction voltage drop
C	Higher noise figures
D	Higher electron mobility

30. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The relative fraction of light that is converted to current
B	The output RF power divided by the input DC power
C	Cost per kilowatt-hour generated
D	The open-circuit voltage divided by the short-circuit current under full illumination

31. - E7A11

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

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

32. - E7B04

Where on the load line of a Class A common emitter amplifier would bias normally be set?

Select	Answer
A	Where the load line intersects the voltage axis
B	Approximately halfway between saturation and cutoff
C	At a point where the bias resistor equals the load resistor
D	At a point where the load line intersects the zero bias current curve

33. - E7C11

Which of the following describes a receiving filter's ability to reject signals occupying an adjacent channel?

Select	Answer
A	Passband ripple
B	Phase response
C	Shape factor
D	Noise factor

34. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

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

35. - E7E09

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

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

36. - E7F12

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

37. - E7G02

What is ringing in a filter?

Select	Answer
A	Undesired oscillations added to the desired signal
B	Partial cancellation of the signal over a range of frequencies
C	A reduction in high frequency response
D	An echo caused by a long time delay

38. - E7H03

How is positive feedback supplied in a Hartley oscillator?

Select	Answer
A	Through a tapped coil
B	Through a neutralizing capacitor
C	Through a capacitive divider
D	Through link coupling

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

Select	Answer
A	Peak envelope power
B	Power factor
C	Reciprocal mixing
D	Total harmonic distortion

40. - E8B05

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus-or-minus 5 kHz when the maximum modulation frequency is 3 kHz?

Select	Answer
A	0.6
B	60
C	0.167
D	1.67

41. - E8C03

Why should phase-shifting of a PSK signal be done at the zero crossing of the RF signal?

Select	Answer
A	All these choices are correct
B	To improve carrier suppression
C	To minimize bandwidth
D	To simplify modulation

42. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
B	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
C	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
D	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

43. - E9A12

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 6 dB gain over an isotropic antenna?

Select	Answer
A	3.85 dB
B	8.15 dB
C	6.0 dB
D	2.79 dB

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Graphical analysis
B	Mutual impedance analysis
C	Method of Moments
D	Calculus differentiation with respect to physical properties

45. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The lobes become more perpendicular to the wire
B	The front-to-back ratio decreases
C	The vertical angle increases
D	The lobes align more in the direction of the wire

46. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To lower the losses
B	To lower the Q
C	To increase the SWR bandwidth
D	To cancel capacitive reactance

47. - E9E07

What parameter describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Dielectric constant
B	Reflection coefficient
C	Characteristic impedance
D	Velocity factor

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

49. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Radiation-pattern circles
B	Standing wave ratio circles
C	Coaxial-length circles
D	Antenna-length circles

50. - E9H09

What is a Pennant antenna?

Select	Answer
A	A small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms
B	A stealth antenna built to look like a flagpole
C	A four-element, high-gain vertical array invented by George Pennant
D	A form of rhombic antenna terminated in a variable capacitor to provide frequency diversity

Figure E6-1

Figure E6-3