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

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

1. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	E field and H field radiation intensity peaks can occur at different locations
B	Ground reflections and scattering make the field strength vary with location
C	All these choices are correct
D	The body reacts to electromagnetic radiation from both the E and H fields

2. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	1 kHz above the lower band edge
B	300 Hz above the lower band edge
C	3 kHz above the lower band edge
D	The exact lower band edge

3. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Florida surrounding Cape Canaveral
B	An area in New Mexico surrounding the White Sands Test Area
C	An area surrounding the National Radio Astronomy Observatory
D	An area in Puerto Rico surrounding the Arecibo Radio Telescope

4. - E1C12

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

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

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

Select	Answer
A	5 watts
B	100 watts
C	1 watt
D	2 watts

6. - E1E03

What is a Volunteer Examiner Coordinator?

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

7. - 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	420 MHz - 430 MHz
B	222 MHz - 223 MHz
C	440 MHz - 450 MHz
D	53 MHz - 54 MHz

8. - E2A13

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Multi-satellite relaying
B	Node hopping
C	Store-and-forward
D	Digipeating

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To lock the color burst oscillator in color SSTV images
B	To provide vertical synchronization
C	To identify the SSTV mode being used
D	To identify the call sign of the station transmitting

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	No additional indicator is required
C	/ followed by the ARRL Section of the remote station
D	/R# where # is the district of the remote station

11. - E2D09

What type of modulation is used for JT65 contacts?

Select	Answer
A	PSK
B	RTTY
C	Multi-tone AFSK
D	IEEE 802.11

12. - E2E06

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

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

13. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	The jet stream
B	Temperature inversion
C	Dust devil
D	Wind shear

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only around sunset
B	Only in hours of darkness
C	Only around sunset and sunrise
D	Any time

15. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	An increase in the critical frequency
B	Increasing disruption of the geomagnetic field
C	Higher levels of solar UV radiation
D	Decreasing disruption of the geomagnetic field

16. - E4A11

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

17. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	25 watts
B	75 watts
C	100 watts
D	125 watts

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

Select	Answer
A	A properly adjusted product detector
B	A notch filter
C	A narrow IF filter
D	A front-end filter or pre-selector

19. - E4D11

Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

Select	Answer
A	Odd-order products overload the IF filters
B	Odd-order products of two signals in the band of interest are also likely to be within the band
C	Odd-order products are an indication of poor image rejection
D	Odd-order intermodulation produces three products for every input signal within the band of interest

20. - E4E07

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Common-mode currents on the shield and conductors
B	Low inductance ground connections at both ends of the shield
C	Use of braided shielding material
D	Tying all ground connections to a common point resulting in differential-mode currents in the shield

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	L/R
B	R/L
C	Minimum
D	Maximum

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

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

23. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A negative magnitude
B	A negative phase angle
C	A positive phase angle
D	A positive magnitude

24. - E5D03

What is microstrip?

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

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

Select	Answer
A	In very low-frequency RF circuits
B	In high-current rectifier circuits
C	In high-power audio circuits
D	In microwave circuits

26. - E6B09

What is a common use for point-contact diodes?

Select	Answer
A	As a constant current source
B	As a high-voltage rectifier
C	As an RF detector
D	As a constant voltage source

27. - E6C11

In Figure E6-3, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	5
B	6
C	2
D	4

28. - E6D06

What core material property determines the inductance of an inductor?

Select	Answer
A	Thermal impedance
B	Resistance
C	Reactivity
D	Permeability

29. - E6E01

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

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

30. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device for generating RTTY signals by means of a rotating light source
B	A digital encryption device often used to encrypt spacecraft control signals
C	A device that detects rotation of a control by interrupting a light source with a patterned wheel
D	A device that measures the strength of a beam of light using analog to digital conversion

31. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic 1 at its output if any or all inputs are logic 1
B	It produces logic 0 at its output if all inputs are logic 1
C	It only produces logic 0 at its output when all inputs are logic 1
D	It produces logic 1 at its output if all inputs are logic 0

32. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Linear amplifiers have high gain resulting in higher harmonic content
B	Switching amplifiers use push-pull circuits
C	The power transistor is at saturation or cutoff most of the time
D	Switching amplifiers operate at higher voltages

33. - E7C09

What is a crystal lattice filter?

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

34. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-2?

Select	Answer
A	It provides negative feedback to improve regulation
B	It controls the current supplied to the load
C	It provides a constant load for the voltage source
D	It provides D1 with current

35. - E7E09

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

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

36. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At four times the rate of the highest frequency component of the signal
B	At least twice the rate of the highest frequency component of the signal
C	At least half the rate of the highest frequency component of the signal
D	At the same rate as the highest frequency component of the signal

37. - E7G05

How can unwanted ringing and audio instability be prevented in an op-amp RC audio filter circuit?

Select	Answer
A	Restrict Q but increase gain
B	Restrict both gain and Q
C	Restrict gain but increase Q
D	Increase both gain and Q

38. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Armstrong and deForest
B	Negative feedback and balanced feedback
C	Colpitts and Hartley
D	Pierce and Zener

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

Select	Answer
A	Level shifting
B	Successive approximation
C	Phase reversal
D	Harmonic regeneration

40. - E8B01

What is the modulation index of an FM signal?

Select	Answer
A	The ratio of modulating signal amplitude to frequency deviation
B	The type of modulation used by the transmitter
C	The ratio of frequency deviation to modulating signal frequency
D	The bandwidth of the transmitted signal divided by the modulating signal frequency

41. - E8C07

What is the bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	15.36 kHz
B	5.76 kHz
C	9.6 kHz
D	4.8 kHz

42. - E8D08

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

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

43. - E9A13

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

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

44. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	14 dB
B	24 dB
C	36 dB
D	18 dB

45. - E9C13

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

Select	Answer
A	The horizontal beamwidth decreases
B	The takeoff angle of the lowest elevation lobe decreases
C	The horizontal beamwidth increases
D	The takeoff angle of the lowest elevation lobe increases

46. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To minimize losses
B	To swamp out harmonics
C	To lower the radiation angle
D	To minimize the Q

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

Select	Answer
A	50 ohms
B	450 ohms
C	62 ohms
D	75 ohms

48. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Lower loss
B	Lower velocity factor
C	Smaller reflection coefficient
D	Higher SWR

49. - E9G05

Which of the following is a common use for a Smith chart?

Select	Answer
A	Determine the impedance of a transmission line, given the physical dimensions
B	Determine the length and position of an impedance matching stub
C	Determine the gain of an antenna given the physical and electrical parameters
D	Determine the loss/100 feet of a transmission line, given the velocity factor and conductor materials

50. - 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 provides diversity reception that cancels multipath signals
D	It modifies the pattern of a DF antenna array to provide a null in one direction

Figure E6-3

Figure E7-2

Figure E9-1