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. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

Select	Answer
A	3 to 30 MHz
B	300 to 3000 MHz
C	300 kHz to 3 MHz
D	30 to 300 MHz

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

3. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must obtain a construction permit from the airport zoning authority
B	You must file an Environmental Impact Statement with the EPA before construction begins
C	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
D	You must submit engineering drawings to the FAA

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

Select	Answer
A	Operators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station
B	An environmental impact statement must be filed with the Department of the Interior
C	A special endorsement must be requested from the FCC
D	Operators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

Select	Answer
A	A message forwarding station or automatically controlled digital station
B	A space station, beacon station, or telecommand station
C	A local repeater or linked repeater station
D	All these choices are correct

6. - E1E12

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

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

7. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	The equipment dealer assembled it from a kit
D	It was imported from a manufacturer in another country and was certificated by that country's government

8. - E2A03

How is the signal inverted by an inverting linear transponder?

Select	Answer
A	The signal is reduced to I and Q components and the Q component is filtered out
B	The signal is passed through a non-linear filter
C	The signal is passed through a mixer and the difference rather than the sum is transmitted
D	The signal is detected and remodulated on the reverse sideband

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. - E2C10

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

Select	Answer
A	All these choices are correct
B	To separate the calling stations from the DX station
C	Because the DX station may be transmitting on a frequency that is prohibited to some responding stations
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	MSK144
B	Hellschreiber
C	APRS
D	WSPR

12. - E2E05

Which of these digital modes does not support keyboard-to-keyboard operation?

Select	Answer
A	RTTY
B	PACTOR
C	MFSK
D	PSK31

13. - E3A04

What do Hepburn maps predict?

Select	Answer
A	Sporadic E propagation
B	Locations of auroral reflecting zones
C	Probability of tropospheric propagation
D	Likelihood of rain scatter along cold or warm fronts

14. - E3B04

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

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

15. - E3C11

What does VOACAP software model?

Select	Answer
A	HF propagation
B	AC current and impedance
C	VHF radio propagation
D	AC voltage and impedance

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and frequency
B	SWR and time
C	SWR and frequency
D	RF amplitude and time

17. - E4B08

Which of the following can be used to measure the Q of a series-tuned circuit?

Select	Answer
A	The resonant frequency of the circuit
B	The bandwidth of the circuit's frequency response
C	The inductance to capacitance ratio
D	The frequency shift

18. - E4C15

What is reciprocal mixing?

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

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	Adjacent channel interference
D	Intermodulation

20. - E4E09

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

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

21. - E5A16

What is the resonant frequency of an RLC circuit if R is 33 ohms, L is 50 microhenries and C is 10 picofarads?

Select	Answer
A	23.5 MHz
B	23.5 kHz
C	7.12 MHz
D	7.12 kHz

22. - 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 leading 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 lagging the current

23. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

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

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. - E6A09

What is a depletion-mode FET?

Select	Answer
A	An FET that has no current flow between source and drain when no gate voltage is applied
B	Any FET for which holes are the majority carriers
C	An FET that exhibits a current flow between source and drain when no gate voltage is applied
D	Any FET without a channel

26. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Insufficient forward voltage
B	Excessive inverse voltage
C	Excessive junction temperature
D	Charge carrier depletion

27. - E6C11

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

Select	Answer
A	2
B	5
C	6
D	4

28. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores exhibit greater hysteresis
B	Toroidal cores make it easier to couple the magnetic energy into other components
C	Toroidal cores have lower Q characteristics
D	Toroidal cores confine most of the magnetic field within the core material

29. - E6E01

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

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

30. - E6F07

What is a solid-state relay?

Select	Answer
A	A mechanical relay that latches in the on or off state each time it is pulsed
B	A relay using transistors to drive the relay coil
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A semiconductor passive delay line

31. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It produces a continuous square wave oscillating between 1 and 0
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It stores one bit of data in either a 0 or 1 state
D	It maintains a constant output voltage, regardless of variations in the input voltage

32. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	Low input impedance
B	High power gain
C	Low bandwidth
D	High filament voltage

33. - E7C07

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

Select	Answer
A	A matching network in which all components are isolated from ground
B	A Phase Inverter Load network
C	A network with only three discrete parts
D	A Pi-network with an additional series inductor on the output

34. - E7D13

What is the equation for calculating power dissipated by a series linear voltage regulator?

Select	Answer
A	Input voltage multiplied by input current
B	Input voltage divided by output current
C	Output voltage multiplied by output current
D	Voltage difference from input to output multiplied by output current

35. - E7E03

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	A circuit for detecting FM signals
B	An automatic band-switching circuit
C	An FM generator circuit
D	A circuit for filtering two closely adjacent signals

36. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	A Hilbert-transform filter
B	An adaptive filter
C	A notch filter
D	An elliptical filter

37. - E7G04

What is meant by the "op-amp input offset voltage"?

Select	Answer
A	The potential between the amplifier input terminals of the op-amp in an open loop condition
B	The output voltage of the op-amp minus its input voltage
C	The differential input voltage needed to bring the open loop output voltage to zero
D	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage

38. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A hybrid synthesizer
B	A diode-switching matrix synthesizer
C	A direct digital synthesizer
D	A phase-locked loop synthesizer

39. - E8A11

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

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

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	1.67
B	0.167
C	0.6
D	60

41. - E8C05

What is the approximate bandwidth of a 13-WPM International Morse Code transmission?

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

42. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Increase keying waveform rise and fall times
B	High-pass filters at the transmitter output
C	Low-pass filters at the transmitter output
D	Reduce keying waveform rise and fall times

43. - E9A04

Which of the following factors affect the feed point impedance of an antenna?

Select	Answer
A	The input power level
B	Antenna height
C	The settings of an antenna tuner at the transmitter
D	Transmission line length

44. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from a theoretical isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio
B	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
C	They are the same
D	The total amount of radiation from the directional antenna is increased by the gain of the antenna

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

46. - E9D07

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

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

47. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To cancel the inductive reactance of the matching network
C	To provide DC isolation between the feed line and the antenna
D	To transform the antenna impedance to a higher value

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

Select	Answer
A	7.0 meters
B	8.5 meters
C	10.6 meters
D	13.3 meters

49. - E9G05

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

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

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	They must be erected at least 1/2 wavelength above the ground to attain good directivity
B	Low loss coax transmission line is essential for good performance
C	Atmospheric noise is so high that gain over a dipole is not important
D	All these choices are correct

Figure E6-3