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 received noise
C	Reduce RFI to telephones and home entertainment systems
D	Reduce RF current flow between pieces of equipment

2. - E1A04

With your transceiver displaying the carrier frequency of phone signals, you hear a DX station calling CQ on 3.601 MHz LSB. Is it legal to return the call using lower sideband on the same frequency?

Select	Answer
A	Yes, because the DX station initiated the contact
B	No, U.S. stations are not permitted to use phone emissions below 3.610 MHz
C	Yes, because the displayed frequency is within the 75 meter phone band segment
D	No, the sideband will extend beyond the edge of the phone band segment

3. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	A signal transmitted to prevent its detection by any station other than the intended recipient
B	An amateur station transmission made without the proper call sign identification
C	An emission outside the signal's necessary bandwidth that can be reduced or eliminated without affecting the information transmitted
D	Any transmitted signal that unintentionally interferes with another licensed radio station

4. - E1C04

What is meant by IARP?

Select	Answer
A	The internal amateur radio practices policy of the FCC
B	An indication of increased antenna reflected power
C	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
D	A forecast of intermittent aurora radio propagation

5. - E1D04

Which of the following is required in the identification transmissions from a balloon-borne telemetry station?

Select	Answer
A	The output power of the balloon transmitter
B	All these choices are correct
C	Call sign
D	The station's six-character Maidenhead grid locator

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

7. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

8. - E2A06

What are Keplerian elements?

Select	Answer
A	High-emission heater filaments used in magnetron tubes
B	Parameters that define the orbit of a satellite
C	Phase reversing elements in a Yagi antenna
D	Encrypting codes used for spread spectrum modulation

9. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Luminance
B	Chroma
C	Hue
D	Spectral intensity

10. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send the call sign of the DX station three times, the words this is,then your call sign three times
B	Send your full call sign and grid square
C	Send only the last two letters of your call sign until you make contact
D	Send your full call sign once or twice

11. - E2D04

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

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

12. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK applies the data signal to the transmitter VFO, while AFSK transmits tones via phone
B	Direct FSK can transmit faster baud rates
C	Only direct FSK can be decoded by computer
D	Direct FSK occupies less bandwidth

13. - E3A05

Tropospheric propagation of microwave signals often occurs in association with what phenomenon?

Select	Answer
A	Lightning discharges
B	Grayline
C	Sprites and jets
D	Warm and cold fronts

14. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	6 meters to 2 meters
B	160 meters to 10 meters
C	Only 30 meters to 10 meters
D	Only 160 meters to 40 meters

15. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Transequatorial
B	Polar
C	Sporadic E
D	NVIS

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Logic analyzer
C	Bit error rate tester
D	Modulation monitor

17. - E4B04

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

Select	Answer
A	S12
B	S22
C	S11
D	S21

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

Select	Answer
A	Receiver power consumption can be reduced when wider bandwidth is not required
B	The noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
C	Multiple frequencies can be received simultaneously if desired
D	Receive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference

19. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	173.35 MHz and 139.40 MHz
B	146.34 MHz and 146.61 MHz
C	146.88 MHz and 146.34 MHz
D	146.10 MHz and 147.30 MHz

20. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals that appear across a wide bandwidth
B	Signals that have a sharply peaked frequency distribution
C	Signals that are constant at all IF levels
D	Signals that appear at one IF but not another

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

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

22. - E5B03

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

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

23. - E5C11

Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 7
B	Point 1
C	Point 3
D	Point 8

24. - E5D07

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	1.42 mW
B	355 W
C	252 W
D	704 W

25. - E6A07

Which of the following indicates that a silicon NPN junction transistor is biased on?

Select	Answer
A	Base-to-emitter voltage of approximately 0.6 to 0.7 volts
B	Base-to-emitter resistance of approximately 6 to 7 ohms
C	Base-to-emitter resistance of approximately 0.6 to 0.7 ohms
D	Base-to-emitter voltage of approximately 6 to 7 volts

26. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Zener diode
B	Tunnel diode
C	Silicon-controlled rectifier
D	Varactor diode

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	It has the high input impedance of CMOS and the low output impedance of bipolar transistors
B	All these choices are correct
C	It is immune to electrostatic damage
D	Its simplicity results in much less expensive devices than standard CMOS

28. - E6D07

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Magnetizing current
B	Stabilizing current
C	Excitation current
D	Direct current

29. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Radial lead
B	Surface mount
C	Axial lead
D	TO-220

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 semiconductor passive delay line
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A relay using transistors to drive the relay coil

31. - E7A01

Which circuit is bistable?

Select	Answer
A	An AND gate
B	A bipolar amplifier
C	A flip-flop
D	An OR gate

32. - E7B13

Which of the following describes an emitter follower (or common collector) amplifier?

Select	Answer
A	A two-transistor amplifier with the emitters sharing a common bias resistor
B	An OR circuit with only one emitter used for output
C	A differential amplifier with both inputs fed to the emitter of the input transistor
D	An amplifier with a low impedance output that follows the base input voltage

33. - E7C11

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

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

34. - E7D02

What is a characteristic of a switching electronic voltage regulator?

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

35. - E7E09

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

Select	Answer
A	Spurious mixer products are generated
B	Automatic limiting occurs
C	Mixer blanking occurs
D	A beat frequency is 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 least twice the rate of the highest frequency component of the signal
B	At the same rate as the highest frequency component of the signal
C	At least half the rate of the highest frequency component of the signal
D	At four times the rate of the highest frequency component of the signal

37. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It increases linearly with increasing frequency
B	It decreases linearly with increasing frequency
C	It decreases logarithmically with increasing frequency
D	It does not vary with frequency

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

39. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all its harmonics?

Select	Answer
A	A square wave
B	A cosine wave
C	A sawtooth wave
D	A sine wave

40. - E8B10

What is frequency division multiplexing?

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

41. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The rate at which the waveform changes to convey information
B	The number of characters carried per second by the station-to-station link
C	The duration of each bit in a message sent over the air
D	The number of control characters in a message packet

42. - E8D02

What spread spectrum communications technique uses a high-speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Direct sequence
B	Phase compandored spread spectrum
C	Binary phase-shift keying
D	Frequency hopping

43. - E9A04

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

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

44. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the beamwidth?

Select	Answer
A	30 degrees
B	50 degrees
C	75 degrees
D	25 degrees

45. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

Select	Answer
A	A figure-8 oriented along the axis of the array
B	Omni-directional
C	Cardioid
D	A figure-8 broadside to the axis of the array

46. - E9D05

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The SWR is reduced
C	The front-to-back ratio increases
D	The frequency response is widened over the whole frequency band

47. - E9E09

Which of the following is used to shunt-feed a grounded tower at its base?

Select	Answer
A	Gamma match
B	Hairpin match
C	Double-bazooka match
D	All these choices are correct

48. - E9F08

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	Foam dielectric has lower loss per unit of length
B	All these choices are correct
C	Foam dielectric has lower safe operating voltage limits
D	Foam dielectric has higher velocity factor

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The voltage axis
C	The current axis
D	The resistance axis

50. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It should be configured as a four-sided loop
B	Its overall length must not exceed 1/4 wavelength
C	It should be one or more wavelengths long
D	It must be mounted more than 1 wavelength above ground

Figure E5-1

Figure E9-1

Figure E9-3