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

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1. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polymorphic silicon
B	Polychlorinated biphenyls
C	Polytetrafluoroethylene
D	Polyethylene

2. - E1A14

Except in some parts of Alaska, what is the maximum power permitted on the 630 meter band?

Select	Answer
A	1 watt EIRP
B	50 watts PEP
C	5 watts EIRP
D	100 watts PEP

3. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation on all frequencies below 30 MHz
B	The amateur station must cease operation
C	The amateur station must cease operation on all frequencies above 30 MHz
D	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	170 Hz
B	2.8 kHz
C	60 Hz
D	1.5 kHz

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 local repeater or linked repeater station
C	All these choices are correct
D	A space station, beacon station, or telecommand station

6. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Friends of the VE
B	All these choices are correct
C	Relatives of the VE as listed in the FCC rules
D	Employees of the VE

7. - E1F10

Who may be the control operator of an auxiliary station?

Select	Answer
A	Any licensed amateur operator
B	Only Amateur Extra Class operators
C	Only General, Advanced or Amateur Extra Class operators
D	Only Technician, General, Advanced or Amateur Extra Class operators

8. - E2A08

Why should effective radiated power to a satellite that uses a linear transponder be limited?

Select	Answer
A	To avoid interfering with terrestrial QSOs
B	To avoid reducing the downlink power to all other users
C	To prevent the satellite from emitting out-of-band signals
D	To prevent creating errors in the satellite telemetry

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	90
B	60
C	30
D	120

10. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?

Select	Answer
A	At the top of each band, usually in a segment reserved for contests
B	In the middle of the band, usually 25 kHz above the national calling frequency
C	In the weak signal segment of the band, with most of the activity near the calling frequency
D	In the middle of each band, usually on the national calling frequency

11. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	PACTOR
B	AMTOR
C	802.11
D	AX.25

12. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	300-baud packet
B	MFSK16
C	PSK31
D	170 Hz shift, 45-baud RTTY

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves that circle the Earth
B	Waves with an electric field bent into a circular shape
C	Waves with a rotating electric field
D	Waves produced by a loop antenna

14. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

Select	Answer
A	7500 miles
B	5000 miles
C	2500 miles
D	1000 miles

15. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Vertical
B	Horizontal
C	Circular
D	Elliptical

16. - E4A02

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

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

17. - E4B07

What do the subscripts of S parameters represent?

Select	Answer
A	Frequency order of the measurements
B	The relative time between measurements
C	The port or ports at which measurements are made
D	Relative quality of the data

18. - E4C02

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

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

19. - E4D11

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

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

20. - E4E10

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	A malfunctioning illuminated advertising display
B	A defective doorbell or doorbell transformer inside a nearby residence
C	Arcing contacts in a thermostatically controlled device
D	All these choices are correct

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. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	68.2 degrees with the voltage leading the current
B	14.0 degrees with the voltage lagging the current
C	68.2 degrees with the voltage lagging the current
D	14.0 degrees with the voltage leading the current

23. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what do the axes represent?

Select	Answer
A	The X axis represents the magnitude and the Y axis represents the phase angle
B	The X axis represents the phase angle and the Y axis represents the magnitude
C	The X axis represents the reactive component and the Y axis represents the resistive component
D	The X axis represents the resistive component and the Y axis represents the reactive component

24. - E5D15

What is the power factor of an RL circuit having a 45-degree phase angle between the voltage and the current?

Select	Answer
A	0.5
B	0.866
C	0.707
D	1.0

25. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Alpha cutoff frequency
B	Alpha rejection frequency
C	Beta cutoff frequency
D	Corner frequency

26. - E6B06

Which of the following is a common use of a Schottky diode?

Select	Answer
A	As a constant voltage reference in a power supply
B	As a VHF/UHF mixer or detector
C	As a variable capacitance in an automatic frequency control circuit
D	As a rectifier in high current power supplies

27. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A logic circuit that can be modified during use
B	A type of transistor whose gain can be changed by digital logic circuits
C	Programmable equipment used for testing digital logic integrated circuits
D	A programmable collection of logic gates and circuits in a single integrated circuit

28. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Steel-core toroids
B	Electrolytic capacitors
C	Butterworth filters
D	Ferrite beads

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 junction voltage drop
C	Higher electron mobility
D	Lower transconductance

30. - E6F03

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

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

31. - E7A11

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

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

32. - E7B11

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

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

33. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a band-pass filter
B	It is a high-pass filter
C	It is a low-pass filter
D	It is a notch filter

34. - E7D12

What is the dropout voltage of an analog voltage regulator?

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

35. - E7E10

How does a diode envelope detector function?

Select	Answer
A	By sensing the change of reactance in the diode with respect to frequency
B	By breakdown of the Zener voltage
C	By rectification and filtering of RF signals
D	By mixing signals with noise in the transition region of the diode

36. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

Select	Answer
A	Sample width in bits
B	Processor latency
C	Sample rate
D	Sample clock phase noise

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	-0.23 volts
B	2.3 volts
C	0.23 volts
D	-2.3 volts

38. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Broadband noise
B	Nyquist limit noise
C	Spurious signals at discrete frequencies
D	Digital conversion noise

39. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	2.5 to 1
B	100 to 1
C	1 to 1
D	25 to 1

40. - E8B10

What is frequency division multiplexing?

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

41. - E8C04

What technique minimizes the bandwidth of a PSK31 signal?

Select	Answer
A	Zero-sum character encoding
B	Reed-Solomon character encoding
C	Use of sinusoidal data pulses
D	Use of trapezoidal data pulses

42. - E8D08

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

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

43. - E9A03

What is the radiation resistance of an antenna?

Select	Answer
A	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
B	The combined losses of the antenna elements and feed line
C	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
D	The specific impedance of the antenna

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

Select	Answer
A	38 dB
B	28 dB
C	3 dB
D	15 dB

45. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole configured to provide forward gain
B	A half-wave dipole with an additional parallel wire connecting its two ends
C	A type of ground-plane antenna
D	A dipole one-quarter wavelength long

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	Improved radiation efficiency
D	Higher losses

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	Velocity factor
D	Characteristic impedance

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	Smaller reflection coefficient
C	Higher SWR
D	Lower velocity factor

49. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	SWR
B	Frequency
C	Points with constant reactance
D	Points with constant resistance

50. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It provides diversity reception that cancels multipath signals
B	It modifies the pattern of a DF antenna array to provide a null in one direction
C	It increases the sensitivity of a DF antenna array
D	It allows DF antennas to receive signals at different vertical angles

Figure E7-1

Figure E7-3