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

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1. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Mica
B	Zinc oxide
C	Beryllium Oxide
D	Uranium Hexafluoride

2. - E1A14

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

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

3. - E1B10

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

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

4. - E1C01

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

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

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
B	Any amateur station, subject to the privileges of the class of operator license held by the control operator
C	Only those of General, Advanced or Amateur Extra Class operators
D	Only those of Amateur Extra Class operators

6. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	All these choices are correct
B	A fine of up to $1000 per occurrence
C	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
D	A sentence of up to one year in prison

7. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When the control operator is employed by the FCC or another government agency
B	When the total money involved does not exceed $25
C	When neither the amateur nor his or her employer has a pecuniary interest in the communications
D	When transmitting international third-party communications

8. - E2A10

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geostationary
B	Geomagnetic
C	LEO
D	HEO

9. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	No other hardware is needed
B	A special IF converter
C	A special front end limiter
D	A special notch filter to remove synchronization pulses

10. - E2C07

What is the Cabrillo format?

Select	Answer
A	The rules of order for meetings between contest sponsors
B	A standard for submission of electronic contest logs
C	The most common set of contest rules
D	A method of exchanging information during a contest QSO

11. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	High-speed CW identification to avoid fading
B	Storing and forwarding digital messages
C	Time synchronous transmissions alternately from each station
D	Judging optimum transmission times by monitoring beacons reflected from the moon

12. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

13. - E3A09

Which of the following frequency ranges is most suited for meteor scatter communications?

Select	Answer
A	28 MHz - 148 MHz
B	10 MHz - 14 MHz
C	1.8 MHz - 1.9 MHz
D	220 MHz - 450 MHz

14. - E3B07

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become phase locked
B	They are bent toward the magnetic poles
C	They become elliptically polarized
D	They become depolarized

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

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	RF amplitude and time
C	SWR and time
D	SWR and frequency

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
B	Modulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
C	Modulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
D	Modulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter

18. - E4C11

Why can an attenuator be used to reduce receiver overload on the lower frequency HF bands with little or no impact on signal-to-noise ratio?

Select	Answer
A	Signals are attenuated separately from the noise
B	The attenuator has a low-pass filter to increase the strength of lower frequency signals
C	Atmospheric noise is generally greater than internally generated noise even after attenuation
D	The attenuator has a noise filter to suppress interference

19. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The minimum difference in dB between two signals which produce third-order intermodulation products greater than the noise floor
B	The difference in dB between the noise floor and the level of an incoming signal that will cause 1 dB of gain compression
C	The minimum difference in dB between the levels of two FM signals that will cause one signal to block the other
D	The difference in dB between the noise floor and the third-order intercept point

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

21. - E5A10

How is the Q of an RLC series resonant circuit calculated?

Select	Answer
A	Reactance of either the inductance or capacitance divided by the resistance
B	Reactance of the inductance multiplied by the reactance of the capacitance
C	Resistance divided by the reactance of either the inductance or capacitance
D	Reactance of either the inductance or capacitance multiplied by the resistance

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 leading the current
C	68.2 degrees with the voltage lagging the current
D	14.0 degrees with the voltage lagging the current

23. - E5C04

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

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

24. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	To avoid unwanted inductive reactance
B	To maintain component lifetime
C	To increase the thermal time constant
D	All these choices are correct

25. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The change in collector current with respect to base current
B	The frequency at which the current gain is reduced to 0.707
C	The switching speed
D	The breakdown voltage of the base to collector junction

26. - E6B10

In Figure E6-2, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	6
B	1
C	5
D	7

27. - E6C08

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

Select	Answer
A	1
B	4
C	2
D	3

28. - E6D11

Which type of core material decreases inductance when inserted into a coil?

Select	Answer
A	Powdered iron
B	Ferrite
C	Ceramic
D	Brass

29. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	PLCC
B	DIP
C	Ball grid array
D	SOT

30. - E6F03

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

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

31. - E7A02

What is the function of a decade counter?

Select	Answer
A	It decodes a decimal number for display on a seven-segment LED display
B	It produces one output pulse for every 10 input pulses
C	It produces 10 output pulses for every input pulse
D	It decodes a binary number for display on a seven-segment LED display

32. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A temperature compensating load resistor to improve linearity
B	A low-pass filter to remove switching signal components
C	A matched load resistor to prevent damage by switching transients
D	A high-pass filter to compensate for low gain at low frequencies

33. - E7C10

Which of the following filters would be the best choice for use in a 2 meter band repeater duplexer?

Select	Answer
A	An L-C filter
B	A crystal filter
C	A cavity filter
D	A DSP filter

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 series current source
C	A series regulator
D	A shunt regulator

35. - E7E07

What is meant by the term "baseband" in radio communications?

Select	Answer
A	The lowest frequency band that the transmitter or receiver covers
B	The unmodulated bandwidth of the transmitted signal
C	The frequency range occupied by a message signal prior to modulation
D	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency

36. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Mixing products are converted to voltages and subtracted by adder circuits
B	A frequency synthesizer removes the unwanted sidebands
C	Signals are combined in quadrature phase relationship
D	Varying quartz crystal characteristics emulated in digital form

37. - E7G01

What is the typical output impedance of an op-amp?

Select	Answer
A	100 ohms
B	Very high
C	Very low
D	1000 ohms

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

Select	Answer
A	Colpitts, Hartley and Pierce
B	Taft, Hartley and Pierce
C	Taft, Pierce and negative feedback
D	Pierce, Fenner and Beane

39. - E8A11

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

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

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A frequency modulation technique that uses non-harmonically related frequencies
B	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference
C	A bandwidth compression technique using Fourier transforms
D	A digital mode for narrow-band, slow-speed transmissions

41. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is only used for RTTY
B	Baud is twice the symbol rate
C	Symbol rate is only used for packet-based modes
D	They are the same

42. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
B	The frequency of the transmitted signal is changed very rapidly according to a pseudorandom sequence also used by the receiving station
C	A binary bit stream is used to shift the phase of an RF carrier very rapidly in a pseudorandom sequence
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

43. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Transmission-line resistance plus radiation resistance
B	Radiation resistance plus loss resistance
C	Radiation resistance plus space impedance
D	Radiation resistance plus transmission resistance

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

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

46. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to a metal water pipe
C	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
D	A 50-ohm resistor connected to ground

47. - E9E08

What is a use for a Wilkinson divider?

Select	Answer
A	It is used to divide power equally between two 50-ohm loads while maintaining 50-ohm input impedance
B	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
C	It is used to feed high-impedance antennas from a low-impedance source
D	It is used to feed low-impedance loads from a high-impedance source

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

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Voltage and impedance
B	Resistance and reactance
C	Reactance and voltage
D	Resistance and voltage

50. - E9H10

How can the output voltage of a multiple-turn receiving loop antenna be increased?

Select	Answer
A	By reducing the permeability of the loop shield
B	By utilizing high impedance wire for the coupling loop
C	By winding adjacent turns in opposing directions
D	By increasing the number of turns and/or the area

Figure E6-2

Figure E6-3