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

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1. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Ensure signals from your station are less than the uncontrolled Maximum Permitted Emission (MPE) limits
B	Ensure signals from your station are less than the uncontrolled Maximum Permitted Exposure (MPE) limits
C	Ensure signals from your station are less than the controlled Maximum Permitted Emission (MPE) limits
D	Ensure signals from your station are less than the controlled Maximum Permitted Exposure (MPE) limits

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	300 Hz above the lower band edge
D	The exact lower band edge

3. - E1B10

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

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

4. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When approved by the National Telecommunication and Information Administration
B	Only when transmitting RTTY or data emissions
C	Never
D	When agreed upon by the sending or receiving station

5. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

6. - E1E03

What is a Volunteer Examiner Coordinator?

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

7. - E1F10

Who may be the control operator of an auxiliary station?

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

8. - E2A09

What do the terms L band and S band specify regarding satellite communications?

Select	Answer
A	The 2 meter and 70 centimeter bands
B	The 23 centimeter and 13 centimeter bands
C	Which sideband to use
D	FM and Digital Store-and-Forward systems

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

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 your full call sign once or twice
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 the call sign of the DX station three times, the words this is,then your call sign three times

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Connect
B	Disconnect
C	Unnumbered Information
D	Acknowledgement

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	Hellschreiber
B	AMTOR
C	RTTY
D	PACTOR

13. - E3A04

What do Hepburn maps predict?

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

14. - E3B09

At what time of year is sporadic E propagation most likely to occur?

Select	Answer
A	Around the solstices, especially the summer solstice
B	Around the solstices, especially the winter solstice
C	Around the equinoxes, especially the fall equinox
D	Around the equinoxes, especially the spring equinox

15. - E3C01

What does the radio communication term "ray tracing" describe?

Select	Answer
A	The process in which an electronic display presents a pattern
B	Determining the radiation pattern from an array of antennas
C	Evaluating high voltage sources for x-rays
D	Modeling a radio wave's path through the ionosphere

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	All these choices are correct
B	Antenna analyzers display a time-varying representation of the modulation envelope
C	Antenna analyzers do not need an external RF source
D	Antenna analyzers automatically tune your antenna for resonance

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 harmonically related frequencies and observe the RF output with a logic analyzer
B	Modulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum 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. - E4C12

Which of the following has the largest effect on an SDR receiver's dynamic range?

Select	Answer
A	Anti-aliasing input filter bandwidth
B	CPU register width in bits
C	RAM speed used for data storage
D	Analog-to-digital converter sample width in bits

19. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Positive feedback
B	Too little gain
C	Lack of neutralization
D	Nonlinear circuits or devices

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

21. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 2 multiplied by pi, multiplied by frequency, multiplied by inductance
B	It is at a maximum
C	It equals 1 divided by the quantity 2 times pi, multiplied by the square root of inductance L multiplied by capacitance C
D	It is at a minimum

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

23. - E5C12

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and a 19-picofarad capacitor at 21.200 MHz?

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

24. - E5D11

What is the power factor of an RL circuit having a 60-degree phase angle between the voltage and the current?

Select	Answer
A	0.5
B	1.414
C	1.73
D	0.866

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

26. - E6B03

What type of bias is required for an LED to emit light?

Select	Answer
A	Inductive bias
B	Forward bias
C	Zero bias
D	Reverse bias

27. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
C	A resistor connected to an op-amp output that prevents signals from exceeding the power supply voltage
D	A resistor that ensures that an oscillator frequency does not drift

28. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Non-linear core hysteresis
B	The skin effect
C	Inductive kickback
D	Inter-turn capacitance

29. - E6E08

How is power supplied to the most common type of MMIC?

Select	Answer
A	Through a capacitor and RF choke connected to the amplifier input lead
B	Through a resistor and/or RF choke connected to the amplifier output lead
C	Directly to the bias voltage (VCC IN) lead
D	MMICs require no operating bias

30. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The tendency of a battery to discharge when exposed to light
B	The conversion of light to electrical energy
C	The conversion of voltage to current when exposed to light
D	The conversion of electrical energy to mechanical energy

31. - E7A08

What logical operation does an OR gate perform?

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

32. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common collector
B	Emitter follower
C	Common emitter
D	Common base

33. - E7C10

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

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

34. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-2?

Select	Answer
A	It bypasses rectifier output ripple around D1
B	To provide fixed DC bias for Q1
C	It is a brute force filter for the output
D	To self-resonate at the hum frequency

35. - E7E11

Which type of detector circuit is used for demodulating SSB signals?

Select	Answer
A	Phase comparator
B	Product detector
C	Phase detector
D	Discriminator

36. - E7F04

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

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

37. - E7G03

What is the typical input 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, Pierce and negative feedback
C	Pierce, Fenner and Beane
D	Taft, Hartley and Pierce

39. - E8A04

What is "dither" with respect to analog-to-digital converters?

Select	Answer
A	A small amount of noise added to the input signal to allow more precise representation of a signal over time
B	An error caused by irregular quantization step size
C	An abnormal condition where the converter cannot settle on a value to represent the signal
D	A method of decimation by randomly skipping samples

40. - E8B09

What is deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the audio modulating frequency to the center carrier frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency

41. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By varying the frequency shift of the transmitted signal according to a predefined algorithm
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By transmitting extra data that may be used to detect and correct transmission errors
D	By the receiving station repeating each block of three data characters

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

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

Select	Answer
A	63.2 watts
B	632 watts
C	252 watts
D	159 watts

44. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Method of Moments
B	Calculus differentiation with respect to physical properties
C	Mutual impedance analysis
D	Graphical analysis

45. - E9C09

Which of the following describes a G5RV antenna?

Select	Answer
A	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a�4:1 balun
B	A multi-band trap antenna
C	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
D	A phased array antenna consisting of multiple loops

46. - E9D04

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

Select	Answer
A	To swamp out harmonics
B	To lower the radiation angle
C	To minimize losses
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	450 ohms
B	75 ohms
C	62 ohms
D	50 ohms

48. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	Electrical signals move more slowly in a coaxial cable than in air
B	The characteristic impedance is higher in a parallel feed line
C	Skin effect is less pronounced in the coaxial cable
D	The surge impedance is higher in a parallel feed line

49. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Beam headings and radiation patterns
B	Impedance and SWR values in transmission lines
C	Trigonometric functions
D	Satellite azimuth and elevation bearings

50. - E9H07

Why is RF attenuation used when direction-finding?

Select	Answer
A	To narrow the receiver bandwidth
B	To increase receiver sensitivity
C	To prevent receiver overload which reduces pattern nulls
D	To compensate for isotropic directivity and the antenna effect of feed lines

Figure E5-1

Figure E7-1

Figure E7-2