US Amateur Radio - Amateur Extra (Element 4, 2016-2020) Practice Test

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1. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	50 watts PEP effective radiated power relative to an isotropic radiator
B	50 watts PEP effective radiated power relative to a dipole
C	100 watts PEP effective radiated power relative to an isotropic radiator
D	100 watts PEP effective radiated power relative to the gain of a half-wave dipole

2. - 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 at random without the proper call sign identification
C	Any transmitted signal that unintentionally interferes with another licensed radio station
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only auxiliary, repeater or space stations
B	Only earth stations, repeater stations or model craft
C	Only auxiliary, beacon or space stations
D	Only beacon, repeater or space stations

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	Only General, Advanced or Amateur Extra Class
B	Only Amateur Extra Class
C	All except Technician Class
D	Any class with appropriate operator privileges

5. - E1E09

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

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

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A08

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

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

8. - E2B10

Which of the following is an acceptable bandwidth for Digital Radio Mondiale (DRM) based voice or SSTV digital transmissions made on the HF amateur bands?

Select	Answer
A	10 KHz
B	3 KHz
C	20 KHz
D	15 KHz

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Select	Answer
A	Switch to a higher frequency HF band
B	Wait 24 hours before attempting another communication on the band
C	Switch to a lower frequency HF band
D	Wait 90 minutes or so for the signal degradation to pass

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Store-and-forward
B	Multi-satellite relaying
C	Digipeating
D	Node hopping

11. - E2E08

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

Select	Answer
A	PACTOR
B	AMTOR
C	Hellschreiber
D	RTTY

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	The rain must be within radio range of both stations
B	Rain droplets must be electrically charged
C	Rain droplets must be within the E layer
D	All of these choices are correct

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Noon
B	Afternoon or early evening
C	Late at night
D	Morning

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Increased transequatorial propagation likely
B	Long-path propagation is occurring
C	A solar flare has occurred
D	A meteor ping

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A logic analyzer
B	A wattmeter
C	A spectrum analyzer
D	A time-domain reflectometer

16. - E4B10

Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?

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

17. - E4C16

Which of the following is caused by missing codes in an SDR receiver's analog-to-digital converter?

Select	Answer
A	Excess output level
B	Loss of sensitivity
C	Distortion
D	Overload

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
B	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
C	When the signals from the transmitters are reflected in phase from airplanes passing overhead
D	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By turning off the AC power line main circuit breaker and listening on a battery operated radio
B	By observing the AC power line waveform with an oscilloscope
C	By observing the AC power line voltage with a spectrum analyzer
D	By checking the power line voltage with a time domain reflectometer

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Parasitic effects are minimized
B	Internal voltages and circulating currents increase
C	Fewer components are needed for the same performance
D	Phase shift can become uncontrolled

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	110 seconds
B	55 seconds
C	440 seconds
D	220 seconds

22. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

Select	Answer
A	The difference between the resistive and reactive components
B	The sum of the reactive and resistive components
C	Resistive component
D	Reactive component

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

Select	Answer
A	2000 watts
B	400 watts
C	50 watts
D	80 watts

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	1
B	3
C	6
D	2

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As a constant current source
B	As an RF switch
C	As a constant voltage source
D	As a high voltage rectifier

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about one-half the power supply voltage
B	Input signals are stronger
C	The input switching threshold is about two times the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D12

What is the definition of saturation in a ferrite core inductor?

Select	Answer
A	The inductor windings are over coupled
B	Adjacent inductors become over-coupled
C	The inductor's voltage rating is exceeded causing a flashover
D	The ability of the inductor's core to store magnetic energy has been exceeded

28. - E6E08

How is voltage from a power supply normally furnished to the most common type of monolithic microwave integrated circuit (MMIC)?

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

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Silicon
B	Cadmium Sulfide
C	Copper oxide
D	Selenium

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Astable multivibrator
B	Monostable multivibrator
C	J-K flip-flop
D	T flip-flop

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Increased overall intelligibility
B	Signal inversion
C	Signal distortion and excessive bandwidth
D	Reduced intermodulation products

32. - E7C01

How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network's input and output?

Select	Answer
A	An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
B	Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
C	A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between input and output
D	Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground

33. - E7D10

What is the primary reason that a high-frequency switching type high voltage power supply can be both less expensive and lighter in weight than a conventional power supply?

Select	Answer
A	The inverter design does not require any output filtering
B	It uses a diode bridge rectifier for increased output
C	The high frequency inverter design uses much smaller transformers and filter components for an equivalent power output
D	It uses a large power factor compensation capacitor to create free power from the unused portion of the AC cycle

34. - E7E09

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

Select	Answer
A	Mixer blanking occurs
B	Automatic limiting occurs
C	Spurious mixer products are generated
D	A beat frequency is generated

35. - E7F04

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

Select	Answer
A	Emulation of quartz crystal filter characteristics
B	A frequency synthesizer removes the unwanted sidebands
C	Combine signals with a quadrature phase relationship
D	Mixing products are converted to voltages and subtracted by adder circuits

36. - E7G04

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

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

37. - E7H11

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

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

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	Data
B	All of these choices are correct
C	Video signals
D	Human speech

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

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

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Extended Binary Coded Decimal Interchange Code
B	Binary Coded Decimal Code
C	Excess 3 code
D	Gray code

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	The receiver is always equipped with a digital blanker
D	Signals not using the spread spectrum algorithm are suppressed in the receiver

42. - E9A04

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

Select	Answer
A	Sunspot activity and time of day
B	Antenna height, conductor length/diameter ratio and location of nearby conductive objects
C	The settings of an antenna tuner at the transmitter
D	Transmission-line length

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The E-field and H-field patterns may reverse
B	Feed point impedance may become negative
C	The gain may change depending on frequency
D	Element spacing limits could be exceeded

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It reflects the standing waves on the antenna elements back to the transmitter
C	It changes the radiation pattern from horizontal to vertical polarization
D	It changes the radiation pattern from bidirectional to unidirectional

45. - E9D13

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 frequency response is widened over the whole frequency band
D	The front-to-back ratio increases

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	An SWR greater than 1:1
B	A reflection coefficient greater than 1
C	A dielectric constant greater than 1
D	An SWR less than 1:1

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Characteristic impedance
B	Standing wave ratio
C	Velocity factor
D	Surge impedance

48. - E9G04

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

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

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

50. - 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	Zinc oxide
B	Beryllium Oxide
C	Uranium Hexafluoride
D	Mica

Figure E6-2