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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	17 meter band
B	60 meter band
C	12 meter band
D	30 meter band

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in New Mexico surrounding the White Sands Test Area
B	An area surrounding the National Radio Astronomy Observatory
C	An area in Puerto Rico surrounding the Arecibo Radio Telescope
D	An area in Florida surrounding Cape Canaveral

3. - E1C10

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

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

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	Any amateur station designated by NASA
C	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
D	All of these choices are correct

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 70%
B	Minimum passing score of 80%
C	Minimum passing score of 74%
D	Minimum passing score of 77%

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	It was imported from a manufacturer in another country and was certificated by that country's government
D	The equipment dealer assembled it from a kit

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	An isotropic antenna
B	A linearly polarized antenna
C	A circularly polarized antenna
D	A log-periodic dipole array

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
B	They are not permitted above 54 MHz
C	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
D	None; they are allowed on all amateur frequencies

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	The ARRL section of the remote station
B	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
C	No additional indicator is required
D	/R# where # is the district of the remote station

10. - E2D06

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

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

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	48 baud
B	110 baud
C	300 baud
D	1200 baud

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Sprites and jets
B	Lightning discharges
C	Warm and cold fronts
D	Gray-line

13. - E3B05

Which amateur bands typically support long-path propagation?

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

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Higher levels of solar UV radiation
B	Increasing disruption of the geomagnetic field
C	An increase in the critical frequency
D	Decreasing disruption of the geomagnetic field

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	An ohmmeter
B	An antenna analyzer
C	A spectrum analyzer
D	A Q meter

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It can display results directly in Smith chart format
B	It provides an excellent match under all conditions
C	It is relatively immune to drift in the signal generator source
D	It is very precise in obtaining a signal null

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It reduces receiver sensitivity
B	It limits the receiver's ability to receive strong signals
C	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
D	It decreases receiver third-order intermodulation distortion dynamic range

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To store often-used frequencies
B	To increase rejection of unwanted signals
C	To allow selection of the optimum RF amplifier device
D	To provide a range of AGC time constants

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	A common-mode signal at the frequency of the radio transmitter
B	Harmonics of the AC power line frequency
C	An electrical-sparking signal
D	A differential-mode signal at the AC power line frequency

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	Approximately equal to capacitive reactance
B	Approximately equal to inductive reactance
C	Approximately equal to circuit resistance
D	High, as compared to the circuit resistance

21. - E5B02

What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial voltage?

Select	Answer
A	An exponential discharge rate of one
B	One time constant
C	One discharge period
D	A discharge factor of one

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 5
B	Point 8
C	Point 1
D	Point 3

23. - E5D04

Why are short connections necessary at microwave frequencies?

Select	Answer
A	To reduce phase shift along the connection
B	To reduce noise figure
C	Because of ground reflections
D	To increase neutralizing resistance

24. - 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	Beta cutoff frequency
C	Alpha rejection frequency
D	Corner frequency

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

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

27. - E6D12

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

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

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	To provide a low-pass frequency response
B	High-voltage insulating ability
C	Enhanced sensitivity to light
D	Better dissipation of heat

29. - E6F04

What is the photovoltaic effect?

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

30. - E7A12

What type of logic defines "0" as a high voltage?

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

31. - E7B12

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

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

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Cascode
B	Pi
C	Omega
D	Pi-L

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

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

34. - E7E10

How does a diode detector function?

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

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	10 bits
B	4 bits
C	8 bits
D	6 bits

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	Partial cancellation of the signal over a range of frequencies
B	An echo caused by a long time delay
C	A reduction in high frequency response
D	Undesired oscillations added to the desired signal

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Wirewound resistors
B	NP0 capacitors
C	Non-inductive resistors
D	Toroidal inductors

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

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

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	EME
B	High speed digital modes
C	OFDM signals are not allowed on amateur bands
D	Extremely low-power contacts

40. - E8C06

What is the necessary bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	0.3 kHz
B	0.1 Hz
C	0.5 kHz
D	1.0 kHz

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Reduce keying waveform rise and fall times
B	Increase keying waveform rise and fall times
C	Low-pass filters at the transmitter output
D	High-pass filters at the transmitter output

42. - E9A05

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

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

43. - E9B03

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-side ratio?

Select	Answer
A	12 dB
B	14 dB
C	18 dB
D	24 dB

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It causes increased SWR
B	It reduces losses in the radiating portion of the antenna
C	It changes the impedance angle of the matching network
D	It reduces low-angle radiation

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Higher losses
B	Improved radiation efficiency
C	Greater structural strength
D	Lower Q

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

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

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Lower velocity factor
B	Higher SWR
C	Lower loss
D	Smaller reflection coefficient

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - 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 increasing either the number of wire turns in the loop or the area of the loop structure or both
C	By winding adjacent turns in opposing directions
D	By increasing the number of wire turns in the loop and reducing the area of the loop structure

50. - E0A02

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

Select	Answer
A	Advise your neighbors of the results of your tests
B	Make sure signals from your station are less than the controlled MPE limits
C	Make sure signals from your station are less than the uncontrolled MPE limits
D	You need only evaluate exposure levels on your own property

Figure E5-2

Figure E7-1

Figure E9-1