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	60 meter band
B	30 meter band
C	12 meter band
D	17 meter band

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

3. - 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	When agreed upon by the sending or receiving station
D	Never

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	5
B	4
C	3
D	2

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 W
B	10 W
C	1 W
D	1.5 kW

7. - E2A01

What is the direction of an ascending pass for an amateur satellite?

Select	Answer
A	From south to north
B	From east to west
C	From west to east
D	From north to south

8. - E2B13

How many lines are commonly used in each frame of an amateur slow-scan color television picture?

Select	Answer
A	180 or 360
B	60 or 100
C	128 or 256
D	30 or 60

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	The acceptable practice of manually posting the call signs of stations on a spotting network
B	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
C	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
D	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	Hellschreiber
B	FSK441
C	APRS
D	WSPR

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	MFSK
B	RTTY
C	PSK31
D	Winlink

12. - E3A13

Which emission mode is best for aurora propagation?

Select	Answer
A	RTTY
B	CW
C	FM
D	SSB

13. - E3B05

Which amateur bands typically support long-path propagation?

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

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	Twice as great
B	Four times as great
C	50 percent greater
D	10 percent greater

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Input impedance
B	Sample resolution
C	Sampling rate
D	Input capacitance

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	Low impedance input
B	High impedance input
C	High reluctance input
D	Low reluctance input

17. - E4C16

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

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

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

Select	Answer
A	Desensitization
B	Cross-modulation interference
C	Squelch gain rollback
D	Quieting

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
B	The broadcast station is transmitting an over-modulated signal
C	Your station receiver IF amplifier stage is defective
D	You are receiving sky wave signals from a distant station

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	218.3 kHz
B	436.6 kHz
C	31.4 kHz
D	15.7 kHz

21. - E5B06

What is susceptance?

Select	Answer
A	The magnetic impedance of a circuit
B	The ratio of magnetic field to electric field
C	A measure of the efficiency of a transformer
D	The inverse of reactance

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 8
B	Point 1
C	Point 5
D	Point 3

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	80 watts
B	2000 watts
C	50 watts
D	400 watts

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	N-type
B	Insulated gate
C	Bipolar
D	P-type

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Extremely high reverse breakdown voltage
B	Ability to dissipate large amounts of power
C	Reverse bias controls its forward voltage drop
D	A large region of intrinsic material

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The comparator enters latch-up
B	The IC input can be damaged
C	The comparator changes its output state
D	The feedback loop becomes unstable

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

Select	Answer
A	Ferrite toroids are easier to use with surface mount technology
B	Ferrite toroids generally have better temperature stability
C	Ferrite toroids generally have lower initial permeability
D	Ferrite toroids generally require fewer turns to produce a given inductance value

28. - E6E01

Which of the following is true of a charge-coupled device (CCD)?

Select	Answer
A	It is a CMOS analog-to-digital converter
B	It is used in a battery charger circuit
C	Its phase shift changes rapidly with frequency
D	It samples an analog signal and passes it in stages from the input to the output

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	An ordinary metal
B	A crystalline semiconductor
C	A liquid semiconductor
D	A heavy metal

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It switches momentarily to the opposite binary state and then returns to its original state after a set time
B	It produces a continuous square wave oscillating between 1 and 0
C	It maintains a constant output voltage, regardless of variations in the input voltage
D	It stores one bit of data in either a 0 or 1 state

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

Select	Answer
A	High power gain
B	Low bandwidth
C	High filament voltage
D	Low input impedance

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Lower losses
B	Higher efficiency
C	Greater transformation range
D	Greater harmonic suppression

33. - E7D12

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

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

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

Select	Answer
A	An automatic band-switching circuit
B	An FM generator circuit
C	A circuit for detecting FM signals
D	A circuit for filtering two closely adjacent signals

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters are easier to implement for a given set of passband rolloff requirements
B	FIR filters can respond faster to impulses
C	All of these choices are correct
D	FIR filters delay all frequency components of the signal by the same amount

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	24
B	47
C	94
D	0.21

37. - E7H08

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

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

38. - E8A06

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

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

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	0.214
B	0.47
C	2.14
D	47

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 26 Hz
B	Approximately 104 Hz
C	Approximately 52 Hz
D	Approximately 13 Hz

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It contains fewer information bits per character than any other code
B	It includes built in error correction features
C	It uses one character as a shift code to send numeric and special characters
D	It is possible to transmit both upper and lower case text

42. - E9A08

What is meant by antenna bandwidth?

Select	Answer
A	The frequency range over which an antenna satisfies a performance requirement
B	The angle between the half-power radiation points
C	Antenna length divided by the number of elements
D	The angle formed between two imaginary lines drawn through the element ends

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Polar plots of the far field elevation and azimuth patterns
B	Antenna gain
C	SWR vs frequency charts
D	All of these choices are correct

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole one-quarter wavelength long
B	A type of ground-plane antenna
C	A dipole consisting of one wavelength of wire forming a very thin loop
D	A dipole configured to provide forward gain

45. - E9D07

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

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

46. - E9E13

What is a use for a Wilkinson divider?

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

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	An inductive reactance
B	A capacitive reactance
C	The same as the characteristic impedance of the line
D	The same as the input impedance to the final generator stage

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The reactance axis
B	The voltage axis
C	The resistance axis
D	The current axis

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It automatically cancels ignition noise in mobile installations
B	It eliminates tracking errors caused by strong out-of-band signals
C	It is electro statically balanced against ground, giving better nulls
D	It allows stations to communicate without giving away their position

50. - E0A08

What does SAR measure?

Select	Answer
A	Signal Amplification Rating
B	The rate at which RF energy is absorbed by the body
C	Synthetic Aperture Ratio of the human body
D	The rate of RF energy reflected from stationary terrain

Figure E5-2

Figure E7-4

Figure E9-3