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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Notify the nearest FCC Field Engineer's office
B	Discontinue forwarding the communication as soon as you become aware of it
C	Notify the originating station that the communication does not comply with FCC rules
D	Discontinue forwarding all messages

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	2.0
B	1.0
C	0.5
D	3.0

3. - E1C05

When may an automatically controlled station originate third party communications?

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

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	6 meters, 2 meters, and 1.25 meters
B	2 meters and 1.25 meters
C	2 meters
D	6 meters and 2 meters

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	Have each applicant sign an affidavit stating that all session rules were followed
B	The exam proctor observes the applicants and reports any violations
C	Use a real-time video link and the Internet to connect the exam session to the observing VEs
D	Record the exam session on video tape for later review by the VE team

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
B	All of these choices are correct
C	The transmission must not be used to obscure the meaning of any communication
D	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

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

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Spectral Intensity
B	Luminance
C	Chroma
D	Hue

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	An optical cable connection between the USB ports of 2 separate computers
B	A 440 MHz transceiver with a 9600 baud modem
C	A standard wireless router running custom software
D	A 2 meter VHF transceiver with a 1200 baud modem

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	All of these choices are correct
B	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
C	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
D	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	31 Hz
B	2.16 kHz
C	550 Hz
D	316 Hz

12. - E3A17

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves produced by a loop antenna
B	Waves with a rotating electric field
C	Waves with an electric field bent into a circular shape
D	Waves that circle the Earth

13. - E3B07

Which of the following could account for hearing an echo on the received signal of a distant station?

Select	Answer
A	High D layer absorption
B	Transmit frequency is higher than the MUF
C	Receipt of a signal by more than one path
D	Meteor scatter

14. - E3C09

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

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

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
B	It amplifies low level signals for more accurate counting
C	It divides a higher frequency signal so a low-frequency counter can display the input frequency
D	It prevents oscillation in a low-frequency counter circuit

16. - E4B13

Which S parameter is equivalent to forward gain?

Select	Answer
A	S12
B	S21
C	S11
D	S22

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	2.4 kHz
B	4.8 kHz
C	4.2 kHz
D	1 kHz

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A properly terminated circulator at the output of the transmitter
B	A Class D final amplifier
C	A band-pass filter in the feed line between the transmitter and receiver
D	A Class C final amplifier

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

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

20. - E5A09

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

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

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

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

22. - E5C06

What does the impedance 50-j25 represent?

Select	Answer
A	25 ohms resistance in series with 50 ohms inductive reactance
B	50 ohms resistance in series with 25 ohms inductive reactance
C	50 ohms resistance in series with 25 ohms capacitive reactance
D	25 ohms resistance in series with 50 ohms capacitive reactance

23. - E5D01

What is the result of skin effect?

Select	Answer
A	Thermal effects on the surface of the conductor decrease the impedance
B	As frequency increases, RF current flows in a thinner layer of the conductor, closer to the surface
C	As frequency decreases, RF current flows in a thinner layer of the conductor, closer to the surface
D	Thermal effects on the surface of the conductor increase the impedance

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	6
B	5
C	2
D	4

25. - E6B13

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

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

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	A PGA contains its own internal power supply
B	Complex logic functions can be created in a single integrated circuit
C	All of these choices are correct
D	Many similar gates are less expensive than a mixture of gate types

27. - E6D07

What is the usable frequency range of inductors that use toroidal cores, assuming a correct selection of core material for the frequency being used?

Select	Answer
A	From a few kHz to no more than 30 MHz
B	From about 100 kHz to at least 1000 GHz
C	From approximately 10 Hz to no more than 3000 kHz
D	From less than 20 Hz to approximately 300 MHz

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Ground-plane construction
B	Wave-soldering construction
C	Point-to-point construction
D	Microstrip construction

29. - E6F14

Which of the following is true of LCD displays?

Select	Answer
A	All of these choices are correct
B	They are hard to view in high ambient light conditions
C	They only display alphanumeric symbols
D	They may be hard view through polarized lenses

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It adds two decimal numbers together
B	It produces one output pulse for every ten input pulses
C	It produces ten output pulses for every input pulse
D	It decodes a decimal number for display on a seven segment LED display

31. - E7B18

What is a characteristic of a grounded-grid amplifier?

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

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A passive op-amp filter
B	An active LC filter
C	A Butterworth filter
D	A Chebyshev filter

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Switching voltage regulator
B	Emitter follower
C	Linear voltage regulator
D	Grounded emitter amplifier

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce AM signals by using an electrically variable inductance or capacitance
B	To produce PM signals by using an electrically variable resistance
C	To produce AM signals by using an electrically variable resistance
D	To produce PM signals by using an electrically variable inductance or capacitance

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At half the rate of the highest frequency component of the signal
B	At four times the rate of the highest frequency component of the signal
C	At the same rate as the highest frequency component of the signal
D	At twice the rate of the highest frequency component of the signal

36. - E7G04

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

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

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Negative feedback and balanced feedback
B	Armstrong and deForest
C	Pierce and Zener
D	Colpitts and Hartley

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Harmonic regeneration
B	Level shifting
C	Sequential sampling
D	Phase reversal

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Quieting index
B	FM compressibility
C	Percentage of modulation
D	Modulation index

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	15.36 kHz
C	9.6 kHz
D	5.76 kHz

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth
B	Foreign language characters can be sent
C	The signal can overpower interfering signals
D	Faster transmission rate

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The specific impedance of the antenna
B	The combined losses of the antenna elements and feed line
C	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
D	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	15 dB
B	24 dB
C	28 dB
D	3 dB

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

Select	Answer
A	A Figure-8 broadside to the axis of the array
B	Omni-directional
C	A Figure-8 end-fire along the axis of the array
D	Cardioid

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	Gain is reduced
B	More common-mode current is present on the feed line
C	SWR bandwidth increases
D	SWR bandwidth decreases

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Velocity factor
B	Characteristic impedance
C	Reflection coefficient
D	Dielectric constant

47. - E9F11

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

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

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Impedance axis
B	Prime axis
C	Polar axis
D	Reactance axis

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

50. - E0A08

What does SAR measure?

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

Figure E6-2

Figure E7-3

Figure E9-2

Figure E9-3