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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
B	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
C	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use
D	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
B	Any FCC-licensed amateur station except a Technician class
C	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
D	Only those club stations licensed to Amateur Extra class operators

3. - E1C04

What is meant by IARP?

Select	Answer
A	An indication of increased antenna reflected power
B	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas
C	A forecast of intermittent aurora radio propagation
D	The internal amateur radio practices policy of the FCC

4. - 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

5. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Warn the candidate that continued failure to comply will result in termination of the examination
B	Allow the candidate to complete the examination, but invalidate the results
C	Immediately terminate the candidate's examination
D	Immediately terminate everyone's examination and close the session

6. - E1F09

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

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

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	Whether the satellite is in a polar or equatorial orbit
B	The satellite's uplink and downlink frequency bands
C	The satellite's orientation with respect to the Earth
D	The type of signals that can be relayed through the satellite

8. - E2B06

What is vestigial sideband modulation?

Select	Answer
A	Spread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
B	Amplitude modulation in which one complete sideband and a portion of the other are transmitted
C	Narrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
D	A type of modulation in which one sideband is inverted

9. - 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 the call sign of the DX station three times, the words "this is", then your call sign three times
B	Send your full call sign and grid square
C	Send your full call sign once or twice
D	Send only the last two letters of your call sign until you make contact

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	AMTOR
B	170 Hz shift, 45 baud RTTY
C	PSK31
D	300 baud packet

11. - E2E07

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

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

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The D layer
B	The F1 layer
C	The F2 layer
D	The E layer

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	Meteor scatter
D	Receipt of a signal by more than one path

14. - E3C04

What does the value of Bz (B sub Z) represent?

Select	Answer
A	Direction and strength of the interplanetary magnetic field
B	Duration of long-delayed echoes
C	Geomagnetic field stability
D	Critical frequency for vertical transmissions

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	All of these choices are correct
B	Automatic amplitude and frequency numerical readout
C	Storage of traces for future reference
D	Manipulation of time base after trace capture

16. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Temperature coefficient of the logic
B	Time base accuracy
C	Input attenuator accuracy
D	Decade divider accuracy

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	One-half the maximum sampling buffer size
B	The maximum count value of the analog-to-digital converter
C	One-half the maximum sample rate
D	The reference voltage of the analog-to-digital converter

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 Class C final amplifier
D	A band-pass filter in the feed line between the transmitter and receiver

19. - E4E08

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

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

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	1.78 MHz
C	22.36 MHz
D	44.72 MHz

21. - E5B13

What letter is commonly used to represent susceptance?

Select	Answer
A	B
B	G
C	Y
D	X

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Elliptical coordinates
B	Faraday grid
C	Maidenhead grid
D	Rectangular coordinates

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The diameter of the conductor
C	The ratio of the current to the resistance
D	The resistance divided by the current

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free protons
B	Free neutrons
C	Free electrons
D	Holes

25. - E6B12

What is one common use for PIN diodes?

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

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Immune to damage from static discharge
B	Lower power consumption
C	Differential output capability
D	Lower distortion

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Stabilizing current
B	Magnetizing current
C	Excitation current
D	Direct current

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Virtual lead mounting
B	Direct soldering
C	Surface mount
D	Stripped lead

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The effective payback period
B	The open-circuit voltage divided by the short-circuit current under full illumination
C	The output RF power divided by the input DC power
D	The relative fraction of light that is converted to current

30. - E7A12

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

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

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Neutralization
B	Select transistors with high beta
C	Use a resistor in series with the emitter
D	All of these choices are correct

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It introduces negative resistance to cancel the resistive part of impedance
B	It cancels the reactive part of the impedance and changes the resistive part to a desired value
C	Network resistances are substituted for load resistances and reactances are matched to the resistances
D	It introduces transconductance to cancel the reactive part of impedance

33. - E7D11

What circuit element is controlled by a series analog voltage regulator to maintain a constant output voltage?

Select	Answer
A	Reference voltage
B	Pass transistor
C	Switching inductance
D	Error amplifier

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a balanced modulator followed by a filter
B	By using a loop modulator followed by a mixer
C	By using a reactance modulator followed by a mixer
D	By driving a product detector with a DSB signal

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	4 bits
B	10 bits
C	8 bits
D	6 bits

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

Select	Answer
A	1000 ohms
B	Very high
C	100 ohms
D	Very low

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Provide the crystal with a specified parallel inductance
B	Bias the crystal at a specified voltage
C	Provide the crystal with a specified parallel capacitance
D	Bias the crystal at a specified current

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	8
B	256 divided by the gain of the input amplifier
C	8 multiplied by the gain of the input amplifier
D	256

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. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Use of trapezoidal data pulses
B	Use of sinusoidal data pulses
C	Zero-sum character encoding
D	Reed-Solomon character encoding

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
B	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
C	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code
D	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To calculate the front-to-back ratio of the antenna
B	To calculate the front-to-side ratio of the antenna
C	To measure the near-field radiation density from a transmitting antenna
D	To match impedances in order to minimize standing wave ratio on the transmission line

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Next Element Comparison
B	Numerical Electromagnetic Code
C	Numeric Electrical Computation
D	National Electrical Code

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A wideband vertical antenna constructed from precisely tapered aluminum tubing
B	A portable antenna erected using two push support poles
C	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
D	An end fed folded dipole antenna

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	Near the center of the vertical radiator
B	As low as possible on the vertical radiator
C	As close to the transmitter as possible
D	At a voltage node

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	A shunt inductor
B	Pi-L-network
C	A series capacitor
D	Pi-network

47. - E9F09

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 7.2 MHz?

Select	Answer
A	24 meters
B	6.9 meters
C	10 meters
D	50 meters

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Smith chart
B	Elevation angle radiation pattern chart
C	Free space radiation directivity chart
D	Azimuth angle radiation pattern chart

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	High-radiation angle
B	A very sharp single null
C	A very sharp peak
D	Broad band response

50. - E0A08

What does SAR measure?

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

Figure E9-3