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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A05

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

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

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is in an ITU Zone designated for coordination with one or more foreign governments
B	The location is of environmental importance or significant in American history, architecture, or culture
C	The location is of geographical or horticultural importance
D	The location is near an area of political conflict

3. - E1C10

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

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

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
C	6 meters and 2 meters
D	2 meters and 1.25 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	Record the exam session on video tape for later review by the VE team
B	Have each applicant sign an affidavit stating that all session rules were followed
C	Use a real-time video link and the Internet to connect the exam session to the observing VEs
D	The exam proctor observes the applicants and reports any violations

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	53 MHz - 54 MHz
B	420 MHz - 430 MHz
C	440 MHz - 450 MHz
D	222 MHz - 223 MHz

7. - E2A11

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

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

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Specific tone amplitudes
B	Elapsed time
C	Specific tone frequencies
D	A two-tone signal

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	At the top of each band, usually in a segment reserved for contests
B	In the weak signal segment of the band, with most of the activity near the calling frequency
C	In the middle of each band, usually on the national calling frequency
D	In the middle of the band, usually 25 kHz above the national calling frequency

10. - E2D09

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

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

11. - E2E01

Which type of modulation is common for data emissions below 30 MHz?

Select	Answer
A	Pulse modulation
B	Spread spectrum
C	FSK
D	DTMF tones modulating an FM signal

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	A fluttery irregular fading
B	A slow change in the pitch of the CW signal
C	A gradual loss of signal as the Sun rises
D	The returning echo is several Hertz lower in frequency than the transmitted signal

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Transequatorial
B	Long-path
C	Gray-line
D	Sporadic-E

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class B
B	Class A
C	Class M
D	Class X

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. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	A less accurate reading results
B	Cross modulation occurs
C	Harmonics are generated
D	Intermodulation distortion occurs

17. - E4C15

What is usually the primary source of noise that is heard from an HF receiver with an antenna connected?

Select	Answer
A	Receiver front-end noise
B	Detector noise
C	Induction motor noise
D	Atmospheric noise

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression
B	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
C	The difference in dB between the noise floor and the third order intercept point
D	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor

19. - E4E08

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

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

20. - E5A06

What is the magnitude of the circulating current within the components of a parallel LC circuit at resonance?

Select	Answer
A	It equals 2 multiplied by Pi, multiplied by frequency, multiplied by inductance
B	It equals 1 divided by the quantity 2 times Pi, multiplied by the square root of inductance L multiplied by capacitance C
C	It is at a maximum
D	It is at a minimum

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	68.2 degrees with the voltage lagging the current
B	68.2 degrees with the voltage leading the current
C	14.0 degrees with the voltage lagging the current
D	14.0 degrees with the voltage leading the current

22. - E5C07

What is a vector?

Select	Answer
A	The inverse of the sine function
B	The value of a quantity that changes over time
C	A quantity with both magnitude and an angular component
D	The inverse of the tangent function

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is dissipated as kinetic energy in the circuit
B	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
C	It is dissipated as heat in the circuit
D	It is dissipated in the formation of inductive and capacitive fields

24. - E6A16

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

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

25. - E6B05

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

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

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A FET logic family based on bimetallic semiconductors
B	A logic family based on bismuth CMOS devices
C	An integrated circuit logic family using both bipolar and CMOS transistors
D	A logic device with two CMOS circuits per package

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	RF susceptance would increase
B	Harmonics and distortion could result
C	Magnetic flux would increase with frequency
D	Temporary changes of the core permeability could result

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	PLCC
B	DIP
C	Ball grid array
D	SOT

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	12 V
C	0.5 V
D	1.5 V

30. - E7A06

What is a characteristic of a monostable multivibrator?

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

31. - E7B12

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

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

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	Greater transformation range
C	Higher efficiency
D	Greater harmonic suppression

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To cut down on waste heat generated by the power supply
B	To boost the amount of output current
C	To balance the low-voltage filament windings
D	To improve output voltage regulation

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A heterodyne suppressor
B	A pre-emphasis network
C	An audio prescaler
D	A de-emphasis network

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	An adaptive filter
B	An elliptical filter
C	A Hilbert-transform filter
D	A notch filter

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. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Taft, Pierce and negative feedback
B	Taft, Hartley and Pierce
C	Pierce, Fenner and Beane
D	Colpitts, Hartley and Pierce

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	Immunity to out of sequence coding reduces spurious responses
B	All of these choices are correct
C	Very high speed allows digitizing high frequencies
D	Very low power consumption decreases frequency drift

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	Two or more information streams are merged into a baseband, which then modulates the transmitter
C	The transmitted signal is divided into packets of information
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C09

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

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Bit errors in the modem
B	Excessive transmit audio levels
C	Ground loops
D	Excessive numbers of retries

42. - E9A05

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

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

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

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
B	A phased array antenna consisting of multiple loops
C	A multi-band trap antenna
D	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain increases by 3 dB
B	Gain does not change
C	Gain is multiplied by 0.707
D	Gain increases by 6 dB

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Use the universal stub matching technique
B	Use a 50 ohm 1:1 balun between the antenna and feed line
C	Connect a series-resonant LC network across the antenna feed terminals
D	Connect a parallel-resonant LC network across the antenna feed terminals

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

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H11

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

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

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only commercial transmitters
B	Each transmitter operating with a duty-cycle greater than 50 percent
C	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
D	Only the most powerful transmitter

Figure E7-1