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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	No, one of the sidebands of the CW signal will be out of the band
B	Yes, the DX station initiated the contact
C	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz
D	Yes, the displayed frequency is within the 80 meter CW band segment

2. - E1B01

Which of the following constitutes a spurious emission?

Select	Answer
A	Any transmitted signal that unintentionally interferes with another licensed radio station
B	An amateur station transmission made at random without the proper call sign identification
C	A signal transmitted to prevent its detection by any station other than the intended recipient
D	An emission outside its necessary bandwidth that can be reduced or eliminated without affecting the information transmitted

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	18.110 MHz - 18.168 MHz
B	24.940 MHz - 24.990 MHz
C	10.100 MHz - 10.150 MHz
D	29.500 MHz - 29.700 MHz

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	All of these choices are correct
B	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
C	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
D	The space station must cease all transmissions after 5 years

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The VE session manager
B	The VEC coordinating the session
C	The FCC
D	Each administering VE

6. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
B	A line roughly parallel to and south of the U.S.-Canadian border
C	A line roughly parallel to and west of the U.S. Atlantic coastline
D	A line roughly parallel to and east of the U.S. Pacific coastline

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of the Doppler Effect
B	Because of the satellite's low orbital altitude
C	Because the satellite is spinning
D	Because of ionospheric absorption

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	120
B	30
C	60
D	90

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

10. - E2D13

What type of modulation is used for JT65 contacts?

Select	Answer
A	IEEE 802.11
B	RTTY
C	Multi-tone AFSK
D	PSK

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	The protocol version you are using is not the supported by the digital station
B	Another station you are unable to hear is using the frequency
C	Your transmit frequency is incorrect
D	All of these choices are correct

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	2500 miles
B	100 miles to 300 miles
C	10 miles to 50 miles
D	1200 miles

13. - E3B07

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

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

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	UV emissions at 304 angstroms, correlated to solar flux index
B	The ratio of X-Ray flux to radio flux, correlated to sunspot number
C	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
D	The solar emission at 304 GHz, correlated to X-Ray flare levels

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Modulation monitor
B	Network analyzer
C	Bit error rate tester
D	Logic analyzer

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	There is possibly a short to ground in the feed line
B	There is more power going into the antenna
C	There is an impedance mismatch between the antenna and feed line
D	The transmitter is not properly neutralized

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

Select	Answer
A	A narrow IF filter
B	A front-end filter or pre-selector
C	A properly adjusted product detector
D	A notch filter

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	173.35 MHz and 139.40 MHz
B	146.88 MHz and 146.34 MHz
C	146.34 MHz and 146.61 MHz
D	146.10 MHz and 147.30 MHz

19. - E4E07

How can you determine if line noise interference is being generated within your home?

Select	Answer
A	By turning off the AC power line main circuit breaker and listening on a battery operated radio
B	By checking the power line voltage with a time domain reflectometer
C	By observing the AC power line voltage with a spectrum analyzer
D	By observing the AC power line waveform with an oscilloscope

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	23.67 kHz
B	315.6 Hz
C	47.3 kHz
D	157.8 Hz

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	The sign is reversed
B	The susceptance phase angle is the inverse of the reactance phase angle
C	It is unchanged
D	It is shifted by 90 degrees

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Select	Answer
A	Point 5
B	Point 4
C	Point 2
D	Point 6

23. - E5D05

Which parasitic characteristic increases with conductor length?

Select	Answer
A	Permeability
B	Permittivity
C	Inductance
D	Malleability

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Acceptor impurity
B	Insulator impurity
C	N-type impurity
D	Donor impurity

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Much higher reverse voltage breakdown
B	Less forward voltage drop
C	Controlled reverse avalanche voltage
D	Enhanced carrier retention time

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor connected to an op-amp output that only functions when the logic output is false
B	A resistor in a keying circuit used to reduce key clicks
C	A resistor that insures that an oscillator frequency does not drive lower over time
D	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
B	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
C	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
D	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel

28. - E6E07

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

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

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Silicon
B	Cadmium Sulfide
C	Copper oxide
D	Selenium

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	8
B	1
C	4
D	2

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
B	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
C	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
D	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current

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

33. - E7D08

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

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

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	An adaptive filter
B	A crystal-lattice filter
C	A phase-inverting filter
D	A Hilbert-transform filter

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
B	A RF amplifier used in the UHF and microwave regions
C	A digital audio amplifier whose characteristics are determined by components external to the amplifier
D	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

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

38. - E8A13

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

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

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

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Yagi
B	Isotropic antenna
C	Quarter-wave vertical
D	Half-wave dipole

43. - E9B02

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

Select	Answer
A	36 dB
B	14 dB
C	24 dB
D	18 dB

44. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

Select	Answer
A	The main lobe takeoff angle increases in the downhill direction
B	The main lobe takeoff angle decreases in the downhill direction
C	The horizontal beam width decreases in the downhill direction
D	The horizontal beam width increases in the uphill direction

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The frequency response is widened over the whole frequency band
C	The front-to-back ratio increases
D	The SWR is reduced

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element resonance must be lower than the operating frequency
B	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
C	The driven element reactance must be inductive
D	The driven element reactance must be capacitive

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	Very high impedance
B	Very low impedance
C	The same as the characteristic impedance of the transmission line
D	The same as the generator output impedance

48. - E9G05

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

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

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It narrows the bandwidth of the received signal to improve signal to noise ratio
B	It prevents receiver overload which could make it difficult to determine peaks or nulls
C	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
D	It compensates for the effects of an isotropic antenna, thereby improving directivity

50. - E0A10

What toxic material may be present in some electronic components such as high voltage capacitors and transformers?

Select	Answer
A	Polymorphic silicon
B	Polyethylene
C	Polychlorinated Biphenyls
D	Polytetrafluroethylene

Figure E5-2

Figure E7-3

Figure E9-1

Figure E9-3