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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	1 kHz above the lower band edge
B	The exact lower band edge
C	300 Hz above the lower band edge
D	3 kHz above the lower band edge

2. - E1B01

Which of the following constitutes a spurious emission?

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

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	All of these choices are correct
C	Messages intended for connection to users of the maritime satellite service
D	Business-related messages for non-profit organizations

4. - E1D04

What is an Earth station in the amateur satellite service?

Select	Answer
A	An amateur station that is not able to communicate using amateur satellites
B	An amateur station that transmits telemetry consisting of measurement of upper atmosphere
C	An amateur station within 50 km of the Earth's surface intended for communications with amateur stations by means of objects in space
D	Any amateur station on the surface of the Earth

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	A fine of up to $1000 per occurrence
C	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
D	All of these choices are correct

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To allow regular operation on Land Mobile channels
B	To provide additional spectrum for personal use
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

7. - E2A11

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

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

8. - E2B16

Which is a video standard used by North American Fast Scan ATV stations?

Select	Answer
A	PAL
B	NTSC
C	Scottie
D	DRM

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Store and forward on the 440 MHz band
B	Frequency division multiplex in the 24 GHz band
C	Multiple Frequency Shift Keying in the 10 GHz band
D	Spread spectrum in the 2.4 GHz band

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	PACTOR
B	802.11
C	AX.25
D	AMTOR

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	By exchanging ACK/NAK packets
B	It depends on the lunar phase
C	Alternating transmissions at 1 minute intervals
D	Stations take turns on alternate days

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	The rain must be within radio range of both stations
B	Rain droplets must be electrically charged
C	All of these choices are correct
D	Rain droplets must be within the E layer

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Any time
B	Early evening
C	Around sunset
D	Around sunrise

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	Downward bending due to density variations in the atmosphere
B	D-region skip
C	Downward bending due to aurora refraction
D	E-region skip

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	A spectrum analyzer
B	A Q meter
C	An ohmmeter
D	An antenna analyzer

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S12
B	S22
C	S21
D	S11

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

Select	Answer
A	13.845 MHz
B	15.210 MHz
C	14.755 MHz
D	14.445 MHz

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Raise the receiver IF frequency
B	Switch from fast AGC to slow AGC
C	Decrease the RF bandwidth of the receiver
D	Increase the receiver front end gain

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	Nearby signals may appear to be excessively wide even if they meet emission standards
B	Received audio in the speech range might have an echo effect
C	The audio frequency bandwidth of the received signal might be compressed
D	FM signals can no longer be demodulated

20. - E5A05

What is the magnitude of the current at the input of a series RLC circuit as the frequency goes through resonance?

Select	Answer
A	Maximum
B	Minimum
C	L/R
D	R/L

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	440 seconds
B	220 seconds
C	110 seconds
D	55 seconds

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 6
D	Point 2

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

24. - E6A08

What term indicates the frequency at which the grounded-base current gain of a transistor has decreased to 0.7 of the gain obtainable at 1 kHz?

Select	Answer
A	Alpha cutoff frequency
B	Alpha rejection frequency
C	Beta cutoff frequency
D	Corner frequency

25. - E6B11

What is used to control the attenuation of RF signals by a PIN diode?

Select	Answer
A	Capacitance of an RF coupling capacitor
B	Forward DC bias current
C	Reverse voltage larger than the RF signal
D	A sub-harmonic pump signal

26. - E6C11

In Figure E6-5, what is the schematic symbol for the NOT operation (inverter)?

Select	Answer
A	2
B	5
C	4
D	6

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Teflon and Delrin
B	Polystyrene and polyethylene
C	Cobalt and aluminum
D	Ferrite and brass

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Low leakage doubly insulated package
B	Two chips in each package (Dual In Package)
C	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)
D	Package mounts in a direct inverted position

29. - E6F10

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

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

30. - E7A06

What is a characteristic of a monostable multivibrator?

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

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Self bias
B	Output load resistor
C	Emitter bypass
D	Fixed bias

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	An all-pass filter
B	A band-pass filter
C	A Pi-network filter
D	A notch filter

33. - E7D12

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

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

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The lowest frequency band that the transmitter or receiver covers
B	The frequency components present in the modulating signal
C	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
D	The unmodulated bandwidth of the transmitted signal

35. - E7F03

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

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

36. - E7G05

How can unwanted ringing and audio instability be prevented in a multi-section op-amp RC audio filter circuit?

Select	Answer
A	Restrict both gain and Q
B	Restrict gain but increase Q
C	Increase both gain and Q
D	Restrict Q but increase gain

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Wide-band AF and RF power amplification
B	Comparison of two digital input signals, digital pulse counter
C	Frequency synthesis, FM demodulation
D	Photovoltaic conversion, optical coupling

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

Select	Answer
A	A sawtooth wave
B	A square wave
C	A sine wave
D	A cosine wave

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	Percentage of modulation
C	FM compressibility
D	Modulation index

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	Baud is only used for RTTY
B	Symbol rate is only used for packet-based modes
C	They are the same
D	Baud is twice the symbol rate

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
D	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	14.15 dB
B	12.5 dB
C	9.85 dB
D	6.17 dB

43. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?

Select	Answer
A	Ground conductivity will not be accurately modeled
B	The resulting design will favor radiation of harmonic energy
C	The computed feed point impedance may be incorrect
D	The antenna will become mechanically unstable

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	450 ohms
B	50 ohms
C	72 ohms
D	300 ohms

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To lower the losses
B	To increase the SWR bandwidth
C	To cancel capacitive reactance
D	To lower the Q

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
B	It allows single-band antennas to operate on other bands
C	It makes sure the antenna has a low-angle radiation pattern
D	It ensures that each driven element operates in concert with the others to create the desired antenna pattern

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Smaller reflection coefficient
B	Lower velocity factor
C	Higher SWR
D	Lower loss

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Coaxial-length circles
B	Standing wave ratio circles
C	Radiation-pattern circles
D	Antenna-length circles

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station uses three different antennas to plot the location of the signal source
B	Antenna headings from several different receiving locations are used to locate the signal source
C	The geometric angles of sky waves from the source are used to determine its position
D	A fixed receiving station plots three headings to the signal source

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

Figure E5-2

Figure E6-5

Figure E7-1