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

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	3 miles
B	30 miles
C	10 miles
D	1 mile

3. - E1C04

What is meant by IARP?

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

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
B	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
C	All HF bands
D	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands

5. - E1E09

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

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

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

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By calculations using the Keplerian elements for the specified satellite
B	By means of the Doppler data for the specified satellite
C	By subtracting the mean anomaly from the orbital inclination
D	By adding the mean anomaly to the orbital inclination

8. - E2B13

How many lines are commonly used in each frame of an amateur slow-scan color television picture?

Select	Answer
A	30 or 60
B	180 or 360
C	128 or 256
D	60 or 100

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 middle of the band, usually 25 kHz above the national calling frequency
C	In the weak signal segment of the band, with most of the activity near the calling frequency
D	In the middle of each band, usually on the national calling frequency

10. - E2D07

What digital protocol is used by APRS?

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

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Forward Error Correction
B	First Error Correction
C	Final Error Correction
D	Fatal Error Correction

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	Changing electric and magnetic fields propagate the energy
B	The energy propagates through a medium with a high refractive index
C	The waves are reflected by the ionosphere and return to their source
D	Electric and magnetic fields become aligned as they travel

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	6 meters
B	80 meters
C	20 meters
D	10 meters

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Long-path propagation is occurring
B	A solar flare has occurred
C	A meteor ping
D	Increased transequatorial propagation likely

15. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers automatically tune your antenna for resonance
B	Antenna analyzers display a time-varying representation of the modulation envelope
C	All of these choices are correct
D	Antenna analyzers do not need an external RF source

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S12
B	S11
C	S21
D	S22

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

Select	Answer
A	-164 dBm
B	-148 dBm
C	-174 dBm
D	-155 dBm

18. - E4D13

Which of the following can cause receiver desensitization?

Select	Answer
A	Audio bias adjusted too high
B	Strong adjacent channel signals
C	Audio gain adjusted too low
D	Squelch gain misadjusted

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Power line noise
B	Ignition noise
C	Broadband white noise
D	All of these choices are correct

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	Approximately equal to inductive reactance
B	Approximately equal to circuit resistance
C	High, as compared to the circuit resistance
D	Approximately equal to capacitive reactance

21. - E5B05

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

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

22. - E5C09

When using rectangular coordinates to graph the impedance of a circuit, what does the horizontal axis represent?

Select	Answer
A	The difference between the resistive and reactive components
B	Resistive component
C	The sum of the reactive and resistive components
D	Reactive component

23. - E5D15

What is the power factor of an R-L circuit having a 45 degree phase angle between the voltage and the current?

Select	Answer
A	0.866
B	0.707
C	1.0
D	0.5

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	Any FET without a channel
B	An FET that exhibits a current flow between source and drain when no gate voltage is applied
C	An FET that has no current flow between source and drain when no gate voltage is applied
D	Any FET for which holes are the majority carriers

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Tunnel
B	Junction
C	Point contact
D	Zener

26. - E6C11

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

Select	Answer
A	6
B	4
C	5
D	2

27. - E6D08

What is one reason for using powdered-iron cores rather than ferrite cores in an inductor?

Select	Answer
A	Powdered-iron cores generally require fewer turns to produce a given inductance
B	Powdered-iron cores generally have greater initial permeability
C	Powdered-iron cores generally maintain their characteristics at higher currents
D	Powdered-iron cores use smaller diameter wire for the same inductance

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	To provide a low-pass frequency response
B	Better dissipation of heat
C	High-voltage insulating ability
D	Enhanced sensitivity to light

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It increases
B	It becomes unstable
C	It decreases
D	It stays the same

30. - E7A11

What type of logic defines "1" as a high voltage?

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

31. - E7B17

Why are odd-order rather than even-order intermodulation distortion products of concern in linear power amplifiers?

Select	Answer
A	Because they are relatively far in frequency from the desired signal
B	Because they invert the sidebands causing distortion
C	Because they maintain the sidebands, thus causing multiple duplicate signals
D	Because they are relatively close in frequency to the desired signal

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	An automatic notch filter
B	A variable bandwidth crystal lattice filter
C	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
D	A special filter that emphasizes image responses

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A shunt current source
B	A series current source
C	A shunt regulator
D	A series regulator

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce PM signals
B	By varying the tuning of an amplifier tank circuit to produce PM signals
C	By varying the tuning of a microphone preamplifier to produce AM signals
D	By varying the tuning of an amplifier tank circuit to produce AM signals

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Data storage transfer rate
B	Missing codes and jitter
C	Sample clock phase noise
D	Reference voltage level and sample width in bits

36. - E7G03

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

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

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	NP0 capacitors
B	Wirewound resistors
C	Non-inductive resistors
D	Toroidal inductors

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Digital signals always occupy a narrower bandwidth
B	Less complex circuitry is required for digital signal generation and detection
C	Digital signals can be regenerated multiple times without error
D	All of these choices are correct

39. - E8B10

What describes frequency division multiplexing?

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

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 26 Hz
B	Approximately 104 Hz
C	Approximately 13 Hz
D	Approximately 52 Hz

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	More difficult to copy
B	The generation of RF harmonics
C	The generation of key clicks
D	Limits data speed

42. - E9A07

What is meant by antenna gain?

Select	Answer
A	The ratio of the amount of power radiated by an antenna compared to the transmitter output power
B	The ratio of the signal in the forward direction to that in the opposite direction
C	The ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
D	The final amplifier gain minus the transmission line losses

43. - E9B15

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

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

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	An end fed folded dipole antenna
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	A wideband vertical antenna constructed from precisely tapered aluminum tubing

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance decreases and the capacitive reactance increases
B	The radiation resistance decreases and the capacitive reactance decreases
C	The radiation resistance increases and the capacitive reactance decreases
D	The radiation resistance increases and the capacitive reactance increases

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A dielectric constant greater than 1
B	A reflection coefficient greater than 1
C	An SWR greater than 1:1
D	An SWR less than 1:1

47. - E9F08

What is the term for the ratio of the actual speed at which a signal travels through a transmission line to the speed of light in a vacuum?

Select	Answer
A	Standing wave ratio
B	Velocity factor
C	Surge impedance
D	Characteristic impedance

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radio propagation
B	Radiation resistance
C	Impedance along transmission lines
D	Antenna radiation pattern

49. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	Atmospheric noise is so high that gain over a dipole is not important
B	They must be erected at least 1/2 wavelength above the ground to attain good directivity
C	Low loss coax transmission line is essential for good performance
D	All of these choices are correct

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

Select	Answer
A	The extremely high frequency energy can damage the joints of antenna structures
B	Microwaves often travel long distances by ionospheric reflection
C	Microwaves are ionizing radiation
D	The high gain antennas commonly used can result in high exposure levels

Figure E6-5

Figure E9-2