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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	12 meter band
B	60 meter band
C	17 meter band
D	30 meter band

2. - E1B01

Which of the following constitutes a spurious emission?

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

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

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 kW
B	10 W
C	1.5 W
D	1 W

7. - E2A10

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

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

8. - E2B18

On which of the following frequencies is one likely to find FM ATV transmissions?

Select	Answer
A	29.6 MHz
B	1255 MHz
C	52.525 MHz
D	14.230 MHz

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

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Polar coordinates
B	Radio direction finding spectrum analysis
C	Time and frequency
D	Latitude and longitude

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	MFSK16
B	PSK31
C	300-baud packet
D	170 Hz shift, 45 baud RTTY

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Dust devil
B	The jet stream
C	Wind shear
D	Temperature inversion

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	Atmospheric noise is lower in the direction of chordal hop propagation
B	Signals travel faster along ionospheric chords
C	The MUF for chordal hop propagation is much lower than for normal skip propagation
D	The signal experiences less loss along the path compared to normal skip propagation

14. - E3C06

By how much does the VHF/UHF radio horizon distance exceed the geometric horizon?

Select	Answer
A	By approximately 15 percent of the distance
B	By approximately 50 percent of the distance
C	By approximately four times the distance
D	By approximately twice the distance

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

Select	Answer
A	Calibration of the vertical scale is no longer valid
B	False triggering occurs
C	False signals are displayed
D	All signals will have a DC offset

16. - E4B02

What is an advantage of using a bridge circuit to measure impedance?

Select	Answer
A	It is relatively immune to drift in the signal generator source
B	It provides an excellent match under all conditions
C	It can display results directly in Smith chart format
D	It is very precise in obtaining a signal null

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	-174 dBm
B	-155 dBm
C	-164 dBm
D	-148 dBm

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Cross-modulation of the desired signal and desensitization from strong adjacent signals
B	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
C	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
D	Oscillator instability and severe audio distortion of all but the strongest received signals

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

Select	Answer
A	Ringing in the DSP filter will completely remove the spaces between the CW characters
B	Received CW signals will appear to be modulated at the DSP clock frequency
C	A DSP filter can remove the desired signal at the same time as it removes interfering signals
D	Any nearby signal passing through the DSP system will overwhelm the desired signal

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	Minimum
B	R/L
C	L/R
D	Maximum

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage and current are 180 degrees out of phase
B	Voltage leads current by 90 degrees
C	Current leads voltage by 90 degrees
D	Voltage and current are in phase

22. - E5C07

What is a vector?

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

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By multiplying the apparent power times the power factor
B	By dividing the apparent power by the power factor
C	By dividing the reactive power by the power factor
D	By multiplying the reactive power times the power factor

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	P-type
B	Bipolar-type
C	Superconductor-type
D	N-type

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Inductive bias
B	Zero bias
C	Reverse bias
D	Forward bias

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	All of these choices are correct
B	Its simplicity results in much less expensive devices than standard CMOS
C	It is totally immune to electrostatic damage
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores have lower Q characteristics
B	Toroidal cores exhibit greater hysteresis
C	Toroidal cores make it easier to couple the magnetic energy into other components
D	Toroidal cores confine most of the magnetic field within the core material

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	-20 dBm
B	44 dBm
C	2 dB
D	-10 dB

29. - E6F01

What is photoconductivity?

Select	Answer
A	The decreased conductivity of an illuminated semiconductor
B	The conversion of electromotive energy to photon energy
C	The increased conductivity of an illuminated semiconductor
D	The conversion of photon energy to electromotive energy

30. - E7A11

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

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

31. - E7B10

In Figure E7-1, what is the purpose of R1 and R2?

Select	Answer
A	Feedback
B	Fixed bias
C	Self bias
D	Load resistors

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a notch filter
B	It is a low-pass filter
C	It is a high-pass filter
D	It is a band-pass filter

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It provides a constant load for the voltage source
B	It provides D1 with current
C	It provides negative feedback to improve regulation
D	It increases the current-handling capability of the regulator

34. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	Automatic limiting occurs
B	Spurious mixer products are generated
C	A beat frequency is generated
D	Mixer blanking occurs

35. - E7F15

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters can respond faster to impulses
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	All of these choices are correct
D	FIR filters delay all frequency components of the signal by the same amount

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	A reduction in high frequency response
C	Undesired oscillations added to the desired signal
D	An echo caused by a long time delay

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

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	All of these choices are correct
B	Human speech
C	Video signals
D	Data

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	0.214
B	47
C	0.47
D	2.14

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The rate at which the waveform of a transmitted signal changes to convey information
B	The number of control characters in a message packet
C	The duration of each bit in a message sent over the air
D	The number of characters carried per second by the station-to-station link

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

42. - E9A15

What is the effective radiated power relative to a dipole of a repeater station with 150 watts transmitter power output, 2 dB feed line loss, 2.2 dB duplexer loss, and 7 dBd antenna gain?

Select	Answer
A	420 watts
B	286 watts
C	1977 watts
D	78.7 watts

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of points, each having a distinct location in space
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a single sine-wave current generator
D	A wire is modeled as a series of segments, each having a distinct value of voltage across it

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A dipole consisting of one wavelength of wire forming a very thin loop
B	A type of ground-plane antenna
C	A dipole configured to provide forward gain
D	A dipole one-quarter wavelength long

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

46. - E9E08

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

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

47. - E9F14

What impedance does a 1/2 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 line
D	The same as the output impedance of the generator

48. - E9G01

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

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

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It has a bidirectional pattern
B	It is non-rotatable
C	It is practical for use only on VHF bands
D	It receives equally well in all directions

50. - E0A10

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

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

Figure E7-1

Figure E7-3