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

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1. - E1A05

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

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

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

3. - E1C09

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

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

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	70 cm and 33 cm
B	33 cm and 13 cm
C	70 cm only
D	70 cm and 13 cm

5. - E1E12

What must the VE team do with the application form if the examinee does not pass the exam?

Select	Answer
A	Return the application document to the examinee
B	Destroy the application form
C	Maintain the application form with the VEC's records
D	Send the application form to the FCC and inform the FCC of the grade

6. - E1F10

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

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

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To avoid reducing the downlink power to all other users
B	To avoid interfering with terrestrial QSOs
C	To prevent the satellite from emitting out-of-band signals
D	To prevent creating errors in the satellite telemetry

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Tone amplitude
B	Sync frequency
C	Sync amplitude
D	Tone frequency

9. - E2C08

Which of the following contacts may be confirmed through the U.S. QSL bureau system?

Select	Answer
A	Special event contacts between stations in the U.S.
B	Contacts using tactical call signs
C	Repeater contacts between U.S. club members
D	Contacts between a U.S. station and a non-U.S. station

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To relay messages between satellites
B	To upload operational software for the transponder
C	To delay download of telemetry between satellites
D	To store digital messages in the satellite for later download by other stations

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	One of the signal filters is saturated
C	The mark and space signal have been inverted
D	The receiver has drifted 5 kHz from the desired receive frequency

12. - E3A16

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

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

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 40 meters
B	30 meters to 10 meters
C	6 meters to 2 meters
D	160 meters to 10 meters

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It decreases
B	It increases
C	It stays the same
D	It peaks at roughly 14 MHz

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Storage of traces for future reference
B	Automatic amplitude and frequency numerical readout
C	Manipulation of time base after trace capture
D	All of these choices are correct

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	165.2 Hz
B	14.652 kHz
C	146.52 Hz
D	1.4652 MHz

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
B	It reduces receiver sensitivity
C	It decreases receiver third-order intermodulation distortion dynamic range
D	It limits the receiver's ability to receive strong signals

18. - E4D08

What causes intermodulation in an electronic circuit?

Select	Answer
A	Positive feedback
B	Nonlinear circuits or devices
C	Too little gain
D	Lack of neutralization

19. - E4E12

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

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

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Capacitance
B	Resonance
C	Conductance
D	Resistance

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

22. - E5C11

What do the two numbers that are used to define a point on a graph using rectangular coordinates represent?

Select	Answer
A	The magnitude and phase of the point
B	The sine and cosine values
C	The tangent and cotangent values
D	The coordinate values along the horizontal and vertical axes

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

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
B	Only N-type semiconductor material can conduct current
C	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
D	Only P-type semiconductor material can conduct current

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	A large region of intrinsic material
C	Extremely high reverse breakdown voltage
D	Ability to dissipate large amounts of power

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

Select	Answer
A	3
B	1
C	2
D	4

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Electrolytic capacitors
B	Steel-core toroids
C	Ferrite beads
D	Butterworth filters

28. - E6E12

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

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

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	A frequency modulated helium-neon laser
B	A lens and a photomultiplier
C	An LED and a phototransistor
D	An amplitude modulated helium-neon laser

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	An "OR" gate
B	An "AND" gate
C	A flip-flop
D	A clock

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	A frequency doubling amplifier
B	A low power amplifier that uses a differential amplifier for improved linearity
C	A type of amplifier that uses switching technology to achieve high efficiency
D	An amplifier that uses drift-mode FETs for high efficiency

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Omega
B	Pi
C	Cascode
D	Pi-L

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Matching of day and night charge rates
B	Prevention of battery damage due to overcharge
C	Control of electrolyte levels during battery discharge
D	Prevention of battery undercharge

34. - E7E07

What is meant by the term baseband in radio communications?

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

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Add 3 to each input value and subtract 4 from each output value
B	Interpolate by a factor of three, then decimate by a factor of four
C	Change the gain by a factor of 3/4
D	Multiply each sample value by a factor of 3/4

36. - E7G01

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

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

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

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

38. - E8A13

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

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

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
B	Two or more signals are quadrature modulated to increase bandwidth efficiency
C	Two or more signals are arranged to share discrete time slots of a data transmission
D	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter

40. - E8C05

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

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

41. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It uses one character as a shift code to send numeric and special characters
B	It is possible to transmit both upper and lower case text
C	It includes built in error correction features
D	It contains fewer information bits per character than any other code

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

Select	Answer
A	Sunspot activity and time of day
B	Transmission-line length
C	The settings of an antenna tuner at the transmitter
D	Antenna height, conductor length/diameter ratio and location of nearby conductive objects

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

44. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
B	An end fed folded dipole antenna
C	A wideband vertical antenna constructed from precisely tapered aluminum tubing
D	A portable antenna erected using two push support poles

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Higher losses
C	Greater structural strength
D	Lower Q

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable
B	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
C	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
D	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Resistance lines and reactance chords
B	Voltage lines and current chords
C	Voltage circles and current arcs
D	Resistance circles and reactance arcs

49. - E9H02

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

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

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Advise your neighbors of the results of your tests
B	Make sure signals from your station are less than the controlled MPE limits
C	You need only evaluate exposure levels on your own property
D	Make sure signals from your station are less than the uncontrolled MPE limits

Figure E6-5