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

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1. - E1A01

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

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

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	A signal transmitted to prevent its detection by any station other than the intended recipient
D	Any transmitted signal that unintentionally interferes with another licensed radio station

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control there is no control operator
B	Under automatic control the control operator is not required to be present at the control point
C	Under local control a control operator is not required to be present at a control point
D	Under local control there is no control operator

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 changing its orbit whenever such a change is ordered by NASA
C	The space station must cease all transmissions after 5 years
D	The space station must be capable of terminating transmissions by telecommand when directed by the FCC

5. - E1E10

What must the administering VEs do after the administration of a successful examination for an amateur operator license?

Select	Answer
A	They must collect and send the documents to the NCVEC for grading
B	They must collect and submit the documents to the coordinating VEC for grading
C	They must submit the application document to the coordinating VEC according to the coordinating VEC instructions
D	They must collect and send the documents to the FCC according to instructions

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	1.5 kW
C	1.5 W
D	10 W

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	Geostationary
B	LEO
C	Geomagnetic
D	HEO

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
B	They are not permitted above 54 MHz
C	None; they are allowed on all amateur frequencies
D	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type

9. - E2C04

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

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

10. - E2D11

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

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

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. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by Moon bounce?

Select	Answer
A	500 miles, if the Moon is at perigee
B	5000 miles, if the Moon is at perigee
C	2000 miles, if the Moon is at apogee
D	12,000 miles, if the Moon is visible by both stations

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Propagation away from the great circle bearing between stations
B	Signals reflected back toward the transmitting station
C	Propagation across the geomagnetic equator
D	Successive ionospheric reflections without an intermediate reflection from the ground

14. - E3C11

What does VOACAP software model?

Select	Answer
A	VHF radio propagation
B	AC voltage and impedance
C	AC current and impedance
D	HF propagation

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

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

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	Intermodulation distortion occurs
B	Cross modulation occurs
C	Harmonics are generated
D	A less accurate reading results

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

Select	Answer
A	Fewer components in the receiver
B	Improved receiver noise figure
C	Easier for front-end circuitry to eliminate image responses
D	Reduced drift

18. - E4D04

Which of the following may reduce or eliminate intermodulation interference in a repeater caused by another transmitter operating in close proximity?

Select	Answer
A	A Class D final amplifier
B	A properly terminated circulator at the output of the transmitter
C	A Class C final amplifier
D	A band-pass filter in the feed line between the transmitter and receiver

19. - E4E09

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

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

20. - E5A01

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

Select	Answer
A	Resistance
B	Capacitance
C	Resonance
D	Conductance

21. - E5B09

What is the relationship between the current through a capacitor and the voltage across a capacitor?

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

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 4
B	Point 5
C	Point 2
D	Point 6

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 reactive power times the power factor
D	By multiplying the apparent power times the power factor

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	Insulated gate
B	P-type
C	N-type
D	Bipolar

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	5
B	7
C	6
D	1

26. - E6C03

What is tri-state logic?

Select	Answer
A	Logic devices that utilize ternary math
B	Low power logic devices designed to operate at 3 volts
C	Logic devices with 0, 1, and high impedance output states
D	Proprietary logic devices manufactured by Tri-State Devices

27. - E6D04

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

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

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	DIP
C	Ball grid array
D	PLCC

29. - E6F08

Why are optoisolators often used in conjunction with solid state circuits when switching 120VAC?

Select	Answer
A	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
B	Optoisolators eliminate the effects of reflected light in the control circuit
C	Optoisolators provide a low impedance link between a control circuit and a power circuit
D	Optoisolators provide impedance matching between the control circuit and power circuit

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A temperature compensating load resistor to improve linearity
B	A low-pass filter to remove switching signal components
C	A matched load resistor to prevent damage by switching transients
D	A high-pass filter to compensate for low gain at low frequencies

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	An active LC filter
B	A Butterworth filter
C	A Chebyshev filter
D	A passive op-amp filter

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow for remote control of the power supply
B	To compensate for variations of the incoming line voltage
C	To allow the filter capacitors to charge gradually
D	To provide a dual-voltage output for reduced power applications

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F01

What is meant by direct digital conversion as applied to software defined radios?

Select	Answer
A	Incoming RF is digitized by an analog-to-digital converter without being mixed with a local oscillator signal
B	Incoming RF is converted to a control voltage for a voltage controlled oscillator
C	Software is converted from source code to object code during operation of the receiver
D	A switching mixer is used to generate I and Q signals directly from the RF input

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	-2.3 volts
B	2.3 volts
C	0.23 volts
D	-0.23 volts

37. - E7H11

What are the major spectral impurity components of direct digital synthesizers?

Select	Answer
A	Digital conversion noise
B	Spurious signals at discrete frequencies
C	Broadband noise
D	Nyquist limit noise

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The degree of carrier suppression
B	The amplifier gain
C	The characteristics of the modulating signal
D	The frequency of the modulating signal

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	1000
B	0.3
C	3
D	3000

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It has more resolution than simple binary
B	It increases security
C	It facilitates error detection
D	It has more possible states than simple binary

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 contains fewer information bits per character than any other code
D	It includes built in error correction features

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Radiation resistance plus transmission resistance
B	Radiation resistance plus ohmic resistance
C	Radiation resistance plus space impedance
D	Transmission-line resistance plus radiation resistance

43. - E9B03

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

Select	Answer
A	24 dB
B	14 dB
C	18 dB
D	12 dB

44. - E9C10

Which of the following describes a Zepp antenna?

Select	Answer
A	A dipole constructed from zip cord
B	An end fed dipole antenna
C	A vertical array capable of quickly changing the direction of maximum radiation by changing phasing lines
D	An omni-directional antenna commonly used for satellite communications

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth increases
B	Gain is reduced
C	More common-mode current is present on the feed line
D	SWR bandwidth decreases

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Reflection coefficient
B	Velocity factor
C	Dielectric constant
D	Characteristic impedance

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	Electrical signals move more slowly in a coaxial cable than in air
B	Skin effect is less pronounced in the coaxial cable
C	The characteristic impedance is higher in a parallel feed line
D	The surge impedance is higher in a parallel feed line

48. - E9G02

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

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

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

50. - E0A05

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

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

Figure E5-2

Figure E6-3

Figure E7-4

Figure E9-1