US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A05

What is one of the potential hazards of operating in the amateur radio microwave 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	The high gain antennas commonly used can result in high exposure levels
D	Microwaves are ionizing radiation

2. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the highest frequency of the channel
B	At the center frequency of the channel
C	At the lowest frequency of the channel
D	On any frequency where the signal's sidebands are within the channel

3. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
B	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
C	Any FCC-licensed amateur station except a Technician Class
D	Only those club stations licensed to Amateur Extra Class operators

4. - E1C06

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	The U.S. embassy must approve of your operation
B	You must identify in the official language of the country in which you are operating
C	You must bring a copy of FCC Public Notice DA 16-1048
D	You must append "/CEPT" to your call sign

5. - E1D07

Which HF amateur bands have frequencies authorized for space stations?

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

6. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The FCC
B	The VEC coordinating the session
C	Each administering VE
D	The VE session manager

7. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and south of the border between the U.S. and Canada
B	A line roughly parallel to and north of the border between the U.S. and Mexico
C	A line roughly parallel to and east of the U.S. Pacific coastline
D	A line roughly parallel to and west of the U.S. Atlantic coastline

8. - E2A12

What is the purpose of digital store-and-forward functions on an amateur radio satellite?

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

9. - E2B05

Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?

Select	Answer
A	Vestigial sideband provides high frequency emphasis to sharpen the picture
B	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
C	The vestigial sideband contains chroma information
D	The vestigial sideband carries the audio information

10. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	2 meters
B	6 meters
C	33 centimeters
D	30 meters

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event
B	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
C	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
D	All these choices are correct

12. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK occupies less bandwidth
B	Only direct FSK can be decoded by computer
C	Direct FSK can transmit faster baud rates
D	Direct FSK applies the data signal to the transmitter VFO, while AFSK transmits tones via phone

13. - E3A05

Tropospheric propagation of microwave signals often occurs in association with what phenomenon?

Select	Answer
A	Warm and cold fronts
B	Grayline
C	Sprites and jets
D	Lightning discharges

14. - E3B05

Which amateur bands typically support long-path propagation?

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

15. - E3C06

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

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

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and time
B	RF amplitude and frequency
C	SWR and time
D	SWR and frequency

17. - E4B11

Which of the following can be measured with a vector network analyzer?

Select	Answer
A	Input impedance
B	Output impedance
C	All these choices are correct
D	Reflection coefficient

18. - E4C02

Which of the following receiver circuits can be effective in eliminating interference from strong out-of-band signals?

Select	Answer
A	A front-end filter or pre-selector
B	A notch filter
C	A narrow IF filter
D	A properly adjusted product detector

19. - E4D07

Which of the following reduces the likelihood of receiver desensitization?

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

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

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

21. - E5A14

What is the resonant frequency of an RLC circuit if R is 22 ohms, L is 50 microhenries and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	1.78 MHz
C	22.36 MHz
D	44.72 MHz

22. - E5B02

What letter is commonly used to represent susceptance?

Select	Answer
A	B
B	X
C	Y
D	G

23. - E5C11

Which point in Figure E5-1 best represents the impedance of a series circuit consisting of a 300-ohm resistor and an 18-microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 1
B	Point 8
C	Point 3
D	Point 7

24. - E5D08

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	1600 watts
B	200 watts
C	1000 watts
D	600 watts

25. - E6A05

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has lower input impedance
B	An FET has higher input impedance
C	They are both high impedance
D	They are both low impedance

26. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch?

Select	Answer
A	Ability to dissipate large amounts of power
B	Reverse bias controls its forward voltage drop
C	Low junction capacitance
D	Extremely high reverse breakdown voltage

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	1
B	3
C	4
D	2

28. - 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	Butterworth filters
B	Electrolytic capacitors
C	Ferrite beads
D	Steel-core toroids

29. - E6E05

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

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

30. - E6F07

What is a solid-state relay?

Select	Answer
A	A mechanical relay that latches in the on or off state each time it is pulsed
B	A semiconductor passive delay line
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A relay using transistors to drive the relay coil

31. - E7A11

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

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

32. - E7B13

Which of the following describes an emitter follower (or common collector) amplifier?

Select	Answer
A	A differential amplifier with both inputs fed to the emitter of the input transistor
B	An amplifier with a low impedance output that follows the base input voltage
C	A two-transistor amplifier with the emitters sharing a common bias resistor
D	An OR circuit with only one emitter used for output

33. - E7C12

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	L-networks cannot perform impedance transformation
B	Pi-networks are more stable
C	Pi-networks provide balanced input and output
D	The Q of Pi-networks can be controlled

34. - E7D11

What is the function of the pass transistor in a linear voltage regulator circuit?

Select	Answer
A	Maintains nearly constant output impedance over a wide range of load current
B	Provides a stable input impedance over a wide range of source voltage
C	Permits a wide range of output voltage settings
D	Maintains nearly constant output voltage over a wide range of load current

35. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A heterodyne enhancer
B	A de-emphasis network
C	A heterodyne suppressor
D	A pre-emphasis network

36. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	Select the point at which baseband signals are generated
B	Provide access for debugging software
C	Provide incremental signal delays for filter algorithms
D	To reduce excess signal pressure levels

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 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	0.23 volts
C	-0.23 volts
D	2.3 volts

38. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A diode-switching matrix synthesizer
B	A direct digital synthesizer
C	A hybrid synthesizer
D	A phase-locked loop synthesizer

39. - E8A07

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

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

40. - 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	0.47
B	0.214
C	2.14
D	47

41. - E8C12

What factors affect the bandwidth of a transmitted CW signal?

Select	Answer
A	IF bandwidth and Q
B	All these choices are correct
C	Modulation index and output power
D	Keying speed and shape factor (rise and fall time)

42. - E8D11

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

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

43. - E9A05

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

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

44. - E9B10

What is the principle of a Method of Moments analysis?

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

45. - E9C05

Which of the following is a type of OCFD antenna?

Select	Answer
A	A multiband dipole antenna using one-way circular polarization for frequency diversity
B	A dipole fed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
C	A folded dipole center-fed with 300-ohm transmission line
D	A remotely tunable dipole antenna using orthogonally controlled frequency diversity

46. - 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

47. - E9E01

What system matches a higher-impedance transmission line to a lower-impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The delta matching system
B	The omega matching system
C	The gamma matching system
D	The stub matching system

48. - E9F03

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

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

49. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and reactance
B	Voltage and impedance
C	Reactance and voltage
D	Resistance and voltage

50. - 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

Figure E5-1

Figure E6-3

Figure E7-3