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	17 meter band
C	60 meter band
D	30 meter band

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

3. - E1C13

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

Select	Answer
A	You must identify in the official language of the country in which you are operating
B	You must append "/CEPT" to your call sign
C	You must bring a copy of FCC Public Notice DA 11-221
D	The U.S. embassy must approve of your operation

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
B	A radio communications service using stations on Earth satellites for public service broadcast
C	A radio communications service using amateur radio stations on satellites
D	A spacecraft launching service for amateur-built satellites

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The prospective VE obtains accreditation from the FCC
B	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
C	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
D	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

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

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From east to west
B	From west to east
C	From south to north
D	From north to south

8. - E2B18

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

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

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 440 MHz transceiver with a 9600 baud modem
B	An optical cable connection between the USB ports of 2 separate computers
C	A 2 meter VHF transceiver with a 1200 baud modem
D	A standard wireless router running custom software

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	All of these choices are correct
B	15 second timed transmission sequences with stations alternating based on location
C	Use of high speed CW or digital modes
D	Short transmission with rapidly repeated call signs and signal reports

11. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	PACTOR
B	AMTOR
C	Hellschreiber
D	RTTY

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of two electric fields at parallel right angles to each other
B	A wave of alternating current, in the core of an electromagnet
C	A wave consisting of two magnetic fields at right angles to each other
D	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other

13. - E3B07

Which of the following could account for hearing an echo on the received signal of a distant station?

Select	Answer
A	High D layer absorption
B	Receipt of a signal by more than one path
C	Transmit frequency is higher than the MUF
D	Meteor scatter

14. - E3C15

What might a sudden rise in radio background noise indicate?

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

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	Analog-to-digital conversion speed of the soundcard
C	Amount of memory on the soundcard
D	All of these choices are correct

16. - E4B11

How should an antenna analyzer be connected when measuring antenna resonance and feed point impedance?

Select	Answer
A	Connect the antenna feed line directly to the analyzer's connector
B	Connect the analyzer via a high-impedance transformer to the antenna
C	Loosely couple the analyzer near the antenna base
D	Loosely couple the antenna and a dummy load to the analyzer

17. - E4C11

Which of the following is a desirable amount of selectivity for an amateur SSB phone receiver?

Select	Answer
A	4.8 kHz
B	4.2 kHz
C	2.4 kHz
D	1 kHz

18. - E4D01

What is meant by the blocking dynamic range of a receiver?

Select	Answer
A	The minimum difference in dB between two signals which produce third order intermodulation products greater than the noise floor
B	The difference in dB between the noise floor and the third order intercept point
C	The minimum difference in dB between the levels of two FM signals which will cause one signal to block the other
D	The difference in dB between the noise floor and the level of an incoming signal which will cause 1 dB of gain compression

19. - E4E05

How can noise from an electric motor be suppressed?

Select	Answer
A	By installing a brute-force AC-line filter in series with the motor leads
B	By installing a bypass capacitor in series with the motor leads
C	By installing a high pass filter in series with the motor's power leads
D	By using a ground-fault current interrupter in the circuit used to power the motor

20. - E5A14

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

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

21. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

Select	Answer
A	One time constant
B	One exponential period
C	An exponential rate of one
D	A time factor of one

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 5
B	Point 8
C	Point 3
D	Point 1

23. - E5D09

What happens to reactive power in an AC circuit that has both ideal inductors and ideal capacitors?

Select	Answer
A	It is repeatedly exchanged between the associated magnetic and electric fields, but is not dissipated
B	It is dissipated as heat in the circuit
C	It is dissipated in the formation of inductive and capacitive fields
D	It is dissipated as kinetic energy in the circuit

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	4
C	2
D	6

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Silicon-controlled rectifier
B	Varactor diode
C	Zener diode
D	Tunnel diode

26. - E6C13

Which of the following is an advantage of BiCMOS logic?

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

27. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance
B	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
C	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
D	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	50 ohms
B	10 ohms
C	300 ohms
D	450 ohms

29. - 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 device that uses semiconductors to implement the functions of an electromechanical relay
C	A relay using transistors to drive the relay coil
D	A passive delay line

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It produces logic "1" at its output if any or all inputs are logic "1"
B	It produces logic "0" at its output if all inputs are logic "1"
C	It only produces logic "0" at its output when all inputs are logic "1"
D	It produces logic "1" at its output if all inputs are logic "0"

31. - E7B10

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

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

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Greater harmonic suppression
B	Greater transformation range
C	Higher efficiency
D	Lower losses

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

Select	Answer
A	It is generally less efficient than a linear regulator
B	It gives a ramp voltage at its output
C	The resistance of a control element is varied in direct proportion to the line voltage or load current
D	The controlled device's duty cycle is changed to produce a constant average output voltage

34. - E7E10

How does a diode detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By mixing signals with noise in the transition region of the diode
C	By breakdown of the Zener voltage
D	By sensing the change of reactance in the diode with respect to frequency

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	4 bits
B	6 bits
C	8 bits
D	10 bits

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	0.21
B	47
C	24
D	94

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a tapped coil
C	Through link coupling
D	Through a quartz crystal

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Lower the input bandwidth to increase the effective resolution
B	Remove harmonics from the output caused by the discrete analog levels generated
C	All of these choices are correct
D	Improve accuracy by removing out of sequence codes from the input

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	0.3
B	3
C	1000
D	3000

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By transmitting extra data that may be used to detect and correct transmission errors
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By varying the frequency shift of the transmitted signal according to a predefined algorithm
D	By the receiving station repeating each block of three data characters

41. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Low-pass filters at the transmitter output
B	Reduce keying waveform rise and fall times
C	Increase keying waveform rise and fall times
D	High-pass filters at the transmitter output

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	The standing wave ratio
B	Take-off angle
C	Soil conductivity
D	Distance from the transmitter

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	7
B	4
C	1
D	3

44. - E9C13

What is the main effect of placing a vertical antenna over an imperfect ground?

Select	Answer
A	It changes the impedance angle of the matching network
B	It reduces losses in the radiating portion of the antenna
C	It causes increased SWR
D	It reduces low-angle radiation

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To cancel capacitive reactance
B	To increase the SWR bandwidth
C	To lower the losses
D	To lower the Q

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To provide a rejection notch that prevents the radiation of harmonics
B	To transform the antenna impedance to a higher value
C	To provide DC isolation between the feed line and the antenna
D	To cancel the inductive reactance of the matching network

47. - E9F05

What is the approximate physical length of a solid polyethylene dielectric coaxial transmission line that is electrically one-quarter wavelength long at 14.1 MHz?

Select	Answer
A	3.5 meters
B	0.2 meters
C	2.3 meters
D	20 meters

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning impedance values with regard to the prime center
B	Reassigning prime center with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning resistance values with regard to the reactance axis

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing the number of wire turns in the loop and reducing the area of the loop structure
B	By reducing the permeability of the loop shield
C	By winding adjacent turns in opposing directions
D	By increasing either the number of wire turns in the loop or the area of the loop structure or both

50. - E0A05

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

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

Figure E5-2

Figure E6-2

Figure E7-1

Figure E7-4

Figure E9-2