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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the band edge
B	Yes, because you were not the station calling CQ
C	Yes, because the displayed frequency is within the 20 meter band
D	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation on all frequencies above 30 MHz
B	The amateur station must cease operation
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	10 minutes
B	3 minutes
C	5 minutes
D	30 seconds

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	All of these choices are correct
B	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
C	Any amateur station designated by NASA
D	Any amateur station so designated by the ITU

5. - E1E12

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

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

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	222 MHz - 223 MHz
B	53 MHz - 54 MHz
C	420 MHz - 430 MHz
D	440 MHz - 450 MHz

7. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	Power limits for uplink and downlink transmissions
B	The location of the ground control station
C	The uplink and downlink frequency ranges
D	The polarization of uplink and downlink signals

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Chroma
B	Spectral Intensity
C	Luminance
D	Hue

9. - E2C04

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

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

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Digipeating
B	Node hopping
C	Multi-satellite relaying
D	Store-and-forward

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	All of these choices are correct
B	Your transmit frequency is incorrect
C	The protocol version you are using is not the supported by the digital station
D	Another station you are unable to hear is using the frequency

12. - E3A14

From the contiguous 48 states, in which approximate direction should an antenna be pointed to take maximum advantage of aurora propagation?

Select	Answer
A	West
B	North
C	East
D	South

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
B	Propagation between two continents by way of ducts along the magnetic equator
C	Propagation between any two points located on the magnetic equator
D	Propagation between two stations at the same latitude

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 twice the distance
D	By approximately four times the distance

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	An ohmmeter
B	An antenna analyzer
C	A Q meter
D	A spectrum analyzer

16. - E4B02

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

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

17. - E4C12

What is an undesirable effect of using too wide a filter bandwidth in the IF section of a receiver?

Select	Answer
A	Filter ringing
B	Thermal-noise distortion
C	Undesired signals may be heard
D	Output-offset overshoot

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To provide a range of AGC time constants
B	To allow selection of the optimum RF amplifier device
C	To store often-used frequencies
D	To increase rejection of unwanted signals

19. - E4E09

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

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

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

Select	Answer
A	7.12 MHz
B	7.12 kHz
C	23.5 MHz
D	23.5 kHz

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

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Faraday grid
B	Maidenhead grid
C	Elliptical coordinates
D	Rectangular coordinates

23. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100-VAC at 4 amperes?

Select	Answer
A	50 watts
B	80 watts
C	400 watts
D	2000 watts

24. - E6A15

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

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

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant voltage source
B	As an RF detector
C	As a constant current source
D	As a high voltage rectifier

26. - E6C14

What is the primary advantage of using a Programmable Gate Array (PGA) in a logic circuit?

Select	Answer
A	A PGA contains its own internal power supply
B	Complex logic functions can be created in a single integrated circuit
C	All of these choices are correct
D	Many similar gates are less expensive than a mixture of gate types

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

Select	Answer
A	Ferrite toroids generally require fewer turns to produce a given inductance value
B	Ferrite toroids are easier to use with surface mount technology
C	Ferrite toroids generally have better temperature stability
D	Ferrite toroids generally have lower initial permeability

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Two chips in each package (Dual In Package)
B	Package mounts in a direct inverted position
C	Low leakage doubly insulated package
D	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

29. - E6F05

Which describes an optical shaft encoder?

Select	Answer
A	A device which measures the strength of a beam of light using analog to digital conversion
B	A digital encryption device often used to encrypt spacecraft control signals
C	A device for generating RTTY signals by means of a rotating light source
D	A device which detects rotation of a control by interrupting a light source with a patterned wheel

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	1
B	2
C	8
D	4

31. - E7B03

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

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

32. - E7C14

Which mode is most affected by non-linear phase response in a receiver IF filter?

Select	Answer
A	Meteor scatter
B	Single-Sideband voice
C	Digital
D	Video

33. - E7D07

What is the purpose of C2 in the circuit shown in Figure E7-3?

Select	Answer
A	It is a brute force filter for the output
B	To self-resonate at the hum frequency
C	It bypasses hum around D1
D	To provide fixed DC bias for Q1

34. - E7E07

What is meant by the term baseband in radio communications?

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

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Missing codes and jitter
B	Reference voltage level and sample width in bits
C	Data storage transfer rate
D	Sample clock phase noise

36. - E7G11

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 3300 ohms and RF is 47 kilohms?

Select	Answer
A	0.07
B	28
C	7
D	14

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Wide-band AF and RF power amplification
B	Photovoltaic conversion, optical coupling
C	Comparison of two digital input signals, digital pulse counter
D	Frequency synthesis, FM demodulation

38. - E8A11

What type of information can be conveyed using digital waveforms?

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

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	3
B	1/3
C	2000
D	6000

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Extended Binary Coded Decimal Interchange Code
B	Gray code
C	Excess 3 code
D	Binary Coded Decimal Code

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	Strong ALC action
B	Harmonics on higher bands
C	High reflected power
D	Rapid signal fading

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Quarter-wave vertical
B	Half-wave dipole
C	Yagi
D	Isotropic antenna

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Radiation resistance
B	Polarization
C	Elevation
D	Azimuth

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The low-angle radiation increases
B	The low-angle radiation decreases
C	The high-angle radiation increases
D	Both the high-angle and low-angle radiation decrease

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

46. - E9E11

What is an effective way of matching a feed line to a VHF or UHF antenna when the impedances of both the antenna and feed line are unknown?

Select	Answer
A	Use the universal stub matching technique
B	Use a 50 ohm 1:1 balun between the antenna and feed line
C	Connect a parallel-resonant LC network across the antenna feed terminals
D	Connect a series-resonant LC network across the antenna feed terminals

47. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically one-half wavelength long at 14.10 MHz?

Select	Answer
A	15 meters
B	10 meters
C	20 meters
D	71 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 resistance values with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning prime center 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 either the number of wire turns in the loop or the area of the loop structure or both
B	By winding adjacent turns in opposing directions
C	By reducing the permeability of the loop shield
D	By increasing the number of wire turns in the loop and reducing the area of the loop structure

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Ingestion of ozone gas from the cooling system
B	Localized heating of the body from RF exposure in excess of the MPE limits
C	Hearing loss caused by high voltage corona discharge
D	Blood clotting from the intense magnetic field

Figure E7-3

Figure E7-4

Figure E9-2