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

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	3.0
B	2.0
C	0.5
D	1.0

3. - E1C02

What is meant by automatic control of a station?

Select	Answer
A	The use of a control link between a control point and a locally controlled station
B	The use of devices and procedures for control so that the control operator does not have to be present at a control point
C	A station operating with its output power controlled automatically
D	Remotely controlling a station's antenna pattern through a directional control link

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Only those of Amateur Extra Class operators
B	Only those of General, Advanced or Amateur Extra Class operators
C	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
D	Any amateur station, subject to the privileges of the class of operator license held by the control operator

5. - E1E05

What is the minimum passing score on amateur operator license examinations?

Select	Answer
A	Minimum passing score of 74%
B	Minimum passing score of 77%
C	Minimum passing score of 80%
D	Minimum passing score of 70%

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	420 MHz - 430 MHz
C	53 MHz - 54 MHz
D	440 MHz - 450 MHz

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of ionospheric absorption
B	Because the satellite is spinning
C	Because of the satellite's low orbital altitude
D	Because of the Doppler Effect

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	60
B	525
C	1080
D	30

9. - E2C08

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

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

10. - E2D07

What digital protocol is used by APRS?

Select	Answer
A	802.11
B	AMTOR
C	AX.25
D	PACTOR

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Audio FSK can be performed anywhere in the transmit chain
B	Direct FSK applies the data signal to the transmitter VFO
C	Direct FSK uses a DC-coupled data connection
D	Audio FSK has a superior frequency response

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

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

Select	Answer
A	5000 miles
B	1000 miles
C	2500 miles
D	7500 miles

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 four times the distance
D	By approximately twice the distance

15. - E4A08

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

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

16. - E4B09

What is indicated if the current reading on an RF ammeter placed in series with the antenna feed line of a transmitter increases as the transmitter is tuned to resonance?

Select	Answer
A	There is possibly a short to ground in the feed line
B	There is an impedance mismatch between the antenna and feed line
C	The transmitter is not properly neutralized
D	There is more power going into the antenna

17. - E4C06

A CW receiver with the AGC off has an equivalent input noise power density of -174 dBm/Hz. What would be the level of an unmodulated carrier input to this receiver that would yield an audio output SNR of 0 dB in a 400 Hz noise bandwidth?

Select	Answer
A	-155 dBm
B	-174 dBm
C	-164 dBm
D	-148 dBm

18. - E4D11

Why are third-order intermodulation products created within a receiver of particular interest compared to other products?

Select	Answer
A	Third-order products are an indication of poor image rejection
B	The third-order intercept is much higher than other orders
C	Third-order intermodulation produces three products for every input signal within the band of interest
D	The third-order product of two signals which are in the band of interest is also likely to be within the band

19. - E4E11

Which is the most likely cause if you are hearing combinations of local AM broadcast signals within one or more of the MF or HF ham bands?

Select	Answer
A	Nearby corroded metal joints are mixing and re-radiating the broadcast signals
B	You are receiving sky wave signals from a distant station
C	The broadcast station is transmitting an over-modulated signal
D	Your station receiver IF amplifier stage is defective

20. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	L/R
B	Minimum
C	Maximum
D	R/L

21. - E5B03

What happens to the phase angle of a reactance when it is converted to a susceptance?

Select	Answer
A	It is unchanged
B	The susceptance phase angle is the inverse of the reactance phase angle
C	The sign is reversed
D	It is shifted by 90 degrees

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	Resistive component
B	The difference between the resistive and reactive components
C	The sum of the reactive and resistive components
D	Reactive component

23. - E5D06

In what direction is the magnetic field oriented about a conductor in relation to the direction of electron flow?

Select	Answer
A	In a direction opposite to the current
B	In all directions; omni-directional
C	In a direction determined by the left-hand rule
D	In the same direction as the current

24. - E6A03

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

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

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	An internal capacitance that varies with the applied voltage
B	A constant current drop under conditions of varying voltage
C	A constant voltage drop under conditions of varying current
D	A negative resistance region

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	Programmable equipment used for testing digital logic integrated circuits
B	An algorithm for simulating logic functions during circuit design
C	A programmable collection of logic gates and circuits in a single integrated circuit
D	A device to control industrial equipment

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	RF susceptance would increase
B	Magnetic flux would increase with frequency
C	Harmonics and distortion could result
D	Temporary changes of the core permeability could result

28. - E6E06

What characteristics of the MMIC make it a popular choice for VHF through microwave circuits?

Select	Answer
A	The ability to retrieve information from a single signal even in the presence of other strong signals
B	Controlled gain, low noise figure, and constant input and output impedance over the specified frequency range
C	Plate current that is controlled by a control grid
D	Nearly infinite gain, very high input impedance, and very low output impedance

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A crystalline semiconductor
B	A liquid semiconductor
C	A heavy metal
D	An ordinary metal

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	Astable multivibrator
B	T flip-flop
C	J-K flip-flop
D	Monostable multivibrator

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

Select	Answer
A	Class C
B	Push-pull
C	Class AB
D	Push-push

32. - E7C09

What is a Jones filter as used as part of an HF receiver IF stage?

Select	Answer
A	A special filter that emphasizes image responses
B	An automatic notch filter
C	A filter that removes impulse noise E7C10 (B) Which of the following filters would be the best choice for use in a 2 meter repeater duplexer? A. A crystal filter B. A cavity filter C. A DSP filter D. An L-C filter
D	A variable bandwidth crystal lattice filter

33. - E7D02

What is one characteristic of a switching electronic voltage regulator?

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

34. - E7E12

What is a frequency discriminator stage in a FM receiver?

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

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	Higher data rate
B	More taps
C	Double-precision math routines
D	Complex phasor representations

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	76
B	38
C	0.03
D	1

37. - E7H05

How is positive feedback supplied in a Pierce oscillator?

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

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A square wave
B	A sine wave
C	A sawtooth wave
D	A cosine wave

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	2000
C	1/3
D	6000

40. - E8C01

How is Forward Error Correction implemented?

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

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	The signal can overpower interfering signals
B	Faster transmission rate
C	Foreign language characters can be sent
D	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth

42. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	9.85 dB
B	14.15 dB
C	12.5 dB
D	6.17 dB

43. - E9B16

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

Select	Answer
A	4
B	3
C	7
D	1

44. - E9C09

What is a G5RV antenna?

Select	Answer
A	A multi-band trap antenna
B	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
C	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a 4:1 balun
D	A phased array antenna consisting of multiple loops

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
B	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
C	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
D	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It is used to feed high-impedance antennas from a low-impedance source
B	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
C	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance
D	It is used to feed low-impedance loads from a high-impedance source

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the characteristic impedance of the line
B	The same as the input impedance to the generator
C	Very high impedance
D	Very low impedance

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Free space radiation directivity chart
B	Elevation angle radiation pattern chart
C	Smith chart
D	Azimuth angle radiation pattern chart

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

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Uranium Hexafluoride
B	Beryllium Oxide
C	Zinc oxide
D	Mica

Figure E7-4

Figure E9-2

Figure E9-3