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. - E1A13

Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?

Select	Answer
A	Any person named in an amateur station license grant or a person holding an unrestricted Radiotelephone Operator Permit
B	Any person holding an FCC issued amateur license or who is authorized for alien reciprocal operation
C	Only a person with an FCC Marine Radio
D	Only a person named in an amateur station license grant

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	10 miles
B	3 miles
C	1 mile
D	30 miles

3. - E1C12

What types of communications may be transmitted to amateur stations in foreign countries?

Select	Answer
A	Communications incidental to the purpose of the amateur service and remarks of a personal nature
B	Messages intended for connection to users of the maritime satellite service
C	Business-related messages for non-profit organizations
D	All of these choices are correct

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must cease all transmissions after 5 years
B	All of these choices are correct
C	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
D	The space station must be capable of terminating transmissions by telecommand when directed by the FCC

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

Select	Answer
A	In FCC Part 97
B	In a question pool maintained by the FCC
C	In a question pool maintained by all the VECs
D	In the appropriate FCC Report and Order

6. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 kW
B	1 W
C	1.5 W
D	10 W

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Radar
B	Bandwidth compressed LORAN
C	APRS
D	Doppler shift of beacon signals

8. - E2B19

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

Select	Answer
A	None; they are allowed on all amateur frequencies
B	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
C	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
D	They are not permitted above 54 MHz

9. - E2C01

Which of the following is true about contest operating?

Select	Answer
A	Interference to other amateurs is unavoidable and therefore acceptable
B	Every contest requires a signal report in the exchange
C	Operators are permitted to make contacts even if they do not submit a log
D	It is mandatory to transmit the call sign of the station being worked as part of every transmission to that station

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. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	Winlink
B	PSK31
C	RTTY
D	MFSK

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	The energy propagates through a medium with a high refractive index
B	Changing electric and magnetic fields propagate the energy
C	The waves are reflected by the ionosphere and return to their source
D	Electric and magnetic fields become aligned as they travel

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances
B	Long path and short path waves
C	Refracted rays and reflected waves
D	Independent waves created in the ionosphere that are elliptically polarized

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It increases
B	It peaks at roughly 14 MHz
C	It decreases
D	It stays the same

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	Keep the signal ground connection of the probe as short as possible
B	Never use a high impedance probe to measure a low impedance circuit
C	Never use a DC-coupled probe to measure an AC circuit
D	All of these choices are correct

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

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It reduces receiver sensitivity
B	It limits the receiver's ability to receive strong signals
C	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
D	It decreases receiver third-order intermodulation distortion dynamic range

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. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

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

20. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of either the inductance or capacitance divided by the resistance
B	Reactance of the inductance multiplied by the reactance of the capacitance
C	Resistance divided by the reactance of either the inductance or capacitance
D	Reactance of either the inductance or capacitance multiplied by the resistance

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	220 seconds
B	110 seconds
C	55 seconds
D	440 seconds

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 3
B	Point 5
C	Point 1
D	Point 8

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	704 W
B	252 W
C	355 W
D	1.42 mW

24. - E6A03

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

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

25. - E6B05

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

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

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The IC input can be damaged
B	The comparator changes its output state
C	The feedback loop becomes unstable
D	The comparator enters latch-up

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	35 turns
B	13 turns
C	79 turns
D	141 turns

28. - E6E11

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of voltage to current when exposed to light
B	The conversion of light to electrical energy
C	The conversion of electrical energy to mechanical energy
D	The tendency of a battery to discharge when used outside

30. - E7A04

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

Select	Answer
A	8
B	2
C	4
D	1

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current
B	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
C	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
D	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current

32. - E7C13

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	Pi-networks have fewer components
B	The Q of Pi-networks can be varied depending on the component values chosen
C	L-networks cannot perform impedance transformation
D	Pi-networks are designed for balanced input and output

33. - E7D12

What is the drop-out voltage of an analog voltage regulator?

Select	Answer
A	Minimum input-to-output voltage required to maintain regulation
B	Minimum input voltage for rated power dissipation
C	Maximum amount that the output voltage may decrease at rated load
D	Maximum amount that the output voltage drops when the input voltage is varied over its specified range

34. - E7E10

How does a diode detector function?

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

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At half the rate of the highest frequency component of the signal
B	At twice the rate of the highest frequency component of the signal
C	At the same rate as the highest frequency component of the signal
D	At four times the rate of the highest frequency component of the signal

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	A reduction in high frequency response
B	Undesired oscillations added to the desired signal
C	An echo caused by a long time delay
D	Partial cancellation of the signal over a range of frequencies

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Using the oscillator only for CW and digital signals
B	Mechanically isolating the oscillator circuitry from its enclosure
C	Use of NP0 capacitors
D	Eliminating noise on the oscillator's power supply

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

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

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	3000
C	0.3
D	3

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	They are the same
B	Baud is only used for RTTY
C	Baud is twice the symbol rate
D	Symbol rate is only used for packet-based modes

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	More difficult to copy
B	The generation of RF harmonics
C	Limits data speed
D	The generation of key clicks

42. - E9A02

What antenna has no gain in any direction?

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

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
B	Draw two imaginary lines through the ends of the elements and measure the angle between the lines
C	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
D	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	50 ohms
B	450 ohms
C	72 ohms
D	300 ohms

45. - E9D04

Why should an HF mobile antenna loading coil have a high ratio of reactance to resistance?

Select	Answer
A	To maximize losses
B	To minimize losses
C	To swamp out harmonics
D	To minimize the Q

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	A shunt inductor
B	Pi-network
C	A series capacitor
D	Pi-L-network

47. - E9F11

What impedance does a 1/8 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	The same as the input impedance of the final generator stage
B	The same as the characteristic impedance of the line
C	A capacitive reactance
D	An inductive reactance

48. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The current axis
B	The reactance axis
C	The resistance axis
D	The voltage axis

49. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It should be one or more wavelengths long
B	It must be mounted more than 1 wavelength above ground
C	It should be configured as a four-sided loop
D	Its overall length must not exceed 1/4 wavelength

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
B	Each transmitter operating with a duty-cycle greater than 50 percent
C	Only commercial transmitters
D	Only the most powerful transmitter

Figure E5-2

Figure E9-3