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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Discontinue forwarding the communication as soon as you become aware of it
B	Notify the nearest FCC Field Engineer's office
C	Discontinue forwarding all messages
D	Notify the originating station that the communication does not comply with FCC rules

2. - E1B07

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

Select	Answer
A	0.5
B	1.0
C	3.0
D	2.0

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When agreed upon by the sending or receiving station
B	When approved by the National Telecommunication and Information Administration
C	Never
D	Only when transmitting RTTY or data emissions

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

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

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 all the VECs
C	In a question pool maintained by the FCC
D	In the appropriate FCC Report and Order

6. - E1F09

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

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

7. - E2A13

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	HEO
B	Geostationary
C	Geomagnetic
D	LEO

8. - E2B19

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

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

9. - E2C01

Which of the following is true about contest operating?

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

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

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

11. - E2E03

How is the timing of JT65 contacts organized?

Select	Answer
A	It depends on the lunar phase
B	Alternating transmissions at 1 minute intervals
C	By exchanging ACK/NAK packets
D	Stations take turns on alternate days

12. - E3A16

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

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

13. - E3B11

At what time of day is Sporadic-E propagation most likely to occur?

Select	Answer
A	Any time
B	Early evening
C	Around sunrise
D	Around sunset

14. - E3C02

What is indicated by a rising A or K index?

Select	Answer
A	Higher levels of solar UV radiation
B	An increase in the critical frequency
C	Increasing disruption of the geomagnetic field
D	Decreasing disruption of the geomagnetic field

15. - E4A01

Which of the following parameter determines the bandwidth of a digital or computer-based oscilloscope?

Select	Answer
A	Input impedance
B	Input capacitance
C	Sampling rate
D	Sample resolution

16. - E4B11

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

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

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio of thermal noise to atmospheric noise
B	The ratio of atmospheric noise to phase noise
C	The ratio of the noise bandwidth in Hertz to the theoretical bandwidth of a resistive network
D	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Neutralization
B	Adjacent channel interference
C	Amplifier desensitization
D	Intermodulation interference

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	A malfunctioning illuminated advertising display
B	A defective doorbell or doorbell transformer inside a nearby residence
C	Arcing contacts in a thermostatically controlled device
D	All of these choices are correct

20. - E5A10

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

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

21. - E5B03

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

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

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

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

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By dividing the reactive power by the power factor
B	By dividing the apparent power by the power factor
C	By multiplying the reactive power times the power factor
D	By multiplying the apparent power times the power factor

24. - E6A15

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

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

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Enhanced carrier retention time
B	Much higher reverse voltage breakdown
C	Less forward voltage drop
D	Controlled reverse avalanche voltage

26. - E6C14

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

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

27. - E6D16

What is the common name for a capacitor connected across a transformer secondary that is used to absorb transient voltage spikes?

Select	Answer
A	Clipper capacitor
B	Trimmer capacitor
C	Snubber capacitor
D	Feedback capacitor

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Surface mount
B	Stripped lead
C	Virtual lead mounting
D	Direct soldering

29. - E6F11

What is the approximate open-circuit voltage produced by a fully-illuminated silicon photovoltaic cell?

Select	Answer
A	0.1 V
B	12 V
C	0.5 V
D	1.5 V

30. - E7A11

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

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

31. - E7B07

Which of the following is a likely result when a Class C amplifier is used to amplify a single-sideband phone signal?

Select	Answer
A	Signal distortion and excessive bandwidth
B	Signal inversion
C	Reduced intermodulation products
D	Increased overall intelligibility

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	An active LC filter
B	A Butterworth filter
C	A Chebyshev filter
D	A passive op-amp filter

33. - E7D05

Which of the following types of linear voltage regulator places a constant load on the unregulated voltage source?

Select	Answer
A	A shunt current source
B	A shunt regulator
C	A constant current source
D	A series regulator

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce AM signals by using an electrically variable inductance or capacitance
B	To produce AM signals by using an electrically variable resistance
C	To produce PM signals by using an electrically variable inductance or capacitance
D	To produce PM signals by using an electrically variable resistance

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	An adaptive filter
B	A Hilbert-transform filter
C	A phase-inverting filter
D	A crystal-lattice filter

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	14
C	28
D	7

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Pierce and Zener
B	Negative feedback and balanced feedback
C	Armstrong and deForest
D	Colpitts and Hartley

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Less complex circuitry is required for digital signal generation and detection
B	Digital signals always occupy a narrower bandwidth
C	All of these choices are correct
D	Digital signals can be regenerated multiple times without error

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A bandwidth compression technique using Fourier transforms
B	A frequency modulation technique which uses non-harmonically related frequencies
C	A digital mode for narrow band, slow speed transmissions
D	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

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	Binary Coded Decimal Code
C	Excess 3 code
D	Gray code

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear
B	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
C	A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
D	If interference is detected by the receiver it will signal the transmitter to change frequencies

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(radiation resistance / total resistance) x 100 per cent
B	(total resistance / radiation resistance) x 100 per cent
C	(radiation resistance / transmission resistance) x 100 per cent
D	(effective radiated power / transmitter output) x 100 percent

43. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a series of segments, each having a uniform value of current
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 points, each having a distinct location in space
D	A wire is modeled as a single sine-wave current generator

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

Select	Answer
A	A Figure-8 end-fire along the axis of the array
B	Cardioid
C	A Figure-8 broadside to the axis of the array
D	Omni-directional

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance increases and the capacitive reactance increases
B	The radiation resistance decreases and the capacitive reactance increases
C	The radiation resistance increases and the capacitive reactance decreases
D	The radiation resistance decreases and the capacitive reactance decreases

46. - E9E08

Which of the following measurements is characteristic of a mismatched transmission line?

Select	Answer
A	A dielectric constant greater than 1
B	An SWR less than 1:1
C	A reflection coefficient greater than 1
D	An SWR greater than 1:1

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	71 meters
B	10 meters
C	20 meters
D	15 meters

48. - E9G07

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

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

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It allows stations to communicate without giving away their position
B	It automatically cancels ignition noise in mobile installations
C	It is electro statically balanced against ground, giving better nulls
D	It eliminates tracking errors caused by strong out-of-band signals

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Make sure signals from your station are less than the controlled MPE limits
B	Make sure signals from your station are less than the uncontrolled MPE limits
C	You need only evaluate exposure levels on your own property
D	Advise your neighbors of the results of your tests

Figure E5-2

Figure E7-4

Figure E9-3