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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	2.8 kHz
B	170 Hz
C	1.5 kHz
D	60 Hz

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	Specific segments in the amateur service MF, HF, VHF and UHF bands
B	Specific local government channels
C	All amateur service frequencies authorized to the control operator
D	Military Auxiliary Radio System (MARS) channels

3. - E1C11

Which of the following operating arrangements allows an FCC-licensed U.S. citizen to operate in many European countries, and alien amateurs from many European countries to operate in the U.S.?

Select	Answer
A	IARP agreement
B	CEPT agreement
C	ITU reciprocal license
D	All of these choices are correct

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands

5. - E1E12

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

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

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	It was imported from a manufacturer in another country and was certificated by that country's government
B	The equipment dealer assembled it from a kit
C	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
D	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers

7. - E2A13

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

Select	Answer
A	Geomagnetic
B	LEO
C	Geostationary
D	HEO

8. - E2B18

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

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

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	In the middle of the band, usually 25 kHz above the national calling frequency
B	In the middle of each band, usually on the national calling frequency
C	At the top of each band, usually in a segment reserved for contests
D	In the weak signal segment of the band, with most of the activity near the calling frequency

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

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Fatal Error Correction
B	Final Error Correction
C	First Error Correction
D	Forward Error Correction

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	North
B	South
C	East
D	West

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 10 meters
B	6 meters to 2 meters
C	160 meters to 40 meters
D	30 meters to 10 meters

14. - E3C11

What does VOACAP software model?

Select	Answer
A	VHF radio propagation
B	HF propagation
C	AC voltage and impedance
D	AC current and impedance

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
B	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
C	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
D	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude

16. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	25 watts
B	125 watts
C	75 watts
D	100 watts

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Capture effect
B	Cross-modulation interference
C	Frequency discrimination
D	Desensitization

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 store often-used frequencies
C	To increase rejection of unwanted signals
D	To allow selection of the optimum RF amplifier device

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals which appear across a wide bandwidth
B	Signals which appear at one IF but not another
C	Signals which are constant at all IF levels
D	Signals which have a sharply peaked frequency distribution

20. - E5A02

What is resonance in an electrical circuit?

Select	Answer
A	The frequency at which the reactive impedance equals the resistive impedance
B	The frequency at which the capacitive reactance equals the inductive reactance
C	The highest frequency that will pass current
D	The lowest frequency that will pass current

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	55 seconds
B	220 seconds
C	440 seconds
D	110 seconds

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By X and R values
B	By Y and G values
C	By real and imaginary parts
D	By phase angle and amplitude

23. - E5D11

What is the power factor of an R-L circuit having a 60 degree phase angle between the voltage and the current?

Select	Answer
A	1.73
B	1.414
C	0.5
D	0.866

24. - E6A06

What is the beta of a bipolar junction transistor?

Select	Answer
A	The change in collector current with respect to base current
B	The frequency at which the current gain is reduced to 1
C	The breakdown voltage of the base to collector junction
D	The switching speed of the transistor

25. - E6B08

Which of the following describes a type of semiconductor diode?

Select	Answer
A	CMOS-field effect
B	Metal-semiconductor junction
C	Thermionic emission diode
D	Electrolytic rectifier

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 feedback loop becomes unstable
C	The comparator enters latch-up
D	The comparator changes its output state

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	Feedback capacitor
B	Snubber capacitor
C	Trimmer capacitor
D	Clipper capacitor

28. - E6E06

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

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

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Protons
B	Photons
C	Electrons
D	Holes

30. - E7A08

What logical operation does an OR gate perform?

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

31. - E7B10

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

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

32. - E7C09

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

Select	Answer
A	A variable bandwidth crystal lattice filter
B	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
C	A special filter that emphasizes image responses
D	An automatic notch filter

33. - E7D14

What is one purpose of a "bleeder" resistor in a conventional unregulated power supply?

Select	Answer
A	To balance the low-voltage filament windings
B	To improve output voltage regulation
C	To cut down on waste heat generated by the power supply
D	To boost the amount of output current

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

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. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	0.23 volts
B	2.3 volts
C	-2.3 volts
D	-0.23 volts

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
B	An electronic circuit consisting of a precision push-pull amplifier with a differential input
C	An electronic circuit also known as a monostable multivibrator
D	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

38. - E8A12

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

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

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter
C	Two or more information streams are merged into a baseband, which then modulates the transmitter
D	The transmitted signal jumps from band to band at a predetermined rate

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

Select	Answer
A	It improves carrier suppression
B	It is easier to demodulate with a conventional, non-synchronous detector
C	All of these choices are correct
D	This results in the least possible transmitted bandwidth for the particular mode

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	Rapid signal fading
C	High reflected power
D	Harmonics on higher bands

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
B	The specific impedance of the antenna
C	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
D	The combined losses of the antenna elements and feed line

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	18 dB
B	14 dB
C	36 dB
D	24 dB

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Greater structural strength
B	Higher losses
C	Lower Q
D	Improved radiation efficiency

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	Pi-L-network
D	A series capacitor

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	15 meters
D	20 meters

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Reactance axis
B	Polar axis
C	Prime axis
D	Impedance axis

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It is non-rotatable
B	It is practical for use only on VHF bands
C	It has a bidirectional pattern
D	It receives equally well in all directions

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

Figure E7-1

Figure E7-4

Figure E9-1

Figure E9-3