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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	The exact upper band edge
B	1 kHz below the upper band edge
C	3 kHz below the upper band edge
D	300 Hz below the upper band edge

2. - E1B02

Which of the following factors might cause the physical location of an amateur station apparatus or antenna structure to be restricted?

Select	Answer
A	The location is of environmental importance or significant in American history, architecture, or culture
B	The location is in an ITU Zone designated for coordination with one or more foreign governments
C	The location is near an area of political conflict
D	The location is of geographical or horticultural importance

3. - E1C02

What is meant by automatic control of a station?

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

4. - E1D09

Which UHF amateur service bands have frequencies available for a space station?

Select	Answer
A	70 cm only
B	70 cm and 13 cm
C	70 cm and 33 cm
D	33 cm and 13 cm

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	Return the application document to the examinee
D	Destroy the application form

6. - E1F12

Who may be the control operator of an auxiliary station?

Select	Answer
A	Any licensed amateur operator
B	Only Technician, General, Advanced or Amateur Extra Class operators
C	Only General, Advanced or Amateur Extra Class operators
D	Only Amateur Extra Class operators

7. - E2A05

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

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

8. - E2B15

What signals SSTV receiving equipment to begin a new picture line?

Select	Answer
A	Elapsed time
B	Specific tone amplitudes
C	A two-tone signal
D	Specific tone frequencies

9. - E2C06

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

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

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	300 baud packet
B	AMTOR
C	PSK31
D	170 Hz shift, 45 baud RTTY

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	PSK31
B	170 Hz shift, 45 baud RTTY
C	300-baud packet
D	MFSK16

12. - E3A07

Atmospheric ducts capable of propagating microwave signals often form over what geographic feature?

Select	Answer
A	Urban areas
B	Bodies of water
C	Forests
D	Mountain ranges

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They become elliptically polarized
B	Their polarization is randomly modified
C	They are bent toward the magnetic poles
D	They become phase-locked

14. - E3C05

What orientation of Bz (B sub z) increases the likelihood that incoming particles from the Sun will cause disturbed conditions?

Select	Answer
A	Westward
B	Eastward
C	Northward
D	Southward

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	Match the antenna to the load
B	Use high quality double shielded coaxial cables to reduce signal losses
C	All of these choices are correct
D	Attenuate the transmitter output going to the spectrum analyzer

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S21
B	S12
C	S11
D	S22

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	-174 dBm
B	-164 dBm
C	-148 dBm
D	-155 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	The third-order product of two signals which are in the band of interest is also likely to be within the band
D	Third-order intermodulation produces three products for every input signal within the band of interest

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Tying all ground connections to a common point resulting in differential mode currents in the shield
B	Low inductance ground connections at both ends of the shield
C	Common mode currents on the shield and conductors
D	Use of braided shielding material

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	218.3 kHz
B	31.4 kHz
C	436.6 kHz
D	15.7 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	One exponential period
B	One time constant
C	An exponential rate of one
D	A time factor of one

22. - E5C14

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 400 ohm resistor and a 38 picofarad capacitor at 14 MHz?

Select	Answer
A	Point 2
B	Point 4
C	Point 6
D	Point 5

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

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	4
B	5
C	6
D	2

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Tunnel
B	Junction
C	Point contact
D	Zener

26. - E6C14

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

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

27. - E6D04

Which materials are commonly used as a slug core in a variable inductor?

Select	Answer
A	Ferrite and brass
B	Teflon and Delrin
C	Polystyrene and polyethylene
D	Cobalt and aluminum

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Surface mount
B	Radial lead
C	TO-220
D	Axial lead

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The relative fraction of light that is converted to current
B	The effective payback period
C	The output RF power divided by the input DC power
D	The open-circuit voltage divided by the short-circuit current under full illumination

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. - 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. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a high-pass filter
B	It is a band-pass filter
C	It is a notch filter
D	It is a low-pass 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 boost the amount of output current
C	To cut down on waste heat generated by the power supply
D	To improve output voltage regulation

34. - E7E08

What are the principal frequencies that appear at the output of a mixer circuit?

Select	Answer
A	1.414 and 0.707 times the input frequency
B	The sum, difference and square root of the input frequencies
C	The two input frequencies along with their sum and difference frequencies
D	Two and four times the original frequency

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	An adaptive filter
B	A notch filter
C	An elliptical filter
D	A Hilbert-transform 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	28
B	14
C	0.07
D	7

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a capacitive divider
C	Through a tapped coil
D	Through link coupling

38. - E8A12

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

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

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Modulation index
B	Percentage of modulation
C	Quieting index
D	FM compressibility

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

Select	Answer
A	Repeat Request Rate (RRR)
B	Baud rate
C	Intermodulation Distortion (IMD)
D	Signal to noise ratio

42. - E9A11

Which of the following factors determines ground losses for a ground-mounted vertical antenna operating in the 3 MHz to 30 MHz range?

Select	Answer
A	Distance from the transmitter
B	Take-off angle
C	Soil conductivity
D	The standing wave ratio

43. - E9B02

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

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

44. - E9C05

What is an OCFD antenna?

Select	Answer
A	A remotely tunable dipole antenna using orthogonally controlled frequency diversity
B	An eight band dipole antenna using octophase filters
C	A dipole feed approximately 1/3 the way from one end with a 4:1 balun to provide multiband operation
D	A multiband dipole antenna using one-way circular polarization for frequency diversity

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 3 dB
B	Gain is multiplied by 0.707
C	Gain increases by 6 dB
D	Gain does not change

46. - E9E02

What is the name of an antenna matching system that matches an unbalanced feed line to an antenna by feeding the driven element both at the center of the element and at a fraction of a wavelength to one side of center?

Select	Answer
A	The stub match
B	The gamma match
C	The delta match
D	The epsilon match

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

48. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	SWR
B	Frequency
C	Points with constant reactance
D	Points with constant resistance

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
B	It compensates for the effects of an isotropic antenna, thereby improving directivity
C	It prevents receiver overload which could make it difficult to determine peaks or nulls
D	It narrows the bandwidth of the received signal to improve signal to noise ratio

50. - E0A08

What does SAR measure?

Select	Answer
A	Synthetic Aperture Ratio of the human body
B	Signal Amplification Rating
C	The rate of RF energy reflected from stationary terrain
D	The rate at which RF energy is absorbed by the body

Figure E5-2

Figure E6-2

Figure E7-1

Figure E7-4

Figure E9-1