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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	12 meter band
B	30 meter band
C	60 meter band
D	17 meter band

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Puerto Rico surrounding the Arecibo Radio Telescope
B	An area surrounding the National Radio Astronomy Observatory
C	An area in Florida surrounding Cape Canaveral
D	An area in New Mexico surrounding the White Sands Test Area

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	A station operating with its output power controlled automatically
C	The use of a control link between a control point and a locally controlled station
D	Remotely controlling a station's antenna pattern through a directional control link

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	2 meters
B	6 meters, 2 meters, and 1.25 meters
C	6 meters and 2 meters
D	2 meters and 1.25 meters

5. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
B	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner
C	The prospective VE obtains accreditation from the FCC
D	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By means of the Doppler data for the specified satellite
B	By adding the mean anomaly to the orbital inclination
C	By calculations using the Keplerian elements for the specified satellite
D	By subtracting the mean anomaly from the orbital inclination

8. - E2B07

What is the name of the signal component that carries color information in NTSC video?

Select	Answer
A	Luminance
B	Spectral Intensity
C	Hue
D	Chroma

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Store and forward on the 440 MHz band
B	Multiple Frequency Shift Keying in the 10 GHz band
C	Spread spectrum in the 2.4 GHz band
D	Frequency division multiplex in the 24 GHz band

10. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	An APRS station with a GPS unit can automatically transmit information to show a mobile station's position during the event
C	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
D	All of these choices are correct

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	1200 baud
B	300 baud
C	110 baud
D	48 baud

12. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	1200 miles
B	100 miles to 300 miles
C	2500 miles
D	10 miles to 50 miles

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	Signals travel faster along ionospheric chords
B	Atmospheric noise is lower in the direction of chordal hop propagation
C	The signal experiences less loss along the path compared to normal skip propagation
D	The MUF for chordal hop propagation is much lower than for normal skip propagation

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class X
B	Class B
C	Class A
D	Class M

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Modulation monitor
C	Bit error rate tester
D	Logic analyzer

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	0.1 MHz
B	1.4652 kHz
C	14.652 Hz
D	1.4652 Hz

17. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	The reference voltage of the analog-to-digital converter
B	One-half the maximum sampling buffer size
C	One-half the maximum sample rate
D	The maximum count value of the analog-to-digital converter

18. - E4D06

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

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

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	Nearby signals may appear to be excessively wide even if they meet emission standards
B	Received audio in the speech range might have an echo effect
C	The audio frequency bandwidth of the received signal might be compressed
D	FM signals can no longer be demodulated

20. - E5A03

What is the magnitude of the impedance of a series RLC circuit at resonance?

Select	Answer
A	Approximately equal to capacitive reactance
B	High, as compared to the circuit resistance
C	Approximately equal to inductive reactance
D	Approximately equal to circuit resistance

21. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage lagging the current
B	68.2 degrees with the voltage leading the current
C	14.0 degrees with the voltage leading the current
D	68.2 degrees with the voltage lagging the current

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Faraday grid
B	Rectangular coordinates
C	Elliptical coordinates
D	Maidenhead grid

23. - E5D07

What determines the strength of the magnetic field around a conductor?

Select	Answer
A	The amount of current flowing through the conductor
B	The ratio of the current to the resistance
C	The diameter of the conductor
D	The resistance divided by the current

24. - E6A10

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

Select	Answer
A	2
B	6
C	4
D	5

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	5
B	1
C	7
D	6

26. - E6C14

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

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

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Powdered-iron
B	Ferrite
C	Brass
D	Ceramic

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Ground-plane construction
B	Wave-soldering construction
C	Point-to-point construction
D	Microstrip construction

29. - E6F09

What is the efficiency of a photovoltaic cell?

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

30. - E7A04

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

Select	Answer
A	2
B	1
C	8
D	4

31. - E7B02

What is a Class D amplifier?

Select	Answer
A	An amplifier that uses drift-mode FETs for high efficiency
B	A low power amplifier that uses a differential amplifier for improved linearity
C	A frequency doubling amplifier
D	A type of amplifier that uses switching technology to achieve high efficiency

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

33. - E7D15

What is the purpose of a "step-start" circuit in a high voltage power supply?

Select	Answer
A	To allow the filter capacitors to charge gradually
B	To provide a dual-voltage output for reduced power applications
C	To allow for remote control of the power supply
D	To compensate for variations of the incoming line voltage

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. - E7F04

What is a common method of generating an SSB signal using digital signal processing?

Select	Answer
A	Emulation of quartz crystal filter characteristics
B	Combine signals with a quadrature phase relationship
C	A frequency synthesizer removes the unwanted sidebands
D	Mixing products are converted to voltages and subtracted by adder circuits

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	38
B	1
C	0.03
D	76

37. - E7H12

Which of the following must be done to insure that a crystal oscillator provides the frequency specified by the crystal manufacturer?

Select	Answer
A	Bias the crystal at a specified current
B	Provide the crystal with a specified parallel inductance
C	Bias the crystal at a specified voltage
D	Provide the crystal with a specified parallel capacitance

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	Data
B	All of these choices are correct
C	Video signals
D	Human speech

39. - E8B10

What describes frequency division multiplexing?

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

40. - E8C10

What is an advantage of Gray code in digital communications where symbols are transmitted as multiple bits

Select	Answer
A	It has more resolution than simple binary
B	It facilitates error detection
C	It has more possible states than simple binary
D	It increases security

41. - E8D04

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

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

42. - E9A07

What is meant by antenna gain?

Select	Answer
A	The ratio of the amount of power radiated by an antenna compared to the transmitter output power
B	The ratio of the signal in the forward direction to that in the opposite direction
C	The ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
D	The final amplifier gain minus the transmission line losses

43. - E9B06

What is the elevation angle of peak response in the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	25 degrees
B	7.5 degrees
C	45 degrees
D	75 degrees

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

45. - E9D05

What is a disadvantage of using a multiband trapped antenna?

Select	Answer
A	It might radiate harmonics
B	It is too sharply directional at lower frequencies
C	It must be neutralized
D	It radiates the harmonics and fundamental equally well

46. - E9E06

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

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

47. - E9F04

What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?

Select	Answer
A	0.30
B	0.10
C	0.66
D	2.70

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Radio propagation
B	Antenna radiation pattern
C	Impedance along transmission lines
D	Radiation resistance

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	High-radiation angle
B	A very sharp peak
C	A very sharp single null
D	Broad band response

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

Figure E6-2

Figure E6-3

Figure E7-4

Figure E9-2