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

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1. - E1A06

Where must the carrier frequency of a CW signal be set to comply with FCC rules for 60 meter operation?

Select	Answer
A	At the highest frequency of the channel
B	At the lowest frequency of the channel
C	On any frequency where the signal's sidebands are within the channel
D	At the center frequency of the channel

2. - E1B05

What is the National Radio Quiet Zone?

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

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

4. - E1D09

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

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

5. - E1E04

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

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

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	10 W
D	1.5 W

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's uplink and downlink frequency bands
B	The type of signals that can be relayed through the satellite
C	The satellite's orientation with respect to the Earth
D	Whether the satellite is in a polar or equatorial orbit

8. - E2B14

What aspect of an amateur slow-scan television signal encodes the brightness of the picture?

Select	Answer
A	Sync amplitude
B	Sync frequency
C	Tone frequency
D	Tone amplitude

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	A 2 meter VHF transceiver with a 1200 baud modem
B	An optical cable connection between the USB ports of 2 separate computers
C	A 440 MHz transceiver with a 9600 baud modem
D	A standard wireless router running custom software

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	It supplies signals to guide the antenna to track the Moon
B	All of these choices are correct
C	It can decode signals many dB below the noise floor using FEC
D	It controls the receiver to track Doppler shift

11. - E2E02

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

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

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is at perigee
B	When the Moon is at apogee
C	When the MUF is above 30 MHz
D	When the Moon is full

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Late at night
B	Noon
C	Morning
D	Afternoon or early evening

14. - E3C10

What does the 304A solar parameter measure?

Select	Answer
A	The solar emission at 304 GHz, correlated to X-Ray flare levels
B	The solar wind velocity at 304 degrees from the solar equator, correlated to solar activity
C	The ratio of X-Ray flux to radio flux, correlated to sunspot number
D	UV emissions at 304 angstroms, correlated to solar flux index

15. - E4A14

What is the purpose of the prescaler function on a frequency counter?

Select	Answer
A	It amplifies low level signals for more accurate counting
B	It divides a higher frequency signal so a low-frequency counter can display the input frequency
C	It prevents oscillation in a low-frequency counter circuit
D	It multiplies a higher frequency signal so a low-frequency counter can display the operating frequency

16. - E4B05

If a frequency counter with a specified accuracy of +/- 10 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1465.20 Hz
B	10 Hz
C	146.52 Hz
D	146.52 kHz

17. - E4C07

What does the MDS of a receiver represent?

Select	Answer
A	The minimum discernible signal
B	The multiplex distortion stability
C	The meter display sensitivity
D	The maximum detectable spectrum

18. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
B	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
C	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
D	When the signals from the transmitters are reflected in phase from airplanes passing overhead

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

20. - E5A10

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

Select	Answer
A	Resistance divided by the reactance of either the inductance or 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	Reactance of the inductance times the reactance of the capacitance

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	55 seconds
C	440 seconds
D	110 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 8
B	Point 3
C	Point 5
D	Point 1

23. - E5D03

What is microstrip?

Select	Answer
A	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
B	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
C	Miniature coax used for low power applications
D	Lightweight transmission line made of common zip cord

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 breakdown voltage of the base to collector junction
C	The frequency at which the current gain is reduced to 1
D	The switching speed of the transistor

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As a constant voltage source
B	As an RF switch
C	As a constant current source
D	As a high voltage rectifier

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	More efficient arithmetic operations
B	High speed operation
C	Low power consumption
D	Ability to connect many device outputs to a common bus

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	Cobalt and aluminum
D	Polystyrene and polyethylene

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	DIP
C	Ball grid array
D	PLCC

29. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It stays the same
B	It decreases
C	It becomes unstable
D	It increases

30. - E7A12

What type of logic defines "0" as a high voltage?

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

31. - E7B02

What is a Class D amplifier?

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

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Omega
B	Cascode
C	Pi
D	Pi-L

33. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Matching of day and night charge rates
B	Prevention of battery undercharge
C	Control of electrolyte levels during battery discharge
D	Prevention of battery damage due to overcharge

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the oscillator
B	A reactance modulator on the oscillator
C	A reactance modulator on the final amplifier
D	A balanced modulator on the audio amplifier

35. - E7F04

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

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

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

Select	Answer
A	100 ohms
B	Very high
C	1000 ohms
D	Very low

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	Bias the crystal at a specified voltage
C	Provide the crystal with a specified parallel capacitance
D	Provide the crystal with a specified parallel inductance

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	256 divided by the gain of the input amplifier
B	8 multiplied by the gain of the input amplifier
C	8
D	256

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the highest audio modulating frequency to the average audio modulating frequency
B	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
C	The ratio of the carrier center frequency to the audio modulating frequency
D	The ratio of the audio modulating frequency to the center carrier frequency

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Binary Coded Decimal Code
B	Gray code
C	Excess 3 code
D	Extended Binary Coded Decimal Interchange Code

41. - E8D04

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

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

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	2000 watts
B	317 watts
C	300 watts
D	126 watts

43. - E9B08

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

Select	Answer
A	Draw two imaginary lines through the ends of the elements and measure the angle between the lines
B	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
C	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear 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. - E9C12

Which of the following describes an extended double Zepp antenna?

Select	Answer
A	An end fed folded dipole antenna
B	A center fed 1.25 wavelength antenna (two 5/8 wave elements in phase)
C	A wideband vertical antenna constructed from precisely tapered aluminum tubing
D	A portable antenna erected using two push support poles

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	Near the center of the vertical radiator
B	As low as possible on the vertical radiator
C	At a voltage node
D	As close to the transmitter as possible

46. - E9E07

What term best describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Dielectric constant
B	Reflection coefficient
C	Characteristic impedance
D	Velocity factor

47. - E9F07

How does ladder line compare to small-diameter coaxial cable such as RG-58 at 50 MHz?

Select	Answer
A	Lower velocity factor
B	Smaller reflection coefficient
C	Higher SWR
D	Lower loss

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	Impedance axis
B	Polar axis
C	Prime axis
D	Reactance axis

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By reducing the permeability of the loop shield
B	By increasing either the number of wire turns in the loop or the area of the loop structure or both
C	By increasing the number of wire turns in the loop and reducing the area of the loop structure
D	By winding adjacent turns in opposing directions

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Uranium Hexafluoride
B	Zinc oxide
C	Mica
D	Beryllium Oxide

Figure E5-2

Figure E9-3