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	1.5 kHz
B	2.8 kHz
C	60 Hz
D	170 Hz

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 in Florida surrounding Cape Canaveral
C	An area in New Mexico surrounding the White Sands Test Area
D	An area surrounding the National Radio Astronomy Observatory

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a repeater using a portable handheld transceiver
B	Controlling a station through a local auxiliary link
C	Automatically manipulating local station controls
D	Direct manipulation of the transmitter by a control operator

4. - E1D09

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

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

5. - E1E13

Which of these choices is an acceptable method for monitoring the applicants if a VEC opts to conduct an exam session remotely?

Select	Answer
A	Record the exam session on video tape for later review by the VE team
B	Use a real-time video link and the Internet to connect the exam session to the observing VEs
C	Have each applicant sign an affidavit stating that all session rules were followed
D	The exam proctor observes the applicants and reports any violations

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A13

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

Select	Answer
A	LEO
B	HEO
C	Geostationary
D	Geomagnetic

8. - E2B02

How many horizontal lines make up a fast-scan (NTSC) television frame?

Select	Answer
A	30
B	60
C	1080
D	525

9. - E2C13

What indicator is required to be used by U.S.-licensed operators when operating a station via remote control where the transmitter is located in the U.S.?

Select	Answer
A	/ followed by the USPS two letter abbreviation for the state in which the remote station is located
B	The ARRL section of the remote station
C	/R# where # is the district of the remote station
D	No additional indicator is required

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	Forward Error Correction
C	Fatal Error Correction
D	Final 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 apogee
B	When the Moon is at perigee
C	When the Moon is full
D	When the MUF is above 30 MHz

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	10 meters
B	80 meters
C	6 meters
D	20 meters

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	A meteor ping
B	Increased transequatorial propagation likely
C	A solar flare has occurred
D	Long-path propagation is occurring

15. - E4A02

Which of the following parameters would a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and time
B	SWR and frequency
C	RF amplitude and frequency
D	SWR and time

16. - E4B08

Which of the following is a characteristic of a good DC voltmeter?

Select	Answer
A	Low impedance input
B	High impedance input
C	High reluctance input
D	Low reluctance input

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	-148 dBm
B	-155 dBm
C	-164 dBm
D	-174 dBm

18. - E4D03

How can intermodulation interference between two repeaters occur?

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

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. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	44.72 MHz
C	1.78 MHz
D	22.36 MHz

21. - E5B05

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

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

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 5
B	Point 1
C	Point 3
D	Point 8

23. - E5D03

What is microstrip?

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

24. - E6A01

In what application is gallium arsenide used as a semiconductor material in preference to germanium or silicon?

Select	Answer
A	In very low frequency RF circuits
B	In microwave circuits
C	In high-current rectifier circuits
D	In high-power audio circuits

25. - E6B09

What is a common use for point contact diodes?

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

26. - E6C12

What is BiCMOS logic?

Select	Answer
A	A logic family based on bismuth CMOS devices
B	An integrated circuit logic family using both bipolar and CMOS transistors
C	A FET logic family based on bimetallic semiconductors
D	A logic device with two CMOS circuits per package

27. - E6D17

Why should core saturation of a conventional impedance matching transformer be avoided?

Select	Answer
A	RF susceptance would increase
B	Harmonics and distortion could result
C	Temporary changes of the core permeability could result
D	Magnetic flux would increase with frequency

28. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Low leakage doubly insulated package
B	Package mounts in a direct inverted position
C	Two chips in each package (Dual In Package)
D	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

29. - E6F10

What is the most common type of photovoltaic cell used for electrical power generation?

Select	Answer
A	Selenium
B	Silicon
C	Cadmium Sulfide
D	Copper oxide

30. - E7A12

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

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

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	All of these choices are correct
B	Select transistors with high beta
C	Neutralization
D	Use a resistor in series with the emitter

32. - E7C09

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

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

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It provides D1 with current
B	It increases the current-handling capability of the regulator
C	It provides negative feedback to improve regulation
D	It provides a constant load for the voltage source

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
B	The lowest frequency band that the transmitter or receiver covers
C	The frequency components present in the modulating signal
D	The unmodulated bandwidth of the transmitted signal

35. - E7F08

What is the function of decimation with regard to digital filters?

Select	Answer
A	Attenuating the signal
B	Removing unnecessary significant digits
C	Converting data to binary code decimal form
D	Reducing the effective sample rate by removing samples

36. - E7G02

What is the effect of ringing in a filter?

Select	Answer
A	Undesired oscillations added to the desired signal
B	Partial cancellation of the signal over a range of frequencies
C	A reduction in high frequency response
D	An echo caused by a long time delay

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Using the oscillator only for CW and digital signals
B	Mechanically isolating the oscillator circuitry from its enclosure
C	Eliminating noise on the oscillator's power supply
D	Use of NP0 capacitors

38. - E8A08

Why would a direct or flash conversion analog-to-digital converter be useful for a software defined radio?

Select	Answer
A	All of these choices are correct
B	Very high speed allows digitizing high frequencies
C	Immunity to out of sequence coding reduces spurious responses
D	Very low power consumption decreases frequency drift

39. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	2000
B	1/3
C	6000
D	3

40. - E8C07

What is the necessary bandwidth of a 4800-Hz frequency shift, 9600-baud ASCII FM transmission?

Select	Answer
A	4.8 kHz
B	9.6 kHz
C	15.36 kHz
D	5.76 kHz

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

Select	Answer
A	Excessive numbers of retries
B	Ground loops
C	Bit errors in the modem
D	Excessive transmit audio levels

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Install a good radial system
B	Shorten the radiating element
C	Reduce the diameter of the radiating element
D	Isolate the coax shield from ground

43. - E9B11

What is a disadvantage of decreasing the number of wire segments in an antenna model below the guideline of 10 segments per half-wavelength?

Select	Answer
A	Ground conductivity will not be accurately modeled
B	The antenna will become mechanically unstable
C	The computed feed point impedance may be incorrect
D	The resulting design will favor radiation of harmonic energy

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A type of ground-plane antenna
B	A dipole consisting of one wavelength of wire forming a very thin loop
C	A dipole configured to provide forward gain
D	A dipole one-quarter wavelength long

45. - E9D11

Which of the following types of conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	A wide flat copper strap
B	A single 12 gauge or 10 gauge stainless steel wire
C	A resistive wire, such as spark plug wire
D	A cable with six or seven 18 gauge conductors in parallel

46. - E9E12

What is the primary purpose of a phasing line when used with an antenna having multiple driven elements?

Select	Answer
A	It makes sure the antenna has a low-angle radiation pattern
B	It ensures that each driven element operates in concert with the others to create the desired antenna pattern
C	It prevents reflected power from traveling back down the feed line and causing harmonic radiation from the transmitter
D	It allows single-band antennas to operate on other bands

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	All of these choices are correct
B	Foam dielectric has higher velocity factor
C	Foam dielectric has lower safe operating voltage limits
D	Foam dielectric has lower loss per unit of length

48. - E9G10

What do the arcs on a Smith chart represent?

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

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It increases the sensitivity of a DF antenna array
B	It modifies the pattern of a DF antenna array to provide a null in one direction
C	It allows DF antennas to receive signals at different vertical angles
D	It provides diversity reception that cancels multipath signals

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations
B	Each transmitter operating with a duty-cycle greater than 50 percent
C	Only commercial transmitters
D	Only the most powerful transmitter

Figure E5-2

Figure E7-3