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	170 Hz
D	60 Hz

2. - E1B08

What limitations may the FCC place on an amateur station if its signal causes interference to domestic broadcast reception, assuming that the receivers involved are of good engineering design?

Select	Answer
A	The amateur station must cease operation
B	The amateur station must avoid transmitting during certain hours on frequencies that cause the interference
C	The amateur station must cease operation on all frequencies below 30 MHz
D	The amateur station must cease operation on all frequencies above 30 MHz

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

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	One-way transmission of measurements at a distance from the measuring instrument
B	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
C	Two-way radiotelephone transmissions in excess of 1000 feet
D	Two-way single channel transmissions of data

5. - E1E06

Who is responsible for the proper conduct and necessary supervision during an amateur operator license examination session?

Select	Answer
A	The VE session manager
B	The VEC coordinating the session
C	Each administering VE
D	The FCC

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 50 MHz
B	Only on amateur frequencies above 144 MHz
C	Only on amateur frequencies above 222 MHz
D	Only on amateur frequencies above 420 MHz

7. - E2A08

Why should effective radiated power to a satellite which uses a linear transponder be limited?

Select	Answer
A	To prevent creating errors in the satellite telemetry
B	To prevent the satellite from emitting out-of-band signals
C	To avoid interfering with terrestrial QSOs
D	To avoid reducing the downlink power to all other users

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	Vestigial sideband provides high frequency emphasis to sharpen the picture
B	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry
C	The vestigial sideband carries the audio information
D	The vestigial sideband contains chroma information

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send the call sign of the DX station three times, the words "this is", then your call sign three times
B	Send your full call sign once or twice
C	Send your full call sign and grid square
D	Send only the last two letters of your call sign until you make contact

10. - E2D01

Which of the following digital modes is especially designed for use for meteor scatter signals?

Select	Answer
A	APRS
B	WSPR
C	FSK441
D	Hellschreiber

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Audio FSK has a superior frequency response
B	Direct FSK uses a DC-coupled data connection
C	Audio FSK can be performed anywhere in the transmit chain
D	Direct FSK applies the data signal to the transmitter VFO

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Gray-line
B	Lightning discharges
C	Warm and cold fronts
D	Sprites and jets

13. - E3B12

What is the primary characteristic of chordal hop propagation?

Select	Answer
A	Successive ionospheric reflections without an intermediate reflection from the ground
B	Propagation away from the great circle bearing between stations
C	Propagation across the geomagnetic equator
D	Signals reflected back toward the transmitting station

14. - E3C14

Why does the radio-path horizon distance exceed the geometric horizon?

Select	Answer
A	D-region skip
B	Downward bending due to density variations in the atmosphere
C	E-region skip
D	Downward bending due to aurora refraction

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 multiplies a higher frequency signal so a low-frequency counter can display the operating frequency
C	It divides a higher frequency signal so a low-frequency counter can display the input frequency
D	It prevents oscillation in a low-frequency counter circuit

16. - E4B17

What three test loads are used to calibrate a standard RF vector network analyzer?

Select	Answer
A	Short circuit, open circuit, and 50 ohms
B	Short circuit, open circuit, and resonant circuit
C	50 ohms, 75 ohms, and 90 ohms
D	50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

Select	Answer
A	A notch filter
B	A narrow IF filter
C	A front-end filter or pre-selector
D	A properly adjusted product detector

18. - E4D05

What transmitter frequencies would cause an intermodulation-product signal in a receiver tuned to 146.70 MHz when a nearby station transmits on 146.52 MHz?

Select	Answer
A	146.34 MHz and 146.61 MHz
B	146.10 MHz and 147.30 MHz
C	146.88 MHz and 146.34 MHz
D	173.35 MHz and 139.40 MHz

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	FM signals can no longer be demodulated
D	The audio frequency bandwidth of the received signal might be compressed

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Fewer components are needed for the same performance
B	Internal voltages and circulating currents increase
C	Parasitic effects are minimized
D	Phase shift can become uncontrolled

21. - E5B10

What is the relationship between the current through an inductor and the voltage across an inductor?

Select	Answer
A	Voltage and current are in phase
B	Voltage and current are 180 degrees out of phase
C	Current leads voltage by 90 degrees
D	Voltage leads current by 90 degrees

22. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Venn diagram
B	Near field diagram
C	Phasor diagram
D	Far field diagram

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	355 W
B	252 W
C	1.42 mW
D	704 W

24. - E6A11

In Figure E6-2, what is the schematic symbol for a P-channel junction FET?

Select	Answer
A	2
B	3
C	1
D	6

25. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Zener diode
B	Silicon-controlled rectifier
C	Varactor diode
D	Tunnel diode

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	A PGA contains its own internal power supply
C	Many similar gates are less expensive than a mixture of gate types
D	All of these choices are correct

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores exhibit greater hysteresis
B	Toroidal cores have lower Q characteristics
C	Toroidal cores confine most of the magnetic field within the core material
D	Toroidal cores make it easier to couple the magnetic energy into other components

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Silicon
B	Silicon dioxide
C	Silicon nitride
D	Gallium nitride

29. - E6F12

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

Select	Answer
A	Holes
B	Electrons
C	Protons
D	Photons

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

31. - E7B13

In Figure E7-2, what is the purpose of R?

Select	Answer
A	Voltage regulation
B	Collector load
C	Emitter load
D	Fixed bias

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	An audio filter made with four quartz crystals that resonate at 1kHz intervals
B	A power supply filter made with interlaced quartz crystals
C	A filter with narrow bandwidth and steep skirts made using quartz crystals
D	A filter with wide bandwidth and shallow skirts made using quartz crystals

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	The conduction of a control element is varied to maintain a constant output voltage
B	The control element duty cycle is proportional to the line or load conditions
C	It eliminates the need for a pass transistor
D	It has a ramp voltage as its output

34. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A de-emphasis network
B	A heterodyne suppressor
C	A pre-emphasis network
D	An audio prescaler

35. - E7F07

What function can a Fast Fourier Transform perform?

Select	Answer
A	Converting analog signals to digital form
B	Converting 8-bit data to 16 bit data
C	Converting digital signals from the time domain to the frequency domain
D	Converting digital signals to analog form

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	0.07
C	7
D	14

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Colpitts and Hartley
B	Negative feedback and balanced feedback
C	Pierce and Zener
D	Armstrong and deForest

38. - E8A11

What type of information can be conveyed using digital waveforms?

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

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the audio modulating frequency to the center carrier 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 highest audio modulating frequency to the average audio modulating frequency

40. - E8C04

What technique is used to minimize the bandwidth requirements of a PSK31 signal?

Select	Answer
A	Use of trapezoidal data pulses
B	Use of sinusoidal data pulses
C	Reed-Solomon character encoding
D	Zero-sum character encoding

41. - E8D10

What are some of the differences between the Baudot digital code and ASCII?

Select	Answer
A	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
B	Baudot uses 6 data bits per character, ASCII uses 7 or 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
C	Baudot uses 5 data bits per character, ASCII uses 7 or 8; Baudot uses 2 characters as letters/figures shift codes, ASCII has no letters/figures shift code
D	Baudot uses 4 data bits per character, ASCII uses 7 or 8; Baudot uses 1 character as a letters/figures shift code, ASCII has no letters/figures code

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Yagi
B	Half-wave dipole
C	Isotropic antenna
D	Quarter-wave vertical

43. - E9B03

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

Select	Answer
A	18 dB
B	14 dB
C	24 dB
D	12 dB

44. - E9C08

What is a folded dipole antenna?

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

45. - E9D09

What is the function of a loading coil used as part of an HF mobile antenna?

Select	Answer
A	To lower the Q
B	To lower the losses
C	To increase the SWR bandwidth
D	To cancel capacitive reactance

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	Hairpin match
B	Double-bazooka match
C	Gamma match
D	All of these choices are correct

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

Select	Answer
A	Very high impedance
B	The same as the characteristic impedance of the line
C	The same as the output impedance of the generator
D	Very low impedance

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	Polar axis
B	Reactance axis
C	Prime axis
D	Impedance axis

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A vertical antenna coupled to a feed line through an inductive loop of wire
B	One or more turns of wire wound in the shape of a large open coil
C	A large circularly polarized antenna
D	A small coil of wire tightly wound around a toroidal ferrite core

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	Mica
B	Beryllium Oxide
C	Uranium Hexafluoride
D	Zinc oxide

Figure E6-2

Figure E7-2

Figure E7-4

Figure E9-1

Figure E9-3