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

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1. - E1A10

If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?

Select	Answer
A	Its operation must be approved by the master of the ship or the pilot in command of the aircraft
B	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use
C	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
D	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply

2. - E1B07

What is the highest modulation index permitted at the highest modulation frequency for angle modulation below 29.0 MHz?

Select	Answer
A	0.5
B	3.0
C	2.0
D	1.0

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When approved by the National Telecommunication and Information Administration
B	When agreed upon by the sending or receiving station
C	Never
D	Only when transmitting RTTY or data emissions

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must be capable of terminating transmissions by telecommand when directed by the FCC
B	All of these choices are correct
C	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
D	The space station must cease all transmissions after 5 years

5. - E1E03

What is a Volunteer Examiner Coordinator?

Select	Answer
A	The person who has entered into an agreement with the FCC to be the VE session manager
B	A person who has volunteered to administer amateur operator license examinations
C	A person who has volunteered to prepare amateur operator license examinations
D	An organization that has entered into an agreement with the FCC to coordinate amateur operator license examinations

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	All privileges of the Extra Class license
B	None, they must obtain a U.S. license
C	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
D	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of ionospheric absorption
B	Because of the Doppler Effect
C	Because the satellite is spinning
D	Because of the satellite's low orbital altitude

8. - E2B04

What is blanking in a video signal?

Select	Answer
A	Turning off the scanning beam while it is traveling from right to left or from bottom to top
B	Turning off the scanning beam at the conclusion of a transmission
C	Transmitting a black and white test pattern
D	Synchronization of the horizontal and vertical sync pulses

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 middle of the band, usually 25 kHz above the national calling frequency
C	In the middle of each band, usually on the national calling frequency
D	In the weak signal segment of the band, with most of the activity near the calling frequency

10. - E2D13

What type of modulation is used for JT65 contacts?

Select	Answer
A	RTTY
B	PSK
C	Multi-tone AFSK
D	IEEE 802.11

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	PACTOR
B	MT63
C	PSK31
D	RTTY

12. - E3A08

When a meteor strikes the Earth's atmosphere, a cylindrical region of free electrons is formed at what layer of the ionosphere?

Select	Answer
A	The E layer
B	The D layer
C	The F2 layer
D	The F1 layer

13. - E3B12

What is the primary characteristic of chordal hop propagation?

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

14. - E3C14

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

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

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	Amount of memory on the soundcard
C	All of these choices are correct
D	Analog-to-digital conversion speed of the soundcard

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	146.52 kHz
C	10 Hz
D	146.52 Hz

17. - E4C01

What is an effect of excessive phase noise in the local oscillator section of a receiver?

Select	Answer
A	It can cause strong signals on nearby frequencies to interfere with reception of weak signals
B	It reduces receiver sensitivity
C	It limits the receiver's ability to receive strong signals
D	It decreases receiver third-order intermodulation distortion dynamic range

18. - E4D12

What is the term for the reduction in receiver sensitivity caused by a strong signal near the received frequency?

Select	Answer
A	Squelch gain rollback
B	Desensitization
C	Cross-modulation interference
D	Quieting

19. - E4E16

What current flows equally on all conductors of an unshielded multi-conductor cable?

Select	Answer
A	Return current
B	Reactive current only
C	Common-mode current
D	Differential-mode current

20. - E5A04

What is the magnitude of the impedance of a circuit with a resistor, an inductor and a capacitor all in parallel, at resonance?

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

21. - E5B05

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

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

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By Y and G values
B	By X and R values
C	By real and imaginary parts
D	By phase angle and amplitude

23. - E5D03

What is microstrip?

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

24. - E6A15

Which semiconductor material contains excess holes in the outer shell of electrons?

Select	Answer
A	Bipolar-type
B	Superconductor-type
C	P-type
D	N-type

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Enhanced carrier retention time
B	Much higher reverse voltage breakdown
C	Less forward voltage drop
D	Controlled reverse avalanche voltage

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To allow the comparator to be used with AC input signal
B	To prevent input noise from causing unstable output signals
C	To increase the sensitivity
D	To cause the output to change states continually

27. - E6D14

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

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

28. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	-20 dBm
B	44 dBm
C	2 dB
D	-10 dB

29. - E6F02

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

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

30. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic "0" at its output only if all inputs are logic "0"
B	It produces logic "1" at its output only if all inputs are logic "1"
C	It produces logic "0" at its output if any single input is logic "1"
D	It produces logic "1" at its output if any single input is logic "1"

31. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Common collector
B	Common emitter
C	Emitter follower
D	Common base

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Greater harmonic suppression
B	Higher efficiency
C	Lower losses
D	Greater transformation range

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Input voltage multiplied by input current
B	Voltage difference from input to output multiplied by output current
C	Input voltage divided by output current
D	Output voltage multiplied by output current

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce PM signals by using an electrically variable resistance
B	To produce AM signals by using an electrically variable inductance or capacitance
C	To produce PM signals by using an electrically variable inductance or capacitance
D	To produce AM signals by using an electrically variable resistance

35. - E7F09

Why is an anti-aliasing digital filter required in a digital decimator?

Select	Answer
A	It removes low frequency signal components to eliminate the need for DC restoration
B	It peaks the response of the decimator, improving bandwidth
C	It notches out the sampling frequency to avoid sampling errors
D	It removes high-frequency signal components which would otherwise be reproduced as lower frequency components

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	0.03
B	38
C	1
D	76

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

Select	Answer
A	Pierce, Fenner and Beane
B	Taft, Pierce and negative feedback
C	Colpitts, Hartley and Pierce
D	Taft, Hartley and Pierce

38. - E8A07

What determines the PEP-to-average power ratio of a single-sideband phone signal?

Select	Answer
A	The degree of carrier suppression
B	The amplifier gain
C	The frequency of the modulating signal
D	The characteristics of the modulating signal

39. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	2.14
B	0.214
C	0.47
D	47

40. - E8C03

When performing phase shift keying, why is it advantageous to shift phase precisely at the zero crossing of the RF carrier?

Select	Answer
A	It is easier to demodulate with a conventional, non-synchronous detector
B	This results in the least possible transmitted bandwidth for the particular mode
C	It improves carrier suppression
D	All of these choices are correct

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

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

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	Antenna gain
B	SWR vs frequency charts
C	All of these choices are correct
D	Polar plots of the far field elevation and azimuth patterns

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	The high-angle radiation increases
B	The low-angle radiation decreases
C	The low-angle radiation increases
D	Both the high-angle and low-angle radiation decrease

45. - E9D09

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

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

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

47. - E9F01

What is the velocity factor of a transmission line?

Select	Answer
A	The ratio of the characteristic impedance of the line to the terminating impedance
B	The index of shielding for coaxial cable
C	The velocity of the wave in the transmission line divided by the velocity of light in a vacuum
D	The velocity of the wave in the transmission line multiplied by the velocity of light in a vacuum

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning resistance values with regard to the reactance axis
B	Reassigning impedance values with regard to the prime center
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning prime center with regard to the reactance axis

49. - E9H05

What is the main drawback of a wire-loop antenna for direction finding?

Select	Answer
A	It has a bidirectional pattern
B	It receives equally well in all directions
C	It is non-rotatable
D	It is practical for use only on VHF bands

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	E field and H field radiation intensity peaks can occur at different locations
B	The body reacts to electromagnetic radiation from both the E and H fields
C	Ground reflections and scattering make the field impedance vary with location
D	All of these choices are correct

Figure E7-1

Figure E7-4