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

Logging in (or registering) will help the system to select questions that you need to focus on.

1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Discontinue forwarding the communication as soon as you become aware of it
B	Notify the nearest FCC Field Engineer's office
C	Notify the originating station that the communication does not comply with FCC rules
D	Discontinue forwarding all messages

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 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 a control link between a control point and a locally controlled station
B	Remotely controlling a station's antenna pattern through a directional control link
C	A station operating with its output power controlled automatically
D	The use of devices and procedures for control so that the control operator does not have to be present at a control point

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	Any amateur station designated by NASA
C	All of these choices are correct
D	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator

5. - E1E02

Where are the questions for all written U.S. amateur license examinations listed?

Select	Answer
A	In the appropriate FCC Report and Order
B	In a question pool maintained by all the VECs
C	In FCC Part 97
D	In a question pool maintained by the FCC

6. - E1F05

Amateur stations may not transmit in which of the following frequency segments if they are located in the contiguous 48 states and north of Line A?

Select	Answer
A	53 MHz - 54 MHz
B	440 MHz - 450 MHz
C	420 MHz - 430 MHz
D	222 MHz - 223 MHz

7. - E2A12

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

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

8. - E2B07

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

Select	Answer
A	Hue
B	Luminance
C	Chroma
D	Spectral Intensity

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	33 cm
B	6 m
C	2 m
D	30 m

10. - E2D03

Which of the following digital modes is especially useful for EME communications?

Select	Answer
A	JT65
B	FSK441
C	Olivia
D	PACTOR III

11. - E2E13

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	All of these choices are correct
B	Your transmit frequency is incorrect
C	The protocol version you are using is not the supported by the digital station
D	Another station you are unable to hear is using the frequency

12. - E3A12

What is the cause of auroral activity?

Select	Answer
A	A low sunspot level combined with tropospheric ducting
B	Meteor showers concentrated in the extreme northern and southern latitudes
C	The interaction in the F2 layer between the solar wind and the Van Allen belt
D	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field

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. - E3C11

What does VOACAP software model?

Select	Answer
A	AC voltage and impedance
B	HF propagation
C	VHF radio propagation
D	AC current and impedance

15. - E4A08

Which of the following instrument would be best for measuring the SWR of a beam antenna?

Select	Answer
A	An ohmmeter
B	A spectrum analyzer
C	A Q meter
D	An antenna analyzer

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	1.4652 MHz
B	165.2 Hz
C	14.652 kHz
D	146.52 Hz

17. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a conventional HF or VHF communications receiver?

Select	Answer
A	Easier for front-end circuitry to eliminate image responses
B	Improved receiver noise figure
C	Reduced drift
D	Fewer components in the receiver

18. - E4D13

Which of the following can cause receiver desensitization?

Select	Answer
A	Audio gain adjusted too low
B	Squelch gain misadjusted
C	Strong adjacent channel signals
D	Audio bias adjusted too high

19. - E4E05

How can noise from an electric motor be suppressed?

Select	Answer
A	By installing a high pass filter in series with the motor's power leads
B	By using a ground-fault current interrupter in the circuit used to power the motor
C	By installing a brute-force AC-line filter in series with the motor leads
D	By installing a bypass capacitor in series with the motor leads

20. - E5A17

What is the result of increasing the Q of an impedance-matching circuit?

Select	Answer
A	Matching bandwidth is decreased
B	It has no effect on impedance matching
C	Matching range is increased
D	Matching bandwidth is increased

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	440 seconds
B	55 seconds
C	220 seconds
D	110 seconds

22. - E5C05

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

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

23. - E5D08

What type of energy is stored in an electromagnetic or electrostatic field?

Select	Answer
A	Potential energy
B	Electromechanical energy
C	Thermodynamic energy
D	Kinetic energy

24. - E6A05

What is the alpha of a bipolar junction transistor?

Select	Answer
A	The change of collector current with respect to base current
B	The change of base current with respect to collector current
C	The change of collector current with respect to gate current
D	The change of collector current with respect to emitter current

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Junction
B	Tunnel
C	Point contact
D	Zener

26. - E6C08

In Figure E6-5, what is the schematic symbol for a NAND gate?

Select	Answer
A	2
B	3
C	1
D	4

27. - E6D13

What is the primary cause of inductor self-resonance?

Select	Answer
A	Inductive kickback
B	The skin effect
C	Non-linear core hysteresis
D	Inter-turn capacitance

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Stripped lead
B	Direct soldering
C	Virtual lead mounting
D	Surface mount

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	A heavy metal
B	An ordinary metal
C	A crystalline semiconductor
D	A liquid semiconductor

30. - E7A01

Which is a bi-stable circuit?

Select	Answer
A	A clock
B	An "AND" gate
C	A flip-flop
D	An "OR" gate

31. - E7B02

What is a Class D amplifier?

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

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	L-networks cannot perform impedance transformation
C	Pi-networks have fewer components
D	Pi-networks are designed for balanced input and output

33. - E7D15

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

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

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	To reduce impulse noise reception
B	To remove third-order distortion products
C	For higher efficiency
D	For compatibility with transmitters using phase modulation

35. - E7F10

What aspect of receiver analog-to-digital conversion determines the maximum receive bandwidth of a Direct Digital Conversion SDR?

Select	Answer
A	Sample rate
B	Sample clock phase noise
C	Processor latency
D	Sample width in bits

36. - E7G02

What is the effect of ringing in a filter?

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

37. - E7H07

How can an oscillator's microphonic responses be reduced?

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

38. - E8A09

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

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

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Percentage of modulation
B	Quieting index
C	Modulation index
D	FM compressibility

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 26 Hz
B	Approximately 13 Hz
C	Approximately 104 Hz
D	Approximately 52 Hz

41. - E8D10

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

Select	Answer
A	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
B	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
C	Baudot uses 7 data bits per character, ASCII uses 8; Baudot has no letters/figures shift code, ASCII uses 2 letters/figures shift codes
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. - E9A13

How much gain does an antenna have compared to a 1/2-wavelength dipole when it has 12 dB gain over an isotropic antenna?

Select	Answer
A	9.85 dB
B	14.15 dB
C	6.17 dB
D	12.5 dB

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Polarization
B	Azimuth
C	Radiation resistance
D	Elevation

44. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	50 ohms
B	300 ohms
C	72 ohms
D	450 ohms

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	No change occurs
B	It is decreased
C	It is increased
D	It becomes flat

46. - E9E05

How must the driven element in a 3-element Yagi be tuned to use a hairpin matching system?

Select	Answer
A	The driven element reactance must be inductive
B	The driven element resonance must be lower than the operating frequency
C	The driven element radiation resistance must be higher than the characteristic impedance of the transmission line
D	The driven element reactance must be capacitive

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

48. - E9G11

How are the wavelength scales on a Smith chart calibrated?

Select	Answer
A	In fractions of transmission line electrical wavelength
B	In fractions of transmission line electrical frequency
C	In fractions of antenna electrical frequency
D	In fractions of antenna electrical wavelength

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It narrows the bandwidth of the received signal to improve signal to noise ratio
B	It prevents receiver overload which could make it difficult to determine peaks or nulls
C	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity
D	It compensates for the effects of an isotropic antenna, thereby improving directivity

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

Figure E6-5

Figure E9-2