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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	12 meter band
B	30 meter band
C	60 meter band
D	17 meter band

2. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must file an Environmental Impact Statement with the EPA before construction begins
B	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of FCC rules
C	No special rules apply if your antenna structure will be less than 300 feet in height
D	You must obtain a construction permit from the airport zoning authority

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

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the ITU
B	All of these choices are correct
C	Any amateur station designated by NASA
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. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
B	A sentence of up to one year in prison
C	A fine of up to $1000 per occurrence
D	All of these choices are correct

6. - E1F12

Who may be the control operator of an auxiliary station?

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

7. - E2A14

What technology is used to track, in real time, balloons carrying amateur radio transmitters?

Select	Answer
A	Radar
B	Doppler shift of beacon signals
C	Bandwidth compressed LORAN
D	APRS

8. - E2B14

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

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

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Spread spectrum in the 2.4 GHz band
B	Store and forward on the 440 MHz band
C	Frequency division multiplex in the 24 GHz band
D	Multiple Frequency Shift Keying in the 10 GHz band

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

Select	Answer
A	AMTOR
B	170 Hz shift, 45 baud RTTY
C	300 baud packet
D	PSK31

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	RTTY
B	MFSK
C	PSK31
D	Winlink

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	Electric and magnetic fields become aligned as they travel
B	Changing electric and magnetic fields propagate the energy
C	The waves are reflected by the ionosphere and return to their source
D	The energy propagates through a medium with a high refractive index

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
B	Propagation between two stations at the same latitude
C	Propagation between any two points located on the magnetic equator
D	Propagation between two continents by way of ducts along the magnetic equator

14. - E3C08

What does the space weather term G5 mean?

Select	Answer
A	An extreme geomagnetic storm
B	Waning sunspot numbers
C	Moderate solar wind
D	Very low solar activity

15. - E4A08

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

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

16. - E4B10

Which of the following describes a method to measure intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a peak reading wattmeter
B	Modulate the transmitter with two non-harmonically related audio frequencies and observe the RF output with a spectrum analyzer
C	Modulate the transmitter with two non-harmonically related radio frequencies and observe the RF output with a spectrum analyzer
D	Modulate the transmitter with two harmonically related audio frequencies and observe the RF output with a logic analyzer

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 limits the receiver's ability to receive strong signals
C	It decreases receiver third-order intermodulation distortion dynamic range
D	It reduces receiver sensitivity

18. - E4D09

What is the purpose of the preselector in a communications receiver?

Select	Answer
A	To store often-used frequencies
B	To increase rejection of unwanted signals
C	To allow selection of the optimum RF amplifier device
D	To provide a range of AGC time constants

19. - E4E02

Which of the following types of receiver noise can often be reduced with a DSP noise filter?

Select	Answer
A	Broadband white noise
B	All of these choices are correct
C	Ignition noise
D	Power line noise

20. - E5A01

What can cause the voltage across reactances in series to be larger than the voltage applied to them?

Select	Answer
A	Capacitance
B	Resonance
C	Resistance
D	Conductance

21. - E5B12

What is admittance?

Select	Answer
A	The unit used for Q factor
B	The term for the gain of a field effect transistor
C	The turns ratio of a transformer
D	The inverse of impedance

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Rectangular coordinates
B	Faraday grid
C	Elliptical coordinates
D	Maidenhead grid

23. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	All of these choices are correct
B	To increase the thermal time constant
C	To maintain component lifetime
D	To avoid unwanted inductive reactance

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
B	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator
C	Only N-type semiconductor material can conduct current
D	Only P-type semiconductor material can conduct current

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Reverse bias
B	Zero bias
C	Forward bias
D	Inductive bias

26. - E6C07

What best describes a pull-up or pull-down resistor?

Select	Answer
A	A resistor in a keying circuit used to reduce key clicks
B	A resistor that insures that an oscillator frequency does not drive lower over time
C	A resistor connected to the positive or negative supply line used to establish a voltage when an input or output is an open circuit
D	A resistor connected to an op-amp output that only functions when the logic output is false

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Stabilizing current
B	Excitation current
C	Direct current
D	Magnetizing current

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	50 ohms
B	300 ohms
C	450 ohms
D	10 ohms

29. - E6F01

What is photoconductivity?

Select	Answer
A	The conversion of electromotive energy to photon energy
B	The conversion of photon energy to electromotive energy
C	The increased conductivity of an illuminated semiconductor
D	The decreased conductivity of an illuminated semiconductor

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B11

In Figure E7-1, what is the purpose of R3?

Select	Answer
A	Fixed bias
B	Emitter bypass
C	Self bias
D	Output load resistor

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It introduces transconductance to cancel the reactive part of impedance
B	It cancels the reactive part of the impedance and changes the resistive part to a desired value
C	It introduces negative resistance to cancel the resistive part of impedance
D	Network resistances are substituted for load resistances and reactances are matched to the resistances

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

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

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Phase comparator
B	Discriminator
C	Product detector
D	Phase detector

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	More taps
B	Double-precision math routines
C	Complex phasor representations
D	Higher data rate

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	For smoothing power supply output
B	As an audio filter in a receiver
C	As a high-pass filter used to block RFI at the input to receivers
D	As a low-pass filter used between a transmitter and a transmission line

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

Select	Answer
A	Through link coupling
B	Through a tapped coil
C	Through a capacitive divider
D	Through a neutralizing capacitor

38. - E8A12

What is an advantage of using digital signals instead of analog signals to convey the same information?

Select	Answer
A	Digital signals can be regenerated multiple times without error
B	Less complex circuitry is required for digital signal generation and detection
C	All of these choices are correct
D	Digital signals always occupy a narrower bandwidth

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	47
B	2.14
C	0.214
D	0.47

40. - E8C11

What is the relationship between symbol rate and baud?

Select	Answer
A	They are the same
B	Baud is only used for RTTY
C	Baud is twice the symbol rate
D	Symbol rate is only used for packet-based modes

41. - E8D07

What is a common cause of overmodulation of AFSK signals?

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

42. - E9A14

What is meant by the radiation resistance of an antenna?

Select	Answer
A	The specific impedance of the antenna
B	The value of a resistance that would dissipate the same amount of power as that radiated from an antenna
C	The resistance in the atmosphere that an antenna must overcome to be able to radiate a signal
D	The combined losses of the antenna elements and feed line

43. - E9B05

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

Select	Answer
A	Polarization
B	Elevation
C	Azimuth
D	Radiation resistance

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

45. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to a metal water pipe
B	A 50 ohm resistor connected to ground
C	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
D	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The delta match
B	The gamma match
C	The omega match
D	The stub match

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	The characteristic impedance is higher in a parallel feed line
B	Electrical signals move more slowly in a coaxial cable than in air
C	Skin effect is less pronounced in the coaxial cable
D	The surge impedance is higher in a parallel feed line

48. - E9G02

What type of coordinate system is used in a Smith chart?

Select	Answer
A	Resistance circles and reactance arcs
B	Resistance lines and reactance chords
C	Voltage circles and current arcs
D	Voltage lines and current chords

49. - E9H10

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

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

50. - E0A08

What does SAR measure?

Select	Answer
A	The rate at which RF energy is absorbed by the body
B	The rate of RF energy reflected from stationary terrain
C	Synthetic Aperture Ratio of the human body
D	Signal Amplification Rating

Figure E7-1

Figure E9-2