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

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1. - E1A11

Which of the following describes authorization or licensing required when operating an amateur station aboard a U.S.-registered vessel in international waters?

Select	Answer
A	Any amateur license with an FCC Marine or Aircraft endorsement
B	An unrestricted Radiotelephone Operator Permit
C	Only General class or higher amateur licenses
D	Any FCC-issued amateur license

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

3. - E1C05

When may an automatically controlled station originate third party communications?

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

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 and 33 cm
C	70 cm only
D	33 cm and 13 cm

5. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Employees of the VE
B	Relatives of the VE as listed in the FCC rules
C	Friends of the VE
D	All of these choices are correct

6. - E1F06

Under what circumstances might the FCC issue a Special Temporary Authority (STA) to an amateur station?

Select	Answer
A	To allow regular operation on Land Mobile channels
B	To provide additional spectrum for personal use
C	To provide temporary operation while awaiting normal licensing
D	To provide for experimental amateur communications

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	A linearly polarized antenna
B	A circularly polarized antenna
C	An isotropic antenna
D	A log-periodic dipole array

8. - E2B18

On which of the following frequencies is one likely to find FM ATV transmissions?

Select	Answer
A	52.525 MHz
B	1255 MHz
C	14.230 MHz
D	29.6 MHz

9. - E2C02

Which of the following best describes the term self-spotting in regards to HF contest operating?

Select	Answer
A	A manual technique for rapidly zero beating or tuning to a station's frequency before calling that station
B	An automatic method for rapidly zero beating or tuning to a station's frequency before calling that station
C	The generally prohibited practice of posting one's own call sign and frequency on a spotting network
D	The acceptable practice of manually posting the call signs of stations on a spotting network

10. - E2D13

What type of modulation is used for JT65 contacts?

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

11. - E2E07

What is the typical bandwidth of a properly modulated MFSK16 signal?

Select	Answer
A	31 Hz
B	2.16 kHz
C	550 Hz
D	316 Hz

12. - E3A10

Which type of atmospheric structure can create a path for microwave propagation?

Select	Answer
A	Temperature inversion
B	Wind shear
C	The jet stream
D	Dust devil

13. - E3B01

What is transequatorial propagation?

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

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	10 percent greater
B	Twice as great
C	Four times as great
D	50 percent greater

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	Automatic amplitude and frequency numerical readout
B	Manipulation of time base after trace capture
C	Storage of traces for future reference
D	All of these choices are correct

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	146.52 Hz
B	10 Hz
C	146.52 kHz
D	1465.20 Hz

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

Select	Answer
A	It improves sensitivity by reducing front end noise
B	All of these choices are correct
C	It improves dynamic range by attenuating strong signals near the receive frequency
D	It improves intelligibility by using low Q circuitry to reduce ringing

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

19. - E4E04

How can conducted and radiated noise caused by an automobile alternator be suppressed?

Select	Answer
A	By installing a high-pass filter in series with the radio's power lead and a low-pass filter in parallel with the field lead
B	By installing a noise suppression resistor and a blocking capacitor in both leads
C	By installing filter capacitors in series with the DC power lead and a blocking capacitor in the field lead
D	By connecting the radio's power leads directly to the battery and by installing coaxial capacitors in line with the alternator leads

20. - E5A13

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

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

21. - E5B05

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

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

22. - E5C06

What does the impedance 50-j25 represent?

Select	Answer
A	25 ohms resistance in series with 50 ohms capacitive reactance
B	50 ohms resistance in series with 25 ohms inductive reactance
C	25 ohms resistance in series with 50 ohms inductive reactance
D	50 ohms resistance in series with 25 ohms capacitive reactance

23. - E5D02

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

Select	Answer
A	To maintain component lifetime
B	To increase the thermal time constant
C	All of these choices are correct
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 P-type semiconductor material can conduct current
D	Only N-type semiconductor material can conduct current

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	A large region of intrinsic material
B	Reverse bias controls its forward voltage drop
C	Extremely high reverse breakdown voltage
D	Ability to dissipate large amounts of power

26. - E6C09

What is a Programmable Logic Device (PLD)?

Select	Answer
A	A programmable collection of logic gates and circuits in a single integrated circuit
B	An algorithm for simulating logic functions during circuit design
C	Programmable equipment used for testing digital logic integrated circuits
D	A device to control industrial equipment

27. - E6D13

What is the primary cause of inductor self-resonance?

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

28. - E6E09

Which of the following component package types would be most suitable for use at frequencies above the HF range?

Select	Answer
A	Surface mount
B	TO-220
C	Axial lead
D	Radial lead

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The effective payback period
B	The open-circuit voltage divided by the short-circuit current under full illumination
C	The output RF power divided by the input DC power
D	The relative fraction of light that is converted to current

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It stores one bit of data in either a 0 or 1 state
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It maintains a constant output voltage, regardless of variations in the input voltage
D	It produces a continuous square wave oscillating between 1 and 0

31. - E7B13

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

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

32. - E7C11

Which of the following is the common name for a filter network which is equivalent to two L-networks connected back-to-back with the two inductors in series and the capacitors in shunt at the input and output?

Select	Answer
A	Pi
B	Omega
C	Cascode
D	Pi-L

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	A Zener diode
C	An SCR
D	A tunnel diode

34. - E7E05

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

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

35. - E7F17

What do the letters I and Q in I/Q Modulation represent?

Select	Answer
A	Inactive and Quiescent
B	Instantaneous and Quasi-stable
C	Instantaneous and Quenched
D	In-phase and Quadrature

36. - E7G01

What is the typical output impedance of an integrated circuit op-amp?

Select	Answer
A	1000 ohms
B	Very high
C	100 ohms
D	Very low

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	NP0 capacitors
B	Toroidal inductors
C	Wirewound resistors
D	Non-inductive resistors

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

Select	Answer
A	A square wave
B	A cosine wave
C	A sine wave
D	A sawtooth wave

39. - E8B02

How does the modulation index of a phase-modulated emission vary with RF carrier frequency (the modulated frequency)?

Select	Answer
A	It varies with the square root of the RF carrier frequency
B	It does not depend on the RF carrier frequency
C	It decreases as the RF carrier frequency increases
D	It increases as the RF carrier frequency increases

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By the receiving station repeating each block of three data characters
B	By transmitting extra data that may be used to detect and correct transmission errors
C	By varying the frequency shift of the transmitted signal according to a predefined algorithm
D	By transmitting a special algorithm to the receiving station along with the data characters

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

Select	Answer
A	Repeat Request Rate (RRR)
B	Signal to noise ratio
C	Baud rate
D	Intermodulation Distortion (IMD)

42. - E9A04

Which of the following factors may affect the feed point impedance of an antenna?

Select	Answer
A	The settings of an antenna tuner at the transmitter
B	Transmission-line length
C	Antenna height, conductor length/diameter ratio and location of nearby conductive objects
D	Sunspot activity and time of day

43. - E9B09

What type of computer program technique is commonly used for modeling antennas?

Select	Answer
A	Graphical analysis
B	Method of Moments
C	Calculus differentiation with respect to physical properties
D	Mutual impedance analysis

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It changes the radiation pattern from horizontal to vertical polarization
C	It reflects the standing waves on the antenna elements back to the transmitter
D	It changes the radiation pattern from bidirectional to unidirectional

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain does not change
B	Gain increases by 6 dB
C	Gain is multiplied by 0.707
D	Gain increases by 3 dB

46. - E9E04

What is the purpose of the series capacitor in a gamma-type antenna matching network?

Select	Answer
A	To transform the antenna impedance to a higher value
B	To provide a rejection notch that prevents the radiation of harmonics
C	To provide DC isolation between the feed line and the antenna
D	To cancel the inductive reactance of the matching network

47. - E9F04

What is the typical velocity factor for a coaxial cable with solid polyethylene dielectric?

Select	Answer
A	0.10
B	2.70
C	0.66
D	0.30

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Free space radiation directivity chart
B	Smith chart
C	Azimuth angle radiation pattern chart
D	Elevation angle radiation pattern chart

49. - E9H06

What is the triangulation method of direction finding?

Select	Answer
A	A fixed receiving station uses three different antennas to plot the location of the signal source
B	Antenna headings from several different receiving locations are used to locate the signal source
C	A fixed receiving station plots three headings to the signal source
D	The geometric angles of sky waves from the source are used to determine its position

50. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Hearing loss caused by high voltage corona discharge
B	Blood clotting from the intense magnetic field
C	Localized heating of the body from RF exposure in excess of the MPE limits
D	Ingestion of ozone gas from the cooling system

Figure E7-2

Figure E9-3