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	The amateur station must have a power supply that is completely independent of the main ship or aircraft power supply
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	Its operation must be approved by the master of the ship or the pilot in command of the aircraft

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

3. - E1C13

Which of the following is required in order to operate in accordance with CEPT rules in foreign countries where permitted?

Select	Answer
A	You must identify in the official language of the country in which you are operating
B	You must bring a copy of FCC Public Notice DA 11-221
C	You must append "/CEPT" to your call sign
D	The U.S. embassy must approve of your operation

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	2 meters
B	6 meters and 2 meters
C	6 meters, 2 meters, and 1.25 meters
D	2 meters and 1.25 meters

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	Providing amateur operator license examination preparation training materials
B	No expenses are authorized for reimbursement
C	Preparing, processing, administering and coordinating an examination for an amateur radio license
D	Teaching an amateur operator license examination preparation course

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications that have a political content, except as allowed by the Fairness Doctrine
B	Communications in a language other than English
C	Communications that have a religious content
D	Communications transmitted for hire or material compensation, except as otherwise provided in the rules

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	435 MHz - 438 MHz
B	50.0 MHz - 50.2 MHz
C	144 MHz - 146 MHz
D	29.5 MHz - 29.7 MHz

8. - E2B18

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

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

9. - E2C12

What might help to restore contact when DX signals become too weak to copy across an entire HF band a few hours after sunset?

Select	Answer
A	Wait 24 hours before attempting another communication on the band
B	Switch to a higher frequency HF band
C	Switch to a lower frequency HF band
D	Wait 90 minutes or so for the signal degradation to pass

10. - E2D12

How does JT65 improve EME communications?

Select	Answer
A	All of these choices are correct
B	It controls the receiver to track Doppler shift
C	It supplies signals to guide the antenna to track the Moon
D	It can decode signals many dB below the noise floor using FEC

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	The mark and space signal have been inverted
B	The receiver has drifted 5 kHz from the desired receive frequency
C	One of the signal filters is saturated
D	Selective fading has occurred

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of two electric fields at parallel right angles to each other
B	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
C	A wave consisting of two magnetic fields at right angles to each other
D	A wave of alternating current, in the core of an electromagnet

13. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	80 meters
B	20 meters
C	6 meters
D	10 meters

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Sporadic-E
B	Polar paths
C	Transequatorial propagation
D	NVIS

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	All of these choices are correct
B	Attenuate the transmitter output going to the spectrum analyzer
C	Use high quality double shielded coaxial cables to reduce signal losses
D	Match the antenna to the load

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	165.2 Hz
B	146.52 Hz
C	14.652 kHz
D	1.4652 MHz

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

18. - E4D12

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

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

19. - E4E08

What type of signal is picked up by electrical wiring near a radio antenna?

Select	Answer
A	Harmonics of the AC power line frequency
B	A differential-mode signal at the AC power line frequency
C	An electrical-sparking signal
D	A common-mode signal at the frequency of the radio transmitter

20. - E5A14

What is the resonant frequency of a series RLC circuit if R is 22 ohms, L is 50 microhenrys and C is 40 picofarads?

Select	Answer
A	3.56 MHz
B	1.78 MHz
C	22.36 MHz
D	44.72 MHz

21. - E5B12

What is admittance?

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

22. - E5C15

Which point in Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and an 18 microhenry inductor at 3.505 MHz?

Select	Answer
A	Point 8
B	Point 7
C	Point 3
D	Point 1

23. - E5D10

How can the true power be determined in an AC circuit where the voltage and current are out of phase?

Select	Answer
A	By multiplying the reactive power times the power factor
B	By dividing the reactive power by the power factor
C	By dividing the apparent power by the power factor
D	By multiplying the apparent power times the power factor

24. - E6A14

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has low input impedance; a bipolar transistor has high input impedance
B	An FET has high input impedance; a bipolar transistor has low input impedance
C	They are both low impedance
D	They are both high impedance

25. - E6B04

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

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

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	Input signals are stronger
B	The input switching threshold is about two times the power supply voltage
C	The input switching threshold is about one-half the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D05

What is one reason for using ferrite cores rather than powdered-iron in an inductor?

Select	Answer
A	Ferrite toroids generally require fewer turns to produce a given inductance value
B	Ferrite toroids generally have better temperature stability
C	Ferrite toroids are easier to use with surface mount technology
D	Ferrite toroids generally have lower initial permeability

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	Gallium nitride
C	Silicon dioxide
D	Silicon nitride

29. - E6F02

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

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

30. - E7A04

How many flip-flops are required to divide a signal frequency by 4?

Select	Answer
A	8
B	1
C	2
D	4

31. - E7B12

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

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

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-L
B	Cascode
C	Pi
D	Omega

33. - E7D15

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

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

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce PM signals
B	By varying the tuning of a microphone preamplifier to produce AM signals
C	By varying the tuning of an amplifier tank circuit to produce AM signals
D	By varying the tuning of an amplifier tank circuit to produce PM signals

35. - E7F02

What kind of digital signal processing audio filter is used to remove unwanted noise from a received SSB signal?

Select	Answer
A	A Hilbert-transform filter
B	A crystal-lattice filter
C	An adaptive filter
D	A phase-inverting filter

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It decreases logarithmically with increasing frequency
B	It increases linearly with increasing frequency
C	It decreases linearly with increasing frequency
D	It does not vary with frequency

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A06

What is the approximate ratio of PEP-to-average power in a typical single-sideband phone signal?

Select	Answer
A	2.5 to 1
B	100 to 1
C	1 to 1
D	25 to 1

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the carrier center frequency to the audio modulating frequency
B	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
C	The ratio of the audio modulating frequency to the center carrier frequency
D	The ratio of the highest audio modulating frequency to the average audio modulating frequency

40. - E8C11

What is the relationship between symbol rate and baud?

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

41. - E8D02

What spread spectrum communications technique uses a high speed binary bit stream to shift the phase of an RF carrier?

Select	Answer
A	Frequency hopping
B	Binary phase-shift keying
C	Direct sequence
D	Phase compandored spread spectrum

42. - E9A10

Which of the following choices is a way to improve the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Install a good radial system
B	Reduce the diameter of the radiating element
C	Shorten the radiating element
D	Isolate the coax shield from ground

43. - E9B07

How does the total amount of radiation emitted by a directional gain antenna compare with the total amount of radiation emitted from an isotropic antenna, assuming each is driven by the same amount of power?

Select	Answer
A	They are the same
B	The total amount of radiation from the directional antenna is increased by the gain of the antenna
C	The radiation from the isotropic antenna is 2.15 dB stronger than that from the directional antenna
D	The total amount of radiation from the directional antenna is stronger by its front-to-back ratio

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	72 ohms
C	450 ohms
D	300 ohms

45. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase
B	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
C	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
D	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes

46. - E9E06

What is the equivalent lumped-constant network for a hairpin matching system of a 3-element Yagi?

Select	Answer
A	Pi-network
B	Pi-L-network
C	A series capacitor
D	A shunt inductor

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Antenna radiation pattern
B	Radio propagation
C	Radiation resistance
D	Impedance along transmission lines

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 is non-rotatable
C	It is practical for use only on VHF bands
D	It receives equally well in all directions

50. - E0A03

Which of the following would be a practical way to estimate whether the RF fields produced by an amateur radio station are within permissible MPE limits?

Select	Answer
A	Use an antenna modeling program to calculate field strength at accessible locations
B	All of the choices are correct
C	Use a calibrated antenna analyzer
D	Use a hand calculator plus Smith-chart equations to calculate the fields

Figure E5-2

Figure E7-1