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 must have a power supply that is completely independent of the main ship or aircraft power supply
C	The amateur operator must have an FCC Marine or Aircraft endorsement on his or her amateur license
D	The amateur station operator must agree not to transmit when the main radio of the ship or aircraft is in use

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station except a Technician class
B	Only those club stations licensed to Amateur Extra class operators
C	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
D	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	18.110 MHz - 18.168 MHz
B	29.500 MHz - 29.700 MHz
C	10.100 MHz - 10.150 MHz
D	24.940 MHz - 24.990 MHz

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A spacecraft launching service for amateur-built satellites
B	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
C	A radio communications service using amateur radio stations on satellites
D	A radio communications service using stations on Earth satellites for public service broadcast

5. - E1E11

What must the VE team do if an examinee scores a passing grade on all examination elements needed for an upgrade or new license?

Select	Answer
A	Photocopy all examination documents and forward them to the FCC for processing
B	All these choices are correct
C	Issue the examinee the new or upgrade license
D	Three VEs must certify that the examinee is qualified for the license grant and that they have complied with the administering VE requirements

6. - E1F01

On what frequencies are spread spectrum transmissions permitted?

Select	Answer
A	Only on amateur frequencies above 222 MHz
B	Only on amateur frequencies above 144 MHz
C	Only on amateur frequencies above 50 MHz
D	Only on amateur frequencies above 420 MHz

7. - E2A14

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

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

8. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	120
B	60
C	30
D	90

9. - E2C06

During a VHF/UHF contest, in which band segment would you expect to find the highest level of activity?

Select	Answer
A	In the middle of each band, usually on the national calling frequency
B	In the middle of the band, usually 25 kHz above the national calling frequency
C	At the top of each band, usually in a segment reserved for contests
D	In the weak signal segment of the band, with most of the activity near the calling frequency

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To upload operational software for the transponder
B	To store digital messages in the satellite for later download by other stations
C	To relay messages between satellites
D	To delay download of telemetry between satellites

11. - E2E06

What is the most common data rate used for HF packet?

Select	Answer
A	1200 baud
B	48 baud
C	110 baud
D	300 baud

12. - E3A16

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

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

13. - E3B03

What is the best time of day for transequatorial propagation?

Select	Answer
A	Afternoon or early evening
B	Morning
C	Noon
D	Late at night

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Increased transequatorial propagation likely
B	A meteor ping
C	Long-path propagation is occurring
D	A solar flare has occurred

15. - E4A11

Which of the following is good practice when using an oscilloscope probe?

Select	Answer
A	Keep the signal ground connection of the probe as short as possible
B	All of these choices are correct
C	Never use a high impedance probe to measure a low impedance circuit
D	Never use a DC-coupled probe to measure an AC circuit

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	146.52 Hz
B	165.2 Hz
C	14.652 kHz
D	1.4652 MHz

17. - E4C03

What is the term for the blocking of one FM phone signal by another, stronger FM phone signal?

Select	Answer
A	Cross-modulation interference
B	Frequency discrimination
C	Capture effect
D	Desensitization

18. - E4D14

Which of the following is a way to reduce the likelihood of receiver desensitization?

Select	Answer
A	Increase the receiver front end gain
B	Switch from fast AGC to slow AGC
C	Decrease the RF bandwidth of the receiver
D	Raise the receiver IF frequency

19. - E4E16

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

Select	Answer
A	Differential-mode current
B	Common-mode current
C	Reactive current only
D	Return 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	Low, as compared to the circuit resistance
B	Approximately equal to circuit resistance
C	Approximately equal to capacitive reactance
D	Approximately equal to inductive reactance

21. - E5B06

What is susceptance?

Select	Answer
A	The ratio of magnetic field to electric field
B	The inverse of reactance
C	A measure of the efficiency of a transformer
D	The magnetic impedance of a circuit

22. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A negative real part
B	A positive phase angle
C	A positive real part
D	A negative phase angle

23. - E5D03

What is microstrip?

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

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	Any FET without a channel
B	An FET that exhibits a current flow between source and drain when no gate voltage is applied
C	Any FET for which holes are the majority carriers
D	An FET that has no current flow between source and drain when no gate voltage is applied

25. - E6B13

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

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

26. - E6C06

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

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

27. - E6D09

What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?

Select	Answer
A	Ferrite beads
B	Electrolytic capacitors
C	Steel-core toroids
D	Butterworth filters

28. - E6E09

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

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

29. - E6F03

What is the most common configuration of an optoisolator or optocoupler?

Select	Answer
A	A frequency modulated helium-neon laser
B	A lens and a photomultiplier
C	An LED and a phototransistor
D	An amplitude modulated helium-neon laser

30. - E7A03

Which of the following can divide the frequency of a pulse train by 2?

Select	Answer
A	A flip-flop
B	An XOR gate
C	An OR gate
D	A multiplexer

31. - E7B03

Which of the following components form the output of a class D amplifier circuit?

Select	Answer
A	A temperature compensating load resistor to improve linearity
B	A high-pass filter to compensate for low gain at low frequencies
C	A low-pass filter to remove switching signal components
D	A matched load resistor to prevent damage by switching transients

32. - E7C08

Which of the following factors has the greatest effect in helping determine the bandwidth and response shape of a crystal ladder filter?

Select	Answer
A	The amplitude of the signals passing through the filter
B	The DC voltage applied to the quartz crystal
C	The gain of the RF stage preceding the filter
D	The relative frequencies of the individual crystals

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Linear voltage regulator
B	Grounded emitter amplifier
C	Emitter follower
D	Switching voltage regulator

34. - E7E11

Which type of detector is used for demodulating SSB signals?

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

35. - E7F16

How might the sampling rate of an existing digital signal be adjusted by a factor of 3/4?

Select	Answer
A	Add 3 to each input value and subtract 4 from each output value
B	Interpolate by a factor of three, then decimate by a factor of four
C	Multiply each sample value by a factor of 3/4
D	Change the gain by a factor of 3/4

36. - E7G09

What will be the output voltage of the circuit shown in Figure E7-4 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

Select	Answer
A	0.23 volts
B	-2.3 volts
C	2.3 volts
D	-0.23 volts

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A11

What type of information can be conveyed using digital waveforms?

Select	Answer
A	All of these choices are correct
B	Data
C	Video signals
D	Human speech

39. - E8B11

What is digital time division multiplexing?

Select	Answer
A	Two or more signals are quadrature modulated to increase bandwidth efficiency
B	Two or more data streams are assigned to discrete sub-carriers on an FM transmitter
C	Two or more data streams share the same channel by transmitting time of transmission as the sub-carrier
D	Two or more signals are arranged to share discrete time slots of a data transmission

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The duration of each bit in a message sent over the air
B	The number of characters carried per second by the station-to-station link
C	The number of control characters in a message packet
D	The rate at which the waveform of a transmitted signal changes to convey information

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	Intermodulation Distortion (IMD)
C	Signal to noise ratio
D	Baud rate

42. - E9A18

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Apparent power
B	Effective radiated power
C	Half-power bandwidth
D	Power factor

43. - E9B16

How many elevation lobes appear in the forward direction of the antenna radiation pattern shown in Figure E9-2?

Select	Answer
A	1
B	4
C	3
D	7

44. - E9C08

What is a folded dipole antenna?

Select	Answer
A	A type of ground-plane antenna
B	A dipole configured to provide forward gain
C	A dipole consisting of one wavelength of wire forming a very thin loop
D	A dipole one-quarter wavelength long

45. - E9D07

What is an advantage of using top loading in a shortened HF vertical antenna?

Select	Answer
A	Improved radiation efficiency
B	Greater structural strength
C	Higher losses
D	Lower Q

46. - E9E10

Which of these choices is an effective way to match an antenna with a 100 ohm feed point impedance to a 50 ohm coaxial cable feed line?

Select	Answer
A	Connect a 1/4-wavelength open stub of 300 ohm twin-lead in parallel with the coaxial feed line where it connects to the antenna
B	Insert a 1/2 wavelength piece of 300 ohm twin-lead in series between the antenna terminals and the 50 ohm feed cable
C	Connect 1/2 wavelength shorted stub of 75 ohm cable in parallel with the 50 ohm cable where it attaches to the antenna
D	Insert a 1/4-wavelength piece of 75 ohm coaxial cable transmission line in series between the antenna terminals and the 50 ohm feed cable

47. - E9F02

Which of the following determines the velocity factor of a transmission line?

Select	Answer
A	The termination impedance
B	Dielectric materials used in the line
C	The center conductor resistivity
D	The line length

48. - E9G06

On the Smith chart shown in Figure E9-3, what is the name for the large outer circle on which the reactance arcs terminate?

Select	Answer
A	Impedance axis
B	Prime axis
C	Reactance axis
D	Polar axis

49. - E9H09

Which of the following describes the construction of a receiving loop antenna?

Select	Answer
A	A large circularly polarized antenna
B	A vertical antenna coupled to a feed line through an inductive loop of wire
C	One or more turns of wire wound in the shape of a large open coil
D	A small coil of wire tightly wound around a toroidal ferrite core

50. - E0A08

What does SAR measure?

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

Figure E7-3

Figure E7-4

Figure E9-2

Figure E9-3