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

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1. - E1A14

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	60 Hz
B	1.5 kHz
C	170 Hz
D	2.8 kHz

2. - E1B09

Which amateur stations may be operated under RACES rules?

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

3. - E1C03

How do the control operator responsibilities of a station under automatic control differ from one under local control?

Select	Answer
A	Under automatic control the control operator is not required to be present at the control point
B	Under local control a control operator is not required to be present at a control point
C	Under automatic control there is no control operator
D	Under local control there is no control operator

4. - E1D05

What class of licensee is authorized to be the control operator of a space station?

Select	Answer
A	Any class with appropriate operator privileges
B	Only General, Advanced or Amateur Extra Class
C	Only Amateur Extra Class
D	All except Technician Class

5. - E1E08

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

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

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	The equipment dealer assembled it from a kit
D	It was imported from a manufacturer in another country and was certificated by that country's government

7. - E2A04

What is meant by the term mode as applied to an amateur radio satellite?

Select	Answer
A	The satellite's orientation with respect to the Earth
B	The type of signals that can be relayed through the satellite
C	The satellite's uplink and downlink frequency bands
D	Whether the satellite is in a polar or equatorial orbit

8. - E2B07

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

Select	Answer
A	Luminance
B	Chroma
C	Hue
D	Spectral Intensity

9. - E2C11

How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?

Select	Answer
A	Send the call sign of the DX station three times, the words "this is", then your call sign three times
B	Send your full call sign and grid square
C	Send only the last two letters of your call sign until you make contact
D	Send your full call sign once or twice

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Time and frequency
B	Radio direction finding spectrum analysis
C	Polar coordinates
D	Latitude and longitude

11. - E2E12

Which type of control is used by stations using the Automatic Link Enable (ALE) protocol?

Select	Answer
A	Remote
B	Automatic
C	Local
D	ALE can use any type of control

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is full
B	When the Moon is at perigee
C	When the Moon is at apogee
D	When the MUF is above 30 MHz

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	Their polarization is randomly modified
B	They become phase-locked
C	They are bent toward the magnetic poles
D	They become elliptically polarized

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class B
B	Class A
C	Class X
D	Class M

15. - E4A03

Which of the following test instrument is used to display spurious signals and/or intermodulation distortion products in an SSB transmitter?

Select	Answer
A	A spectrum analyzer
B	A time-domain reflectometer
C	A wattmeter
D	A logic 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	Improved receiver noise figure
B	Easier for front-end circuitry to eliminate image responses
C	Reduced drift
D	Fewer components in the receiver

18. - E4D10

What does a third-order intercept level of 40 dBm mean with respect to receiver performance?

Select	Answer
A	A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
B	The receiver can tolerate signals up to 40 dB above the noise floor without producing third-order intermodulation products
C	Signals less than 40 dBm will not generate audible third-order intermodulation products
D	A pair of 1 mW input signals will produce a third-order intermodulation product which is 40 dB stronger than the input signal

19. - E4E13

What might be the cause of a loud roaring or buzzing AC line interference that comes and goes at intervals?

Select	Answer
A	Arcing contacts in a thermostatically controlled device
B	All of these choices are correct
C	A defective doorbell or doorbell transformer inside a nearby residence
D	A malfunctioning illuminated advertising display

20. - E5A16

What is the resonant frequency of a parallel RLC circuit if R is 33 ohms, L is 50 microhenrys and C is 10 picofarads?

Select	Answer
A	7.12 kHz
B	23.5 MHz
C	23.5 kHz
D	7.12 MHz

21. - E5B01

What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the applied voltage?

Select	Answer
A	A time factor of one
B	One time constant
C	An exponential rate of one
D	One exponential period

22. - E5C16

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor and a 19 picofarad capacitor at 21.200 MHz?

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

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

24. - E6A12

Why do many MOSFET devices have internally connected Zener diodes on the gates?

Select	Answer
A	To protect the substrate from excessive voltages
B	To keep the gate voltage within specifications and prevent the device from overheating
C	To provide a voltage reference for the correct amount of reverse-bias gate voltage
D	To reduce the chance of the gate insulation being punctured by static discharges or excessive voltages

25. - E6B13

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

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

26. - E6C10

In Figure E6-5, what is the schematic symbol for a NOR gate?

Select	Answer
A	3
B	4
C	2
D	1

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	Butterworth filters
C	Electrolytic capacitors
D	Steel-core toroids

28. - E6E03

Which of the following materials is likely to provide the highest frequency of operation when used in MMICs?

Select	Answer
A	Gallium nitride
B	Silicon nitride
C	Silicon
D	Silicon dioxide

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A frequency-determining unit for a transmitter or receiver
B	A display that uses a glowing liquid to remain brightly lit in dim light
C	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
D	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It produces a continuous square wave oscillating between 1 and 0
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 stores one bit of data in either a 0 or 1 state

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

Select	Answer
A	Low efficiency
B	Creation of parasitic oscillations
C	Transmission of spurious signals
D	All of these choices are correct

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

33. - E7D15

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

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

34. - E7E07

What is meant by the term baseband in radio communications?

Select	Answer
A	The lowest frequency band that the transmitter or receiver covers
B	The frequency components present in the modulating signal
C	The basic oscillator frequency in an FM transmitter that is multiplied to increase the deviation and carrier frequency
D	The unmodulated bandwidth of the transmitted signal

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

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	-0.23 volts
D	-2.3 volts

37. - E7H15

Which of these functions can be performed by a phase-locked loop?

Select	Answer
A	Comparison of two digital input signals, digital pulse counter
B	Photovoltaic conversion, optical coupling
C	Frequency synthesis, FM demodulation
D	Wide-band AF and RF power amplification

38. - E8A01

What is the name of the process that shows that a square wave is made up of a sine wave plus all of its odd harmonics?

Select	Answer
A	Fourier analysis
B	Differential analysis
C	Numerical analysis
D	Vector analysis

39. - E8B09

What is meant by deviation ratio?

Select	Answer
A	The ratio of the audio modulating frequency to the center carrier frequency
B	The ratio of the maximum carrier frequency deviation to the highest audio modulating frequency
C	The ratio of the carrier center frequency to the audio modulating 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	Baud is only used for RTTY
B	Baud is twice the symbol rate
C	Symbol rate is only used for packet-based modes
D	They are the same

41. - E8D06

Which of the following indicates likely overmodulation of an AFSK signal such as PSK or MFSK?

Select	Answer
A	Strong ALC action
B	Harmonics on higher bands
C	Rapid signal fading
D	High reflected power

42. - E9A02

What antenna has no gain in any direction?

Select	Answer
A	Yagi
B	Isotropic antenna
C	Quarter-wave vertical
D	Half-wave dipole

43. - E9B02

In the antenna radiation pattern shown in Figure E9-1, what is the front-to-back ratio?

Select	Answer
A	24 dB
B	36 dB
C	14 dB
D	18 dB

44. - E9C03

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced a 1/2 wavelength apart and fed in phase?

Select	Answer
A	A Figure-8 broadside to the axis of the array
B	A Figure-8 end-fire along the axis of the array
C	Cardioid
D	Omni-directional

45. - E9D10

What happens to feed point impedance at the base of a fixed length HF mobile antenna as the frequency of operation is lowered?

Select	Answer
A	The radiation resistance increases and the capacitive reactance increases
B	The radiation resistance decreases and the capacitive reactance increases
C	The radiation resistance increases and the capacitive reactance decreases
D	The radiation resistance decreases and the capacitive reactance decreases

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The omega matching system
B	The gamma matching system
C	The stub matching system
D	The delta matching system

47. - E9F04

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

Select	Answer
A	0.66
B	0.10
C	0.30
D	2.70

48. - E9G04

What are the two families of circles and arcs that make up a Smith chart?

Select	Answer
A	Resistance and reactance
B	Resistance and voltage
C	Reactance and voltage
D	Voltage and impedance

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	A very sharp peak
B	High-radiation angle
C	A very sharp single null
D	Broad band response

50. - E0A05

What is one of the potential hazards of using microwaves in the amateur radio bands?

Select	Answer
A	The high gain antennas commonly used can result in high exposure levels
B	Microwaves are ionizing radiation
C	Microwaves often travel long distances by ionospheric reflection
D	The extremely high frequency energy can damage the joints of antenna structures

Figure E5-2

Figure E6-5

Figure E7-4

Figure E9-1