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

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1. - E1A03

With your transceiver displaying the carrier frequency of phone signals, you hear a station calling CQ on 14.349 MHz USB. Is it legal to return the call using upper sideband on the same frequency?

Select	Answer
A	No, the sideband will extend beyond the band edge
B	No, U.S. stations are not permitted to use phone emissions above 14.340 MHz
C	Yes, because the displayed frequency is within the 20 meter band
D	Yes, because you were not the station calling CQ

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	Military Auxiliary Radio System (MARS) channels
B	All amateur service frequencies authorized to the control operator
C	Specific local government channels
D	Specific segments in the amateur service MF, HF, VHF and UHF bands

3. - E1C06

Which of the following statements concerning remotely controlled amateur stations is true?

Select	Answer
A	Only Extra Class operators may be the control operator of a remote station
B	A control operator must be present at the control point
C	A control operator need not be present at the control point
D	Repeater and auxiliary stations may not be remotely controlled

4. - E1D06

Which of the following is a requirement of a space station?

Select	Answer
A	The space station must be capable of changing its orbit whenever such a change is ordered by NASA
B	All of these choices are correct
C	The space station must cease all transmissions after 5 years
D	The space station must be capable of terminating transmissions by telecommand when directed by the FCC

5. - E1E08

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

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

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

7. - E2A14

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

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

8. - E2B05

Which of the following is an advantage of using vestigial sideband for standard fast- scan TV transmissions?

Select	Answer
A	The vestigial sideband carries the audio information
B	The vestigial sideband contains chroma information
C	Vestigial sideband provides high frequency emphasis to sharpen the picture
D	Vestigial sideband reduces bandwidth while allowing for simple video detector circuitry

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

10. - E2D11

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

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

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	300-baud packet
B	PSK31
C	170 Hz shift, 45 baud RTTY
D	MFSK16

12. - E3A06

Which of the following is required for microwave propagation via rain scatter?

Select	Answer
A	Rain droplets must be within the E layer
B	The rain must be within radio range of both stations
C	All of these choices are correct
D	Rain droplets must be electrically charged

13. - E3B01

What is transequatorial propagation?

Select	Answer
A	Propagation between any two points located on the magnetic equator
B	Propagation between two mid-latitude points at approximately the same distance north and south of the magnetic equator
C	Propagation between two stations at the same latitude
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	Very low solar activity
D	Moderate solar wind

15. - E4A09

When using a computer's soundcard input to digitize signals, what is the highest frequency signal that can be digitized without aliasing?

Select	Answer
A	It depends on how the data is stored internally
B	One-half the sample rate
C	One-tenth the sample rate
D	The same as the sample rate

16. - E4B04

If a frequency counter with a specified accuracy of +/- 0.1 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	14.652 Hz
B	0.1 MHz
C	1.4652 Hz
D	1.4652 kHz

17. - E4C05

What does a value of -174 dBm/Hz represent with regard to the noise floor of a receiver?

Select	Answer
A	The noise figure of a 1 Hz bandwidth receiver
B	The galactic noise contribution to minimum detectable signal
C	The minimum detectable signal as a function of receive frequency
D	The theoretical noise at the input of a perfect receiver at room temperature

18. - E4D10

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

Select	Answer
A	Signals less than 40 dBm will not generate audible third-order intermodulation products
B	A pair of 40 dBm signals will theoretically generate a third-order intermodulation product with the same level as the input signals
C	The receiver can tolerate signals up to 40 dB above the noise floor without producing 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. - E4E14

What is one type of electrical interference that might be caused by the operation of a nearby personal computer?

Select	Answer
A	A whining type noise that continually pulses off and on
B	The appearance of unstable modulated or unmodulated signals at specific frequencies
C	A clicking noise at intervals of a few seconds
D	A loud AC hum in the audio output of your station receiver

20. - E5A12

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 3.7 MHz and a Q of 118?

Select	Answer
A	31.4 kHz
B	15.7 kHz
C	436.6 kHz
D	218.3 kHz

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

22. - E5C10

When using rectangular coordinates to graph the impedance of a circuit, what does the vertical axis represent?

Select	Answer
A	Reactive component
B	Resistive component
C	The sum of the reactive and resistive components
D	The difference between the resistive and reactive components

23. - E5D17

How many watts are consumed in a circuit having a power factor of 0.6 if the input is 200VAC at 5 amperes?

Select	Answer
A	200 watts
B	1600 watts
C	600 watts
D	1000 watts

24. - E6A12

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

Select	Answer
A	To reduce the chance of the gate insulation being punctured by static discharges or 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 protect the substrate from excessive voltages

25. - E6B03

What special type of diode is capable of both amplification and oscillation?

Select	Answer
A	Zener
B	Junction
C	Tunnel
D	Point contact

26. - E6C04

What is the primary advantage of tri-state logic?

Select	Answer
A	Low power consumption
B	High speed operation
C	Ability to connect many device outputs to a common bus
D	More efficient arithmetic operations

27. - E6D03

Which of the following is an aspect of the piezoelectric effect?

Select	Answer
A	Increased conductivity in the presence of light
B	Mechanical deformation of material by the application of a voltage
C	Mechanical deformation of material by the application of a magnetic field
D	Generation of electrical energy in the presence of light

28. - E6E02

Which of the following device packages is a through-hole type?

Select	Answer
A	SOT
B	PLCC
C	Ball grid array
D	DIP

29. - E6F07

What is a solid state relay?

Select	Answer
A	A passive delay line
B	A mechanical relay that latches in the on or off state each time it is pulsed
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A relay using transistors to drive the relay coil

30. - E7A01

Which is a bi-stable circuit?

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

31. - E7B09

Which of the following describes how the loading and tuning capacitors are to be adjusted when tuning a vacuum tube RF power amplifier that employs a Pi-network output circuit?

Select	Answer
A	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum allowable plate current
B	The loading capacitor is adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
C	The tuning capacitor is set to maximum capacitance and the loading capacitor is adjusted for minimum plate permissible current
D	The tuning capacitor is adjusted for minimum plate current, and the loading capacitor is adjusted for maximum permissible plate current

32. - E7C05

Which filter type is described as having ripple in the passband and a sharp cutoff?

Select	Answer
A	A passive op-amp filter
B	A Chebyshev filter
C	A Butterworth filter
D	An active LC filter

33. - E7D04

Which of the following types of linear voltage regulator usually make the most efficient use of the primary power source?

Select	Answer
A	A shunt regulator
B	A series regulator
C	A series current source
D	A shunt current source

34. - E7E01

Which of the following can be used to generate FM phone emissions?

Select	Answer
A	A balanced modulator on the audio amplifier
B	A balanced modulator on the oscillator
C	A reactance modulator on the oscillator
D	A reactance modulator on the final amplifier

35. - E7F13

What is the function of taps in a digital signal processing filter?

Select	Answer
A	To reduce excess signal pressure levels
B	Provide access for debugging software
C	Select the point at which baseband signals are generated
D	Provide incremental signal delays for filter algorithms

36. - E7G03

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

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

37. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Use of NP0 capacitors
B	Eliminating noise on the oscillator's power supply
C	Mechanically isolating the oscillator circuitry from its enclosure
D	Using the oscillator only for CW and digital signals

38. - E8A13

Which of these methods is commonly used to convert analog signals to digital signals?

Select	Answer
A	Sequential sampling
B	Harmonic regeneration
C	Level shifting
D	Phase reversal

39. - E8B07

Orthogonal Frequency Division Multiplexing is a technique used for which type of amateur communication?

Select	Answer
A	EME
B	Extremely low-power contacts
C	OFDM signals are not allowed on amateur bands
D	High speed digital modes

40. - E8C01

How is Forward Error Correction implemented?

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

41. - E8D01

Why are received spread spectrum signals resistant to interference?

Select	Answer
A	The high power used by a spread spectrum transmitter keeps its signal from being easily overpowered
B	If interference is detected by the receiver it will signal the transmitter to change frequencies
C	Signals not using the spread spectrum algorithm are suppressed in the receiver
D	The receiver is always equipped with a digital blanker

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

43. - E9B04

What may occur when a directional antenna is operated at different frequencies within the band for which it was designed?

Select	Answer
A	The gain may change depending on frequency
B	Feed point impedance may become negative
C	The E-field and H-field patterns may reverse
D	Element spacing limits could be exceeded

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

45. - E9D13

What usually occurs if a Yagi antenna is designed solely for maximum forward gain?

Select	Answer
A	The front-to-back ratio decreases
B	The front-to-back ratio increases
C	The SWR is reduced
D	The frequency response is widened over the whole frequency band

46. - E9E13

What is a use for a Wilkinson divider?

Select	Answer
A	It divides the operating frequency of a transmitter signal so it can be used on a lower frequency band
B	It is used to feed low-impedance loads from a high-impedance source
C	It is used to divide power equally between two 50 ohm loads while maintaining 50 ohm input impedance
D	It is used to feed high-impedance antennas from a low-impedance source

47. - E9F15

What impedance does a 1/2 wavelength transmission line present to a generator when the line is open at the far end?

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

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	Polar axis
B	Impedance axis
C	Prime axis
D	Reactance axis

49. - E9H06

What is the triangulation method of direction finding?

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

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 E9-3