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

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1. - E1A02

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the lowest frequency at which a properly adjusted LSB emission will be totally within the band?

Select	Answer
A	The exact lower band edge
B	300 Hz above the lower band edge
C	3 kHz above the lower band edge
D	1 kHz above the lower band edge

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 53 dB below
B	At least 73 dB below
C	At least 63 dB below
D	At least 43 dB below

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only earth stations, repeater stations or model craft
B	Only auxiliary, beacon or space stations
C	Only auxiliary, repeater or space stations
D	Only beacon, repeater or space stations

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	A fine of up to $1000 per occurrence
C	All of these choices are correct
D	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant

6. - E1F09

Which of the following conditions apply when transmitting spread spectrum emission?

Select	Answer
A	All of these choices are correct
B	A station transmitting SS emission must not cause harmful interference to other stations employing other authorized emissions
C	The transmission must not be used to obscure the meaning of any communication
D	The transmitting station must be in an area regulated by the FCC or in a country that permits SS emissions

7. - E2A02

What is the direction of a descending pass for an amateur satellite?

Select	Answer
A	From east to west
B	From south to north
C	From west to east
D	From north to south

8. - E2B04

What is blanking in a video signal?

Select	Answer
A	Turning off the scanning beam while it is traveling from right to left or from bottom to top
B	Turning off the scanning beam at the conclusion of a transmission
C	Transmitting a black and white test pattern
D	Synchronization of the horizontal and vertical sync pulses

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	2 m
B	33 cm
C	30 m
D	6 m

10. - E2D02

Which of the following is a good technique for making meteor scatter contacts?

Select	Answer
A	Use of high speed CW or digital modes
B	Short transmission with rapidly repeated call signs and signal reports
C	All of these choices are correct
D	15 second timed transmission sequences with stations alternating based on location

11. - E2E05

Which type of digital mode does not support keyboard-to-keyboard operation?

Select	Answer
A	RTTY
B	PSK31
C	Winlink
D	MFSK

12. - E3A02

What characterizes libration fading of an EME signal?

Select	Answer
A	The returning echo is several Hertz lower in frequency than the transmitted signal
B	A gradual loss of signal as the Sun rises
C	A fluttery irregular fading
D	A slow change in the pitch of the CW signal

13. - E3B08

What type of HF propagation is probably occurring if radio signals travel along the terminator between daylight and darkness?

Select	Answer
A	Long-path
B	Transequatorial
C	Gray-line
D	Sporadic-E

14. - E3C12

How does the maximum distance of ground-wave propagation change when the signal frequency is increased?

Select	Answer
A	It increases
B	It stays the same
C	It decreases
D	It peaks at roughly 14 MHz

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate
B	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
C	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
D	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
B	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit
C	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
D	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter

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

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Amplifier desensitization
B	Intermodulation interference
C	Adjacent channel interference
D	Neutralization

19. - E4E08

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

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

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	44.72 MHz
B	22.36 MHz
C	3.56 MHz
D	1.78 MHz

21. - E5B11

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 25 ohms, R is 100 ohms, and XL is 50 ohms?

Select	Answer
A	14 degrees with the voltage lagging the current
B	76 degrees with the voltage lagging the current
C	76 degrees with the voltage leading the current
D	14 degrees with the voltage leading the current

22. - E5C07

What is a vector?

Select	Answer
A	The inverse of the tangent function
B	The inverse of the sine function
C	A quantity with both magnitude and an angular component
D	The value of a quantity that changes over time

23. - E5D14

What is reactive power?

Select	Answer
A	Power consumed in circuit Q
B	Power lost because of capacitor leakage
C	Wattless, nonproductive power
D	Power consumed in wire resistance in an inductor

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	N-type
B	P-type
C	Bipolar
D	Insulated gate

25. - E6B09

What is a common use for point contact diodes?

Select	Answer
A	As a constant current source
B	As a constant voltage source
C	As a high voltage rectifier
D	As an RF detector

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	Input signals are stronger
C	Larger bypass capacitors are used in CMOS circuit design
D	The input switching threshold is about two times the power supply voltage

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores make it easier to couple the magnetic energy into other components
B	Toroidal cores confine most of the magnetic field within the core material
C	Toroidal cores have lower Q characteristics
D	Toroidal cores exhibit greater hysteresis

28. - E6E12

Why are high-power RF amplifier ICs and transistors sometimes mounted in ceramic packages?

Select	Answer
A	To provide a low-pass frequency response
B	Better dissipation of heat
C	Enhanced sensitivity to light
D	High-voltage insulating ability

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The tendency of a battery to discharge when used outside
B	The conversion of light to electrical energy
C	The conversion of voltage to current when exposed to light
D	The conversion of electrical energy to mechanical energy

30. - E7A05

Which of the following is a circuit that continuously alternates between two states without an external clock?

Select	Answer
A	T flip-flop
B	J-K flip-flop
C	Monostable multivibrator
D	Astable multivibrator

31. - E7B16

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

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

32. - E7C04

How does an impedance-matching circuit transform a complex impedance to a resistive impedance?

Select	Answer
A	It cancels the reactive part of the impedance and changes the resistive part to a desired value
B	It introduces negative resistance to cancel the resistive part of impedance
C	Network resistances are substituted for load resistances and reactances are matched to the resistances
D	It introduces transconductance to cancel the reactive part of impedance

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

Select	Answer
A	The control element duty cycle is proportional to the line or load conditions
B	It eliminates the need for a pass transistor
C	It has a ramp voltage as its output
D	The conduction of a control element is varied to maintain a constant output voltage

34. - E7E10

How does a diode detector function?

Select	Answer
A	By rectification and filtering of RF signals
B	By breakdown of the Zener voltage
C	By sensing the change of reactance in the diode with respect to frequency
D	By mixing signals with noise in the transition region of the diode

35. - E7F06

What is the minimum number of bits required for an analog-to-digital converter to sample a signal with a range of 1 volt at a resolution of 1 millivolt?

Select	Answer
A	10 bits
B	4 bits
C	8 bits
D	6 bits

36. - E7G07

What magnitude of voltage gain can be expected from the circuit in Figure E7-4 when R1 is 10 ohms and RF is 470 ohms?

Select	Answer
A	47
B	24
C	94
D	0.21

37. - E7H06

Which of the following oscillator circuits are commonly used in VFOs?

Select	Answer
A	Pierce and Zener
B	Negative feedback and balanced feedback
C	Armstrong and deForest
D	Colpitts and Hartley

38. - E8A11

What type of information can be conveyed using digital waveforms?

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

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	The transmitted signal jumps from band to band at a predetermined rate
C	Two or more information streams are merged into a baseband, which then modulates the transmitter
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C05

What is the necessary bandwidth of a 13-WPM international Morse code transmission?

Select	Answer
A	Approximately 13 Hz
B	Approximately 104 Hz
C	Approximately 26 Hz
D	Approximately 52 Hz

41. - E8D04

What is the primary effect of extremely short rise or fall time on a CW signal?

Select	Answer
A	More difficult to copy
B	The generation of RF harmonics
C	The generation of key clicks
D	Limits data speed

42. - E9A07

What is meant by antenna gain?

Select	Answer
A	The final amplifier gain minus the transmission line losses
B	The ratio of the signal in the forward direction to that in the opposite direction
C	The ratio of the amount of power radiated by an antenna compared to the transmitter output power
D	The ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Radiation resistance
B	Elevation
C	Polarization
D	Azimuth

44. - E9C04

What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?

Select	Answer
A	The vertical angle increases
B	The front-to-back ratio decreases
C	The lobes become more perpendicular to the wire
D	The lobes align more in the direction of the wire

45. - E9D01

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

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

46. - E9E13

What is a use for a Wilkinson divider?

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

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	The same as the input impedance to the final generator stage
B	A capacitive reactance
C	An inductive reactance
D	The same as the characteristic impedance of the line

48. - E9G09

What third family of circles is often added to a Smith chart during the process of solving problems?

Select	Answer
A	Coaxial-length circles
B	Standing wave ratio circles
C	Antenna-length circles
D	Radiation-pattern circles

49. - E9H10

How can the output voltage of a multiple turn receiving loop antenna be increased?

Select	Answer
A	By increasing either the number of wire turns in the loop or the area of the loop structure or both
B	By reducing the permeability of the loop shield
C	By increasing the number of wire turns in the loop and reducing the area of the loop structure
D	By winding adjacent turns in opposing 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	All of the choices are correct
B	Use a hand calculator plus Smith-chart equations to calculate the fields
C	Use an antenna modeling program to calculate field strength at accessible locations
D	Use a calibrated antenna analyzer

Figure E7-4

Figure E9-2