US Amateur Radio - Amateur Extra (Element 4, 2020-2024) Practice Test

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1. - E0A03

Over what range of frequencies are the FCC human body RF exposure limits most restrictive?

Select	Answer
A	3 to 30 MHz
B	300 to 3000 MHz
C	30 to 300 MHz
D	300 kHz to 3 MHz

2. - E1A05

What is the maximum power output permitted on the 60 meter band?

Select	Answer
A	100 watts PEP effective radiated power relative to an isotropic radiator
B	50 watts PEP effective radiated power relative to a dipole
C	50 watts PEP effective radiated power relative to an isotropic radiator
D	100 watts PEP effective radiated power relative to the gain of a half-wave dipole

3. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historic Places?

Select	Answer
A	A form FSD-15 must be submitted to the Department of the Interior
B	An Environmental Assessment must be submitted to the FCC
C	A letter of intent must be filed with the Environmental Protection Agency
D	A proposal must be submitted to the National Park Service

4. - E1C13

What notifications must be given before transmitting on the 630 meter or 2200 meter bands?

Select	Answer
A	A special endorsement must be requested from the FCC
B	Operators must inform the FAA of their intent to operate, giving their call sign and distance to the nearest runway
C	An environmental impact statement must be filed with the Department of the Interior
D	Operators must inform the Utilities Technology Council (UTC) of their call sign and coordinates of the station

5. - E1D03

What is a space telecommand station?

Select	Answer
A	An amateur station that transmits communications to initiate, modify or terminate functions of a space station
B	An amateur station that receives telemetry from a satellite or balloon more than 50 kilometers above the surface of the Earth
C	An amateur station located in a satellite or a balloon more than 50 kilometers above the surface of the Earth
D	An amateur station located on the surface of the Earth for communication with other Earth stations by means of Earth satellites

6. - E1E07

What should a VE do if a candidate fails to comply with the examiner's instructions during an amateur operator license examination?

Select	Answer
A	Warn the candidate that continued failure to comply will result in termination of the examination
B	Allow the candidate to complete the examination, but invalidate the results
C	Immediately terminate everyone's examination and close the session
D	Immediately terminate the candidate's examination

7. - E1F08

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

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

8. - E2A05

What do the letters in a satellite's mode designator specify?

Select	Answer
A	The location of the ground control station
B	The uplink and downlink frequency ranges
C	Power limits for uplink and downlink transmissions
D	The polarization of uplink and downlink signals

9. - E2B09

What hardware, other than a receiver with SSB capability and a suitable computer, is needed to decode SSTV using Digital Radio Mondiale (DRM)?

Select	Answer
A	A special IF converter
B	No other hardware is needed
C	A special front end limiter
D	A special notch filter to remove synchronization pulses

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

11. - E2D09

What type of modulation is used for JT65 contacts?

Select	Answer
A	RTTY
B	IEEE 802.11
C	PSK
D	Multi-tone AFSK

12. - E2E07

Which of the following is a possible reason that attempts to initiate contact with a digital station on a clear frequency are unsuccessful?

Select	Answer
A	Your transmit frequency is incorrect
B	All these choices are correct
C	Another station you are unable to hear is using the frequency
D	The protocol version you are using is not supported by the digital station

13. - E3A06

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

14. - E3B07

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

Select	Answer
A	They become elliptically polarized
B	They become phase locked
C	They become depolarized
D	They are bent toward the magnetic poles

15. - 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	Transequatorial
B	Sporadic E
C	Polar
D	NVIS

16. - E4A08

Which of the following measures SWR?

Select	Answer
A	An ohmmeter
B	A spectrum analyzer
C	An antenna analyzer
D	A Q meter

17. - E4B11

Which of the following can be measured with a vector network analyzer?

Select	Answer
A	Reflection coefficient
B	Output impedance
C	All these choices are correct
D	Input impedance

18. - E4C04

What is the noise figure of a receiver?

Select	Answer
A	The ratio of thermal noise to atmospheric noise
B	The ratio of the noise bandwidth in hertz to the theoretical bandwidth of a resistive network
C	The ratio of atmospheric noise to phase noise
D	The ratio in dB of the noise generated by the receiver to the theoretical minimum noise

19. - 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 input signals will theoretically generate a third-order intermodulation product that has the same output amplitude as either of 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 that is 40 dB stronger than the input signal

20. - E4E02

Which of the following types of noise can often be reduced with a digital signal processing noise filter?

Select	Answer
A	Broadband white noise
B	Power line noise
C	Ignition noise
D	All these choices are correct

21. - E5A07

What is the magnitude of the current at the input of a parallel RLC circuit at resonance?

Select	Answer
A	R/L
B	Minimum
C	L/R
D	Maximum

22. - E5B07

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 500 ohms, R is 1 kilohm, and XL is 250 ohms?

Select	Answer
A	14.0 degrees with the voltage leading the current
B	68.2 degrees with the voltage lagging the current
C	68.2 degrees with the voltage leading the current
D	14.0 degrees with the voltage lagging the current

23. - E5C05

What is the name of the diagram used to show the phase relationship between impedances at a given frequency?

Select	Answer
A	Far field diagram
B	Phasor diagram
C	Near field diagram
D	Venn diagram

24. - E5D12

How many watts are consumed in a circuit having a power factor of 0.2 if the input is 100 VAC at 4 amperes?

Select	Answer
A	80 watts
B	50 watts
C	400 watts
D	2000 watts

25. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Insulator impurity
B	Donor impurity
C	Acceptor impurity
D	N-type impurity

26. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Charge carrier depletion
B	Excessive junction temperature
C	Excessive inverse voltage
D	Insufficient forward voltage

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

Select	Answer
A	Its simplicity results in much less expensive devices than standard CMOS
B	It is immune to electrostatic damage
C	All these choices are correct
D	It has the high input impedance of CMOS and the low output impedance of bipolar transistors

28. - E6D03

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

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

29. - E6E11

What is a characteristic of DIP packaging used for integrated circuits?

Select	Answer
A	Low leakage doubly insulated package
B	Two chips in each package (Dual In Package)
C	Package mounts in a direct inverted position
D	A total of two rows of connecting pins placed on opposite sides of the package (Dual In-line Package)

30. - E6F08

Why are optoisolators often used in conjunction with solid-state circuits when switching 120 VAC?

Select	Answer
A	Optoisolators provide a low impedance link between a control circuit and a power circuit
B	Optoisolators provide a very high degree of electrical isolation between a control circuit and the circuit being switched
C	Optoisolators provide impedance matching between the control circuit and power circuit
D	Optoisolators eliminate the effects of reflected light in the control circuit

31. - 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	Monostable multivibrator
C	Astable multivibrator
D	J-K flip-flop

32. - 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 adjusted to minimum plate current while alternately adjusting the tuning capacitor for maximum allowable plate current
B	The loading capacitor is set to maximum capacitance and the tuning capacitor is adjusted for minimum 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

33. - E7C07

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50-ohm unbalanced output?

Select	Answer
A	A network with only three discrete parts
B	A Pi-network with an additional series inductor on the output
C	A matching network in which all components are isolated from ground
D	A Phase Inverter Load network

34. - E7D14

What is the purpose of connecting equal-value resistors across power supply filter capacitors connected in series?

Select	Answer
A	All these choices are correct
B	Equalize the voltage across each capacitor
C	Discharge the capacitors when voltage is removed
D	Provide a minimum load on the supply

35. - E7E05

What circuit is added to an FM transmitter to boost the higher audio frequencies?

Select	Answer
A	A pre-emphasis network
B	A heterodyne enhancer
C	A heterodyne suppressor
D	A de-emphasis network

36. - E7F08

What is the function of decimation?

Select	Answer
A	Removing unnecessary significant digits
B	Reducing the effective sample rate by removing samples
C	Attenuating the signal
D	Converting data to binary code decimal form

37. - E7G03

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

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

38. - E7H09

What type of frequency synthesizer circuit uses a phase accumulator, lookup table, digital to analog converter, and a low-pass anti-alias filter?

Select	Answer
A	A diode-switching matrix synthesizer
B	A direct digital synthesizer
C	A hybrid synthesizer
D	A phase-locked loop synthesizer

39. - E8A09

How many different input levels can be encoded by an analog-to-digital converter with 8-bit resolution?

Select	Answer
A	256
B	8
C	8 multiplied by the gain of the input amplifier
D	256 divided by the gain of the input amplifier

40. - E8B04

What is the modulation index of an FM-phone signal having a maximum carrier deviation of plus or minus 6 kHz when modulated with a 2 kHz modulating frequency?

Select	Answer
A	1/3
B	2000
C	6000
D	3

41. - E8C06

What is the bandwidth of a 170-hertz shift, 300-baud ASCII transmission?

Select	Answer
A	0.5 kHz
B	0.3 kHz
C	1.0 kHz
D	0.1 Hz

42. - E8D02

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

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

43. - E9A10

Which of the following improves the efficiency of a ground-mounted quarter-wave vertical antenna?

Select	Answer
A	Shortening the radiating element
B	Isolating the coax shield from ground
C	Installing a radial system
D	All these choices are correct

44. - E9B10

What is the principle of a Method of Moments analysis?

Select	Answer
A	A wire is modeled as a single sine-wave current generator
B	A wire is modeled as a series of segments, each having a uniform value of current
C	A wire is modeled as a series of segments, each having a distinct value of voltage across it
D	A wire is modeled as a single sine-wave voltage source

45. - E9C06

What is the effect of adding a terminating resistor to a rhombic antenna?

Select	Answer
A	It decreases the ground loss
B	It changes the radiation pattern from horizontal to vertical polarization
C	It changes the radiation pattern from bidirectional to unidirectional
D	It reflects the standing waves on the antenna elements back to the transmitter

46. - E9D12

Which of the following would provide the best RF ground for your station?

Select	Answer
A	An electrically short connection to 3 or 4 interconnected ground rods driven into the Earth
B	An electrically short connection to 3 or 4 interconnected ground rods via a series RF choke
C	An electrically short connection to a metal water pipe
D	A 50-ohm resistor connected to ground

47. - E9E07

What parameter describes the interactions at the load end of a mismatched transmission line?

Select	Answer
A	Characteristic impedance
B	Velocity factor
C	Dielectric constant
D	Reflection coefficient

48. - E9F09

What is the approximate physical length of a foam polyethylene dielectric coaxial transmission line that is electrically 1/4 wavelength long at 7.2 MHz?

Select	Answer
A	5.2 meters
B	10.4 meters
C	8.3 meters
D	6.9 meters

49. - E9G07

On the Smith chart shown in Figure E9-3, what is the only straight line shown?

Select	Answer
A	The current axis
B	The resistance axis
C	The voltage axis
D	The reactance axis

50. - E9H04

What is an advantage of placing a grounded electrostatic shield around a small loop direction-finding antenna?

Select	Answer
A	It eliminates tracking errors caused by strong out-of-band signals
B	It increases signal strength by providing a better match to the feed line
C	It eliminates unbalanced capacitive coupling to the surroundings, improving the nulls
D	It adds capacitive loading, increasing the bandwidth of the antenna

Figure E9-3