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

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1. - E0A11

Which of the following injuries can result from using high-power UHF or microwave transmitters?

Select	Answer
A	Ingestion of ozone gas from the cooling system
B	Localized heating of the body from RF exposure in excess of the MPE limits
C	Hearing loss caused by high voltage corona discharge
D	Blood clotting from the intense magnetic field

2. - E1A14

Except in some parts of Alaska, what is the maximum power permitted on the 630 meter band?

Select	Answer
A	100 watts PEP
B	50 watts PEP
C	5 watts EIRP
D	1 watt EIRP

3. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in Florida surrounding Cape Canaveral
B	An area in Puerto Rico surrounding the Arecibo Radio Telescope
C	An area surrounding the National Radio Astronomy Observatory
D	An area in New Mexico surrounding the White Sands Test Area

4. - E1C04

What is meant by IARP?

Select	Answer
A	The internal amateur radio practices policy of the FCC
B	A forecast of intermittent aurora radio propagation
C	An indication of increased antenna reflected power
D	An international amateur radio permit that allows U.S. amateurs to operate in certain countries of the Americas

5. - E1D06

What is the maximum permitted transmitter output power when operating a model craft by telecommand?

Select	Answer
A	100 watts
B	5 watts
C	1 watt
D	2 watts

6. - 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

7. - E1F01

On what frequencies are spread spectrum transmissions permitted?

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

8. - E2A10

What type of satellite appears to stay in one position in the sky?

Select	Answer
A	LEO
B	HEO
C	Geomagnetic
D	Geostationary

9. - E2B11

What is the function of the Vertical Interval Signaling (VIS) code sent as part of an SSTV transmission?

Select	Answer
A	To lock the color burst oscillator in color SSTV images
B	To identify the SSTV mode being used
C	To identify the call sign of the station transmitting
D	To provide vertical synchronization

10. - E2C06

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

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

11. - E2D09

What type of modulation is used for JT65 contacts?

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

12. - E2E10

Which of these digital modes has the narrowest bandwidth?

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

13. - E3A14

What is meant by circularly polarized electromagnetic waves?

Select	Answer
A	Waves produced by a loop antenna
B	Waves that circle the Earth
C	Waves with an electric field bent into a circular shape
D	Waves with a rotating electric field

14. - E3B03

What is the best time of day for transequatorial propagation?

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

15. - E3C11

What does VOACAP software model?

Select	Answer
A	VHF radio propagation
B	AC voltage and impedance
C	HF propagation
D	AC current and impedance

16. - E4A02

Which of the following parameters does a spectrum analyzer display on the vertical and horizontal axes?

Select	Answer
A	RF amplitude and frequency
B	SWR and time
C	SWR and frequency
D	RF amplitude and time

17. - E4B10

Which of the following methods measures intermodulation distortion in an SSB transmitter?

Select	Answer
A	Modulate the transmitter using two RF signals having harmonically related frequencies and observe the RF output with a logic analyzer
B	Modulate the transmitter using two AF signals having harmonically related frequencies and observe the RF output with a peak reading wattmeter
C	Modulate the transmitter using two RF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer
D	Modulate the transmitter using two AF signals having non-harmonically related frequencies and observe the RF output with a spectrum analyzer

18. - E4C10

What is an advantage of having a variety of receiver IF bandwidths from which to select?

Select	Answer
A	Receive bandwidth can be set to match the modulation bandwidth, maximizing signal-to-noise ratio and minimizing interference
B	Receiver power consumption can be reduced when wider bandwidth is not required
C	The noise figure of the RF amplifier can be adjusted to match the modulation type, thus increasing receiver sensitivity
D	Multiple frequencies can be received simultaneously if desired

19. - E4D07

Which of the following reduces the likelihood of receiver desensitization?

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

20. - E4E05

How can radio frequency interference from an AC motor be suppressed?

Select	Answer
A	By installing a bypass capacitor in series with the motor leads
B	By installing a high-pass filter in series with the motor's power leads
C	By using a ground-fault current interrupter in the circuit used to power the motor
D	By installing a brute-force AC-line filter in series with the motor leads

21. - E5A09

How is the Q of an RLC parallel resonant circuit calculated?

Select	Answer
A	Reactance of the inductance multiplied by the reactance of the capacitance
B	Reactance of either the inductance or capacitance divided by the resistance
C	Reactance of either the inductance or capacitance multiplied by the resistance
D	Resistance divided by the reactance of either the inductance or capacitance

22. - E5B09

What is the relationship between the AC current through a capacitor and the voltage across a capacitor?

Select	Answer
A	Current leads voltage by 90 degrees
B	Voltage and current are in phase
C	Voltage leads current by 90 degrees
D	Voltage and current are 180 degrees out of phase

23. - E5C07

Where is the impedance of a pure resistance plotted on rectangular coordinates?

Select	Answer
A	On a line through the origin, slanted at 45 degrees
B	On the vertical axis
C	On the horizontal axis
D	On a horizontal line, offset vertically above the horizontal axis

24. - E5D08

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	1000 watts
B	600 watts
C	1600 watts
D	200 watts

25. - E6A10

In Figure E6-1, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	6
C	2
D	4

26. - E6B10

In Figure E6-2, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	1
B	7
C	6
D	5

27. - E6C04

Which of the following is an advantage of BiCMOS logic?

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

28. - E6D01

Why should core saturation of an impedance matching transformer be avoided?

Select	Answer
A	Temporary changes of the core permeability could result
B	Magnetic flux would increase with frequency
C	RF susceptance would increase
D	Harmonics and distortion could result

29. - E6E10

What advantage does surface-mount technology offer at RF compared to using through-hole components?

Select	Answer
A	Shorter circuit-board traces
B	Smaller circuit area
C	All these choices are correct
D	Components have less parasitic inductance and capacitance

30. - E6F08

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

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

31. - E7A11

What type of logic defines "1" as a high voltage?

Select	Answer
A	Reverse Logic
B	Assertive Logic
C	Negative logic
D	Positive Logic

32. - E7B02

What is a Class D amplifier?

Select	Answer
A	An amplifier that uses drift-mode FETs for high efficiency
B	A frequency doubling amplifier
C	A type of amplifier that uses switching technology to achieve high efficiency
D	A low power amplifier that uses a differential amplifier for improved linearity

33. - E7C05

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

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

34. - 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 series current source
B	A shunt current source
C	A series regulator
D	A shunt regulator

35. - E7E10

How does a diode envelope detector function?

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

36. - E7F12

Which of the following is an advantage of a Finite Impulse Response (FIR) filter vs an Infinite Impulse Response (IIR) digital filter?

Select	Answer
A	FIR filters can respond faster to impulses
B	FIR filters are easier to implement for a given set of passband rolloff requirements
C	FIR filters can delay all frequency components of the signal by the same amount
D	All these choices are correct

37. - E7G09

What will be the output voltage of the circuit shown in Figure E7-3 if R1 is 1000 ohms, RF is 10,000 ohms, and 0.23 volts DC is applied to the input?

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

38. - E7H01

What are three oscillator circuits used in amateur radio equipment?

Select	Answer
A	Colpitts, Hartley and Pierce
B	Pierce, Fenner and Beane
C	Taft, Hartley and Pierce
D	Taft, Pierce and negative feedback

39. - E8A11

Which of the following is a measure of the quality of an analog-to-digital converter?

Select	Answer
A	Power factor
B	Peak envelope power
C	Total harmonic distortion
D	Reciprocal mixing

40. - E8B06

What is the deviation ratio of an FM-phone signal having a maximum frequency swing of plus or minus 7.5 kHz when the maximum modulation frequency is 3.5 kHz?

Select	Answer
A	0.214
B	2.14
C	0.47
D	47

41. - E8C08

How does ARQ accomplish error correction?

Select	Answer
A	If errors are detected, a retransmission is requested
B	Special binary codes provide automatic correction
C	Special polynomial codes provide automatic correction
D	If errors are detected, redundant data is substituted

42. - E8D11

What is one advantage of using ASCII code for data communications?

Select	Answer
A	It is possible to transmit both upper and lower case text
B	It includes built-in error correction features
C	It contains fewer information bits per character than any other code
D	It uses one character as a shift code to send numeric and special characters

43. - E9A07

What is the effective isotropic radiated power of a repeater station with 200 watts transmitter power output, 2 dB feed line loss, 2.8 dB duplexer loss, 1.2 dB circulator loss, and 7 dBi antenna gain?

Select	Answer
A	632 watts
B	159 watts
C	252 watts
D	63.2 watts

44. - E9B03

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

Select	Answer
A	24 dB
B	18 dB
C	12 dB
D	14 dB

45. - E9C09

Which of the following describes a G5RV antenna?

Select	Answer
A	A multi-band dipole antenna fed with coax and a balun through a selected length of open wire transmission line
B	A phased array antenna consisting of multiple loops
C	A multi-band trap antenna
D	A wide band dipole using shorted coaxial cable for the radiating elements and fed with a�4:1 balun

46. - E9D02

How can linearly polarized Yagi antennas be used to produce circular polarization?

Select	Answer
A	Arrange two Yagis perpendicular to each other with the driven elements at the same point on the boom fed 90 degrees out of phase
B	Stack two Yagis fed in phase to form an array with the respective elements in parallel planes
C	Stack two Yagis fed 90 degrees out of phase to form an array with the respective elements in parallel planes
D	Arrange two Yagis collinear to each other with the driven elements fed 180 degrees out of phase

47. - 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	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
B	Connect a 1/4-wavelength open stub of 300-ohm twinlead in parallel with the coaxial feed line where it connects to the antenna
C	Insert a 1/2 wavelength piece of 300-ohm twinlead in series between the antenna terminals and the 50-ohm feed cable
D	Connect a 1/2 wavelength shorted stub of 75-ohm cable in parallel with the 50-ohm cable where it attaches to the antenna

48. - E9F06

What is the approximate physical length of an air-insulated, parallel conductor transmission line that is electrically 1/2 wavelength long at 14.10 MHz?

Select	Answer
A	8.5 meters
B	10.6 meters
C	13.3 meters
D	7.0 meters

49. - E9G09

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

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

50. - E9H02

Which is generally true for low band (160 meter and 80 meter) receiving antennas?

Select	Answer
A	All these choices are correct
B	Low loss coax transmission line is essential for good performance
C	Atmospheric noise is so high that gain over a dipole is not important
D	They must be erected at least 1/2 wavelength above the ground to attain good directivity

Figure E6-1

Figure E6-2

Figure E7-3

Figure E9-1