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

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1. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Each transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded.
B	Only the most powerful transmitter
C	Each transmitter operating with a duty cycle greater than 50 percent
D	Only commercial transmitters

2. - E1A08

If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?

Select	Answer
A	The control operator of the originating station
B	The control operator of the packet bulletin board station
C	The control operators of all the stations in the system not authenticating the source from which they accept communications
D	The control operators of all the stations in the system

3. - E1B12

What must the control operator of a repeater operating in the 70 cm band do if a radiolocation system experiences interference from that repeater?

Select	Answer
A	All these choices are correct
B	File an FAA NOTAM (Notice to Airmen) with the repeater system's ERP, call sign, and six-character grid locator
C	Reduce the repeater antenna HAAT (Height Above Average Terrain)
D	Cease operation or make changes to the repeater to mitigate the interference

4. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	When approved by the National Telecommunication and Information Administration
B	When agreed upon by the sending or receiving station
C	Only when transmitting RTTY or data emissions
D	Never

5. - E1D12

Which of the following amateur stations may transmit one-way communications?

Select	Answer
A	A space station, beacon station, or telecommand station
B	All these choices are correct
C	A message forwarding station or automatically controlled digital station
D	A local repeater or linked repeater station

6. - E1E04

Which of the following best describes the Volunteer Examiner accreditation process?

Select	Answer
A	The prospective VE obtains accreditation from the FCC
B	The amateur operator applying must pass a VE examination administered by the FCC Enforcement Bureau
C	Each General, Advanced and Amateur Extra Class operator is automatically accredited as a VE when the license is granted
D	The procedure by which a VEC confirms that the VE applicant meets FCC requirements to serve as an examiner

7. - E1F04

Which of the following geographic descriptions approximately describes "Line A"?

Select	Answer
A	A line roughly parallel to and north of the border between the U.S. and Mexico
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and south of the border between the U.S. and Canada
D	A line roughly parallel to and west of the U.S. Atlantic coastline

8. - E2A07

Which of the following types of signals can be relayed through a linear transponder?

Select	Answer
A	FM and CW
B	All these choices are correct
C	PSK and packet
D	SSB and SSTV

9. - E2B01

How many times per second is a new frame transmitted in a fast-scan (NTSC) television system?

Select	Answer
A	30
B	90
C	120
D	60

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	In the middle of each band, usually on the national calling frequency
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	At the top of each band, usually in a segment reserved for contests

11. - E2D08

What type of packet frame is used to transmit APRS beacon data?

Select	Answer
A	Acknowledgement
B	Unnumbered Information
C	Connect
D	Disconnect

12. - E2E08

Which of the following HF digital modes can be used to transfer binary files?

Select	Answer
A	AMTOR
B	RTTY
C	Hellschreiber
D	PACTOR

13. - E3A11

What is a typical range for tropospheric propagation of microwave signals?

Select	Answer
A	10 miles to 50 miles
B	100 miles to 300 miles
C	2500 miles
D	1200 miles

14. - E3B06

Which of the following amateur bands most frequently provides long-path propagation?

Select	Answer
A	20 meters
B	6 meters
C	80 meters
D	10 meters

15. - E3C12

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

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

16. - E4A07

Which of the following is an advantage of using an antenna analyzer compared to an SWR bridge to measure antenna SWR?

Select	Answer
A	Antenna analyzers display a time-varying representation of the modulation envelope
B	All these choices are correct
C	Antenna analyzers do not need an external RF source
D	Antenna analyzers automatically tune your antenna for resonance

17. - E4B06

How much power is being absorbed by the load when a directional power meter connected between a transmitter and a terminating load reads 100 watts forward power and 25 watts reflected power?

Select	Answer
A	75 watts
B	100 watts
C	25 watts
D	125 watts

18. - E4C08

An SDR receiver is overloaded when input signals exceed what level?

Select	Answer
A	The reference voltage of the analog-to-digital converter
B	One-half the maximum sampling buffer size
C	One-half the maximum sample rate
D	The maximum count value of the analog-to-digital converter

19. - E4D11

Why are odd-order intermodulation products, created within a receiver, of particular interest compared to other products?

Select	Answer
A	Odd-order products of two signals in the band of interest are also likely to be within the band
B	Odd-order intermodulation produces three products for every input signal within the band of interest
C	Odd-order products are an indication of poor image rejection
D	Odd-order products overload the IF filters

20. - E4E02

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

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

21. - E5A01

What can cause the voltage across reactances in a series RLC circuit to be higher than the voltage applied to the entire circuit?

Select	Answer
A	Resonance
B	Resistance
C	Capacitance
D	Conductance

22. - 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 or to discharge to 36.8% of its initial voltage?

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

23. - E5C10

Which point on Figure E5-1 best represents the impedance of a series circuit consisting of a 400-ohm resistor and a 38-picofarad capacitor at 14 MHz?

Select	Answer
A	Point 6
B	Point 4
C	Point 2
D	Point 5

24. - E5D05

What is the power factor of an RL circuit having a 30-degree phase angle between the voltage and the current?

Select	Answer
A	0.577
B	1.73
C	0.866
D	0.5

25. - E6A01

In what application is gallium arsenide used as a semiconductor material?

Select	Answer
A	In microwave circuits
B	In high-power audio circuits
C	In high-current rectifier circuits
D	In very low-frequency RF circuits

26. - E6B08

Which of the following is a Schottky barrier diode?

Select	Answer
A	Metal-semiconductor junction
B	PIN junction
C	Thermionic emission diode
D	Electrolytic rectifier

27. - E6C08

In Figure E6-3, what is the schematic symbol for a NAND gate?

Select	Answer
A	1
B	2
C	4
D	3

28. - 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

29. - E6E05

Which of the following noise figure values is typical of a low-noise UHF preamplifier?

Select	Answer
A	2 dB
B	-10 dB
C	44 dBm
D	-20 dBm

30. - E6F02

What happens to the conductivity of a photoconductive material when light shines on it?

Select	Answer
A	It decreases
B	It becomes unstable
C	It increases
D	It stays the same

31. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It maintains a constant output voltage, regardless of variations in the input voltage
B	It switches momentarily to the opposite binary state and then returns to its original state after a set time
C	It produces a continuous square wave oscillating between 1 and 0
D	It stores one bit of data in either a 0 or 1 state

32. - E7B06

Which of the following amplifier types reduces even-order harmonics?

Select	Answer
A	Push-pull
B	Class AB
C	Class C
D	Push-push

33. - E7C08

Which of the following factors has the greatest effect on the bandwidth and response shape of a crystal ladder filter?

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

34. - E7D14

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

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

35. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a loop modulator followed by a mixer
B	By using a balanced modulator followed by a filter
C	By driving a product detector with a DSB signal
D	By using a reactance modulator followed by a mixer

36. - E7F08

What is the function of decimation?

Select	Answer
A	Reducing the effective sample rate by removing samples
B	Removing unnecessary significant digits
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 high
B	1000 ohms
C	Very low
D	100 ohms

38. - E7H10

What information is contained in the lookup table of a direct digital synthesizer (DDS)?

Select	Answer
A	Frequently used receiver and transmitter frequencies
B	The phase relationship between a voltage-controlled oscillator and the output waveform
C	The phase relationship between a reference oscillator and the output waveform
D	Amplitude values that represent the desired waveform

39. - E8A05

What of the following instruments would be the most accurate for measuring the RMS voltage of a complex waveform?

Select	Answer
A	A grid dip meter
B	An absorption wave meter
C	A true-RMS calculating meter
D	A D'Arsonval meter

40. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

Select	Answer
A	A frequency modulation technique that uses non-harmonically related frequencies
B	A bandwidth compression technique using Fourier transforms
C	A digital mode for narrow-band, slow-speed transmissions
D	A digital modulation technique using subcarriers at frequencies chosen to avoid intersymbol interference

41. - E8C10

How may data rate be increased without increasing bandwidth?

Select	Answer
A	Increasing analog-to-digital conversion resolution
B	Using forward error correction
C	Using a more efficient digital code
D	It is impossible

42. - E8D08

What parameter evaluates distortion of an AFSK signal caused by excessive input audio levels?

Select	Answer
A	Intermodulation Distortion (IMD)
B	Signal-to-noise ratio
C	Repeat Request Rate (RRR)
D	Baud rate

43. - E9A08

What is antenna bandwidth?

Select	Answer
A	The angle between the half-power radiation points
B	The frequency range over which an antenna satisfies a performance requirement
C	Antenna length divided by the number of elements
D	The angle formed between two imaginary lines drawn through the element ends

44. - E9B03

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

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

45. - E9C13

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with increasing height above ground?

Select	Answer
A	The takeoff angle of the lowest elevation lobe decreases
B	The horizontal beamwidth increases
C	The takeoff angle of the lowest elevation lobe increases
D	The horizontal beamwidth decreases

46. - E9D06

What happens to the SWR bandwidth when one or more loading coils are used to resonate an electrically short antenna?

Select	Answer
A	It is unchanged if the loading coil is located at a voltage maximum point
B	It is unchanged if the loading coil is located at the feed point
C	It is decreased
D	It is increased

47. - E9E06

Which of these feed line impedances would be suitable for constructing a quarter-wave Q-section for matching a 100-ohm loop to 50-ohm feed line?

Select	Answer
A	450 ohms
B	62 ohms
C	75 ohms
D	50 ohms

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	6.9 meters
B	8.3 meters
C	10.4 meters
D	5.2 meters

49. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning reactance values with regard to the resistance axis
B	Reassigning prime center with regard to the reactance axis
C	Reassigning resistance values with regard to the reactance axis
D	Reassigning impedance values with regard to the prime center

50. - E9H01

When constructing a Beverage antenna, which of the following factors should be included in the design to achieve good performance at the desired frequency?

Select	Answer
A	It must be mounted more than 1 wavelength above ground
B	It should be one or more wavelengths long
C	Its overall length must not exceed 1/4 wavelength
D	It should be configured as a four-sided loop

Figure E5-1

Figure E6-3

Figure E9-1