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 commercial transmitters
C	Only the most powerful transmitter
D	Each transmitter operating with a duty cycle greater than 50 percent

2. - E1A09

What action or actions should you take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	All these choices are correct
B	Notify the originating station that the communication does not comply with FCC rules
C	Discontinue forwarding the communication as soon as you become aware of it
D	Notify the nearest FCC Field Engineers office

3. - E1B06

Which of the following additional rules apply if you are installing an amateur station antenna at a site at or near a public use airport?

Select	Answer
A	You must file an Environmental Impact Statement with the EPA before construction begins
B	You may have to notify the Federal Aviation Administration and register it with the FCC as required by Part 17 of the FCC rules
C	You must obtain a construction permit from the airport zoning authority
D	You must submit engineering drawings to the FAA

4. - E1C01

What is the maximum bandwidth for a data emission on 60 meters?

Select	Answer
A	60 Hz
B	170 Hz
C	1.5 kHz
D	2.8 kHz

5. - E1D04

Which of the following is required in the identification transmissions from a balloon-borne telemetry station?

Select	Answer
A	Call sign
B	The output power of the balloon transmitter
C	All these choices are correct
D	The station's six-character Maidenhead grid locator

6. - E1E02

Who does Part 97 task with maintaining the pools of questions for all U.S. amateur license examinations?

Select	Answer
A	The ARRL
B	The FCC
C	The VEs
D	The VECs

7. - E1F10

Who may be the control operator of an auxiliary station?

Select	Answer
A	Only General, Advanced or Amateur Extra Class operators
B	Any licensed amateur operator
C	Only Technician, General, Advanced or Amateur Extra Class operators
D	Only Amateur Extra Class operators

8. - E2A01

What is the direction of an ascending pass for an amateur satellite?

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

9. - E2B08

What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70 cm band?

Select	Answer
A	Transmitting on channels shared with cable TV
B	Using converted satellite TV dishes
C	Using USB and demodulating the signal with a computer sound card
D	Transmitting on the abandoned TV channel 2

10. - E2C07

What is the Cabrillo format?

Select	Answer
A	A method of exchanging information during a contest QSO
B	The most common set of contest rules
C	The rules of order for meetings between contest sponsors
D	A standard for submission of electronic contest logs

11. - E2D10

How can an APRS station be used to help support a public service communications activity?

Select	Answer
A	An APRS station with a Global Positioning System unit can automatically transmit information to show a mobile station's position during the event
B	All these choices are correct
C	APRS stations with General Personnel Scanners can automatically relay the participant numbers and time as they pass the check points
D	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital

12. - E2E05

Which of these digital modes does not support keyboard-to-keyboard operation?

Select	Answer
A	PACTOR
B	MFSK
C	RTTY
D	PSK31

13. - E3A01

What is the approximate maximum separation measured along the surface of the Earth between two stations communicating by EME?

Select	Answer
A	5000 miles, if the moon is at perigee
B	500 miles, if the moon is at perigee
C	12,000 miles, if the moon is visible by both stations
D	2000 miles, if the moon is at apogee

14. - E3B11

At what time of day can sporadic E propagation occur?

Select	Answer
A	Only around sunset and sunrise
B	Only around sunset
C	Only in hours of darkness
D	Any time

15. - E3C11

What does VOACAP software model?

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

16. - E4A10

Which of the following displays multiple digital signal states simultaneously?

Select	Answer
A	Network analyzer
B	Logic analyzer
C	Modulation monitor
D	Bit error rate tester

17. - E4B01

Which of the following factors most affects the accuracy of a frequency counter?

Select	Answer
A	Time base accuracy
B	Decade divider accuracy
C	Temperature coefficient of the logic
D	Input attenuator accuracy

18. - E4C09

Which of the following choices is a good reason for selecting a high frequency for the design of the IF in a superheterodyne HF or VHF communications receiver?

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

19. - E4D03

How can intermodulation interference between two repeaters occur?

Select	Answer
A	When the signals from the transmitters are reflected in phase from airplanes passing overhead
B	When the repeaters are in close proximity and the signals cause feedback in the final amplifier of one or both transmitters
C	When the signals from the transmitters are reflected out of phase from airplanes passing overhead
D	When the repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters

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	All these choices are correct
C	Power line noise
D	Ignition noise

21. - E5A08

What is the phase relationship between the current through and the voltage across a series resonant circuit at resonance?

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

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. - E5C03

Which of the following represents an inductive reactance in polar coordinates?

Select	Answer
A	A positive phase angle
B	A negative magnitude
C	A positive magnitude
D	A negative phase angle

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	1600 watts
C	600 watts
D	200 watts

25. - E6A05

How does DC input impedance at the gate of a field-effect transistor compare with the DC input impedance of a bipolar transistor?

Select	Answer
A	An FET has higher input impedance
B	An FET has lower input impedance
C	They are both low impedance
D	They are both high impedance

26. - E6B04

What type of semiconductor device is designed for use as a voltage-controlled capacitor?

Select	Answer
A	Zener diode
B	Silicon-controlled rectifier
C	Tunnel diode
D	Varactor diode

27. - E6C03

What is tri-state logic?

Select	Answer
A	Proprietary logic devices manufactured by Tri-State Devices
B	Logic devices with 0, 1, and high-impedance output states
C	Logic devices that utilize ternary math
D	Low-power logic devices designed to operate at 3 volts

28. - E6D02

What is the equivalent circuit of a quartz crystal?

Select	Answer
A	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in parallel
B	Motional capacitance, motional inductance, loss resistance, and a capacitor representing electrode and stray capacitance all in series
C	Motional capacitance, motional inductance, and loss resistance in series, all in parallel with a shunt capacitor representing electrode and stray capacitance
D	Motional inductance and loss resistance in series, paralleled with motional capacitance and a capacitor representing electrode and stray capacitance

29. - E6E02

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

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

30. - E6F11

What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?

Select	Answer
A	12 V
B	0.1 V
C	1.5 V
D	0.5 V

31. - E7A09

What logical operation is performed by an exclusive NOR gate?

Select	Answer
A	It produces logic 1 at its output only if all inputs are logic 1
B	It produces logic 0 at its output only if all inputs are logic 0
C	It produces logic 0 at its output if only one input is logic 1
D	It produces logic 1 at its output if only one input is logic 1

32. - E7B05

What can be done to prevent unwanted oscillations in an RF power amplifier?

Select	Answer
A	Use a phase inverter in the output filter
B	Tune both the input and output for maximum power
C	Tune the stage for maximum SWR
D	Install parasitic suppressors and/or neutralize the stage

33. - E7C12

What is one advantage of a Pi-matching network over an L-matching network consisting of a single inductor and a single capacitor?

Select	Answer
A	The Q of Pi-networks can be controlled
B	Pi-networks provide balanced input and output
C	Pi-networks are more stable
D	L-networks cannot perform impedance transformation

34. - E7D09

What is the main reason to use a charge controller with a solar power system?

Select	Answer
A	Prevention of battery undercharge
B	Matching of day and night charge rates
C	Prevention of battery damage due to overcharge
D	Control of electrolyte levels during battery discharge

35. - E7E09

What occurs when an excessive amount of signal energy reaches a mixer circuit?

Select	Answer
A	A beat frequency is generated
B	Automatic limiting occurs
C	Mixer blanking occurs
D	Spurious mixer products are generated

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	All these choices are correct
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	FIR filters can respond faster to impulses

37. - E7G06

What is the gain-bandwidth of an operational amplifier?

Select	Answer
A	The frequency at which the amplifier's offset voltage is zero
B	The gain of the amplifier at a filter's cutoff frequency
C	The frequency at which the open-loop gain of the amplifier equals one
D	The maximum frequency for a filter circuit using that type of amplifier

38. - E7H07

How can an oscillator's microphonic responses be reduced?

Select	Answer
A	Reduce noise on the oscillator's power supply
B	Increase the bias voltage
C	Use NP0 capacitors
D	Mechanically isolate the oscillator circuitry from its enclosure

39. - E8A02

Which of the following is a type of analog-to-digital conversion?

Select	Answer
A	Successive approximation
B	Harmonic regeneration
C	Phase reversal
D	Level shifting

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	47
D	0.47

41. - E8C08

How does ARQ accomplish error correction?

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

42. - E8D01

Why are received spread spectrum signals resistant to interference?

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

43. - E9A13

What term describes station output, taking into account all gains and losses?

Select	Answer
A	Half-power bandwidth
B	Apparent power
C	Effective radiated power
D	Power factor

44. - E9B04

What is the front-to-back ratio of the radiation pattern shown in Figure E92?

Select	Answer
A	15 dB
B	3 dB
C	38 dB
D	28 dB

45. - E9C07

What is the approximate feed point impedance at the center of a two-wire folded dipole antenna?

Select	Answer
A	450 ohms
B	50 ohms
C	72 ohms
D	300 ohms

46. - E9D11

Which of the following conductors would be best for minimizing losses in a station's RF ground system?

Select	Answer
A	Solid wire
B	Stranded wire
C	Wide flat copper strap
D	Resistive wire, such as spark plug wire

47. - E9E07

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

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

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	7.0 meters
B	8.5 meters
C	10.6 meters
D	13.3 meters

49. - E9G10

What do the arcs on a Smith chart represent?

Select	Answer
A	Points with constant resistance
B	Points with constant reactance
C	SWR
D	Frequency

50. - E9H09

What is a Pennant antenna?

Select	Answer
A	A four-element, high-gain vertical array invented by George Pennant
B	A stealth antenna built to look like a flagpole
C	A small, vertically oriented receiving antenna consisting of a triangular loop terminated in approximately 900 ohms
D	A form of rhombic antenna terminated in a variable capacitor to provide frequency diversity