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

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1. - E1A05

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

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

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)
B	Only those club stations licensed to Amateur Extra class operators
C	Any FCC-licensed amateur station except a Technician class
D	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served

3. - E1C07

What is meant by local control?

Select	Answer
A	Controlling a station through a local auxiliary link
B	Controlling a repeater using a portable handheld transceiver
C	Direct manipulation of the transmitter by a control operator
D	Automatically manipulating local station controls

4. - E1D02

What is the amateur satellite service?

Select	Answer
A	A radio communications service using stations on Earth satellites for public service broadcast
B	A radio navigation service using satellites for the purpose of self training, intercommunication and technical studies carried out by amateurs
C	A radio communications service using amateur radio stations on satellites
D	A spacecraft launching service for amateur-built satellites

5. - E1E14

For which types of out-of-pocket expenses do the Part 97 rules state that VEs and VECs may be reimbursed?

Select	Answer
A	No expenses are authorized for reimbursement
B	Teaching an amateur operator license examination preparation course
C	Preparing, processing, administering and coordinating an examination for an amateur radio license
D	Providing amateur operator license examination preparation training materials

6. - E1F07

When may an amateur station send a message to a business?

Select	Answer
A	When neither the amateur nor his or her employer has a pecuniary interest in the communications
B	When transmitting international third-party communications
C	When the control operator is employed by the FCC or another government agency
D	When the total money involved does not exceed $25

7. - E2A01

What is the direction of an ascending 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. - E2B12

How are analog SSTV images typically transmitted on the HF bands?

Select	Answer
A	Varying tone frequencies representing the video are transmitted using PSK
B	Video is converted to equivalent Baudot representation
C	Varying tone frequencies representing the video are transmitted using single sideband
D	Video is converted to equivalent ASCII representation

9. - E2C09

What type of equipment is commonly used to implement a ham radio mesh network?

Select	Answer
A	An optical cable connection between the USB ports of 2 separate computers
B	A standard wireless router running custom software
C	A 440 MHz transceiver with a 9600 baud modem
D	A 2 meter VHF transceiver with a 1200 baud modem

10. - E2D04

What is the purpose of digital store-and-forward functions on an Amateur Radio satellite?

Select	Answer
A	To delay download of telemetry between satellites
B	To upload operational software for the transponder
C	To relay messages between satellites
D	To store digital messages in the satellite for later download by other stations

11. - E2E09

Which of the following HF digital modes uses variable-length coding for bandwidth efficiency?

Select	Answer
A	RTTY
B	PSK31
C	PACTOR
D	MT63

12. - E3A15

What is an electromagnetic wave?

Select	Answer
A	A wave consisting of an electric field and a magnetic field oscillating at right angles to each other
B	A wave consisting of two magnetic fields at right angles to each other
C	A wave consisting of two electric fields at parallel right angles to each other
D	A wave of alternating current, in the core of an electromagnet

13. - E3B08

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

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

14. - E3C11

What does VOACAP software model?

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

15. - E4A06

What is the effect of aliasing in a digital or computer-based oscilloscope?

Select	Answer
A	False triggering occurs
B	Calibration of the vertical scale is no longer valid
C	All signals will have a DC offset
D	False signals are displayed

16. - E4B14

What happens if a dip meter is too tightly coupled to a tuned circuit being checked?

Select	Answer
A	Cross modulation occurs
B	A less accurate reading results
C	Intermodulation distortion occurs
D	Harmonics are generated

17. - E4C04

How is the noise figure of a receiver defined?

Select	Answer
A	The ratio in dB of the noise generated by the receiver to the theoretical minimum 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 of thermal noise to atmospheric noise

18. - E4D11

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

Select	Answer
A	The third-order product of two signals which are in the band of interest is also likely to be within the band
B	Third-order intermodulation produces three products for every input signal within the band of interest
C	Third-order products are an indication of poor image rejection
D	The third-order intercept is much higher than other orders

19. - E4E09

What undesirable effect can occur when using an IF noise blanker?

Select	Answer
A	The audio frequency bandwidth of the received signal might be compressed
B	FM signals can no longer be demodulated
C	Received audio in the speech range might have an echo effect
D	Nearby signals may appear to be excessively wide even if they meet emission standards

20. - 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 and current are 180 degrees out of phase
B	The voltage leads the current by 90 degrees
C	The current leads the voltage by 90 degrees
D	The voltage and current are in phase

21. - 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?

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

22. - E5C12

If you plot the impedance of a circuit using the rectangular coordinate system and find the impedance point falls on the right side of the graph on the horizontal axis, what do you know about the circuit?

Select	Answer
A	It is equivalent to a pure resistance
B	It has to be a direct current circuit
C	It contains resistance and inductive reactance
D	It contains resistance and capacitive reactance

23. - 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	2000 watts
D	400 watts

24. - E6A10

In Figure E6-2, what is the schematic symbol for an N-channel dual-gate MOSFET?

Select	Answer
A	5
B	4
C	6
D	2

25. - E6B05

What characteristic of a PIN diode makes it useful as an RF switch or attenuator?

Select	Answer
A	Ability to dissipate large amounts of power
B	A large region of intrinsic material
C	Reverse bias controls its forward voltage drop
D	Extremely high reverse breakdown voltage

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Lower power consumption
B	Differential output capability
C	Immune to damage from static discharge
D	Lower distortion

27. - E6D11

How many turns will be required to produce a 1-mH inductor using a core that has an inductance index (A L) value of 523 millihenrys/1000 turns?

Select	Answer
A	229 turns
B	2 turns
C	43 turns
D	4 turns

28. - E6E05

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

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

29. - E6F07

What is a solid state relay?

Select	Answer
A	A relay using transistors to drive the relay coil
B	A mechanical relay that latches in the on or off state each time it is pulsed
C	A device that uses semiconductors to implement the functions of an electromechanical relay
D	A passive delay line

30. - E7A08

What logical operation does an OR gate perform?

Select	Answer
A	It only produces logic "0" at its output when all inputs are logic "1"
B	It produces logic "1" at its output if any or all inputs are logic "1"
C	It produces logic "1" at its output if all inputs are logic "0"
D	It produces logic "0" at its output if all inputs are logic "1"

31. - E7B12

What type of amplifier circuit is shown in Figure E7-1?

Select	Answer
A	Emitter follower
B	Common base
C	Common emitter
D	Common collector

32. - E7C07

What kind of filter would you use to attenuate an interfering carrier signal while receiving an SSB transmission?

Select	Answer
A	A Pi-network filter
B	A band-pass filter
C	An all-pass filter
D	A notch filter

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

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

34. - E7E11

Which type of detector is used for demodulating SSB signals?

Select	Answer
A	Phase comparator
B	Discriminator
C	Product detector
D	Phase detector

35. - E7F05

How frequently must an analog signal be sampled by an analog-to-digital converter so that the signal can be accurately reproduced?

Select	Answer
A	At four times the rate of the highest frequency component of the signal
B	At the same rate as the highest frequency component of the signal
C	At half the rate of the highest frequency component of the signal
D	At twice the rate of the highest frequency component of the signal

36. - E7G03

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

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

37. - E7H08

Which of the following components can be used to reduce thermal drift in crystal oscillators?

Select	Answer
A	Toroidal inductors
B	NP0 capacitors
C	Non-inductive resistors
D	Wirewound resistors

38. - E8A10

What is the purpose of a low pass filter used in conjunction with a digital-to-analog converter?

Select	Answer
A	Improve accuracy by removing out of sequence codes from the input
B	Lower the input bandwidth to increase the effective resolution
C	Remove harmonics from the output caused by the discrete analog levels generated
D	All of these choices are correct

39. - E8B03

What is the modulation index of an FM-phone signal having a maximum frequency deviation of 3000 Hz either side of the carrier frequency when the modulating frequency is 1000 Hz?

Select	Answer
A	0.3
B	1000
C	3000
D	3

40. - E8C02

What is the definition of symbol rate in a digital transmission?

Select	Answer
A	The number of control characters in a message packet
B	The number of characters carried per second by the station-to-station link
C	The duration of each bit in a message sent over the air
D	The rate at which the waveform of a transmitted signal changes to convey information

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

Select	Answer
A	If interference is detected by the receiver it will signal the transmitter to change frequencies
B	A pseudo-random binary bit stream is used to shift the phase of an RF carrier very rapidly in a particular sequence
C	The frequency of the transmitted signal is changed very rapidly according to a particular sequence also used by the receiving station
D	If interference is detected by the receiver it will signal the transmitter to wait until the frequency is clear

42. - E9A09

How is antenna efficiency calculated?

Select	Answer
A	(radiation resistance / transmission resistance) x 100 per cent
B	(radiation resistance / total resistance) x 100 per cent
C	(effective radiated power / transmitter output) x 100 percent
D	(total resistance / radiation resistance) x 100 per cent

43. - E9B12

What is the far field of an antenna?

Select	Answer
A	The region where radiated field strengths are obstructed by objects of reflection
B	The region of the ionosphere where radiated power is not refracted
C	The region where radiated power dissipates over a specified time period
D	The region where the shape of the antenna pattern is independent of distance

44. - E9C01

What is the radiation pattern of two 1/4-wavelength vertical antennas spaced 1/2-wavelength apart and fed 180 degrees out of phase?

Select	Answer
A	A figure-8 broadside to the axis of the array
B	Omni-directional
C	Cardioid
D	A figure-8 oriented along the axis of the array

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	Near the center of the vertical radiator
B	As close to the transmitter as possible
C	As low as possible on the vertical radiator
D	At a voltage node

46. - E9E03

What is the name of the matching system that uses a section of transmission line connected in parallel with the feed line at or near the feed point?

Select	Answer
A	The delta match
B	The omega match
C	The stub match
D	The gamma match

47. - E9F13

What impedance does a 1/4 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	Very high impedance
B	The same as the generator output impedance
C	Very low impedance
D	The same as the characteristic impedance of the transmission line

48. - E9G09

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

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

49. - E9H11

What characteristic of a cardioid pattern antenna is useful for direction finding?

Select	Answer
A	A very sharp peak
B	A very sharp single null
C	High-radiation angle
D	Broad band response

50. - E0A02

When evaluating RF exposure levels from your station at a neighbor's home, what must you do?

Select	Answer
A	Make sure signals from your station are less than the controlled MPE limits
B	You need only evaluate exposure levels on your own property
C	Make sure signals from your station are less than the uncontrolled MPE limits
D	Advise your neighbors of the results of your tests

Figure E6-2

Figure E7-1