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

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1. - E1A12

With your transceiver displaying the carrier frequency of CW signals, you hear a DX station's CQ on 3.500 MHz. Is it legal to return the call using CW on the same frequency?

Select	Answer
A	No, one of the sidebands of the CW signal will be out of the band
B	Yes, the DX station initiated the contact
C	Yes, the displayed frequency is within the 80 meter CW band segment
D	No, U.S. stations are not permitted to use CW emissions below 3.525 MHz

2. - E1B03

Within what distance must an amateur station protect an FCC monitoring facility from harmful interference?

Select	Answer
A	30 miles
B	3 miles
C	10 miles
D	1 mile

3. - E1C08

What is the maximum permissible duration of a remotely controlled station's transmissions if its control link malfunctions?

Select	Answer
A	30 seconds
B	10 minutes
C	3 minutes
D	5 minutes

4. - E1D07

Which amateur service HF bands have frequencies authorized for space stations?

Select	Answer
A	All HF bands
B	Only the 40 m, 30 m, 20 m, 15 m, 12 m and 10 m bands
C	Only the 40 m, 20 m, 17 m, 15 m, 12 m and 10 m bands
D	Only the 40 m, 20 m, 17 m, 15 m and 10 m bands

5. - E1E01

What is the minimum number of qualified VEs required to administer an Element 4 amateur operator license examination?

Select	Answer
A	2
B	3
C	4
D	5

6. - E1F04

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

Select	Answer
A	A line roughly parallel to and north of the U.S.-Mexican border and Gulf coastline
B	A line roughly parallel to and east of the U.S. Pacific coastline
C	A line roughly parallel to and west of the U.S. Atlantic coastline
D	A line roughly parallel to and south of the U.S.-Canadian border

7. - E2A03

What is the orbital period of an Earth satellite?

Select	Answer
A	The point of minimum height of a satellite's orbit
B	The time it takes for a satellite to travel from perigee to apogee
C	The time it takes for a satellite to complete one revolution around the Earth
D	The point of maximum height of a satellite's orbit

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

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

10. - E2D06

Which of the following describes a method of establishing EME contacts?

Select	Answer
A	Time synchronous transmissions alternately from each station
B	High speed CW identification to avoid fading
C	Judging optimum transmission times by monitoring beacons reflected from the Moon
D	Storing and forwarding digital messages

11. - E2E04

What is indicated when one of the ellipses in an FSK crossed-ellipse display suddenly disappears?

Select	Answer
A	Selective fading has occurred
B	The mark and space signal have been inverted
C	The receiver has drifted 5 kHz from the desired receive frequency
D	One of the signal filters is saturated

12. - E3A12

What is the cause of auroral activity?

Select	Answer
A	The interaction in the F2 layer between the solar wind and the Van Allen belt
B	A low sunspot level combined with tropospheric ducting
C	Meteor showers concentrated in the extreme northern and southern latitudes
D	The interaction in the E layer of charged particles from the Sun with the Earth's magnetic field

13. - E3B04

What is meant by the terms extraordinary and ordinary waves?

Select	Answer
A	Long path and short path waves
B	Independent waves created in the ionosphere that are elliptically polarized
C	Refracted rays and reflected waves
D	Extraordinary waves describe rare long skip propagation compared to ordinary waves which travel shorter distances

14. - E3C07

Which of the following descriptors indicates the greatest solar flare intensity?

Select	Answer
A	Class A
B	Class X
C	Class M
D	Class B

15. - E4A12

Which of the following procedures is an important precaution to follow when connecting a spectrum analyzer to a transmitter output?

Select	Answer
A	Use high quality double shielded coaxial cables to reduce signal losses
B	All of these choices are correct
C	Match the antenna to the load
D	Attenuate the transmitter output going to the spectrum analyzer

16. - E4B12

What is the significance of voltmeter sensitivity expressed in ohms per volt?

Select	Answer
A	When used as a galvanometer, the reading in volts multiplied by the ohms per volt rating will determine the power drawn by the device under test
B	When used as an ammeter, the full scale reading in amps divided by ohms per volt rating will determine the size of shunt needed
C	The full scale reading of the voltmeter multiplied by its ohms per volt rating will indicate the input impedance of the voltmeter
D	When used as an ohmmeter, the reading in ohms divided by the ohms per volt rating will determine the voltage applied to the circuit

17. - E4C13

How does a narrow-band roofing filter affect receiver performance?

Select	Answer
A	All of these choices are correct
B	It improves dynamic range by attenuating strong signals near the receive frequency
C	It improves sensitivity by reducing front end noise
D	It improves intelligibility by using low Q circuitry to reduce ringing

18. - E4D02

Which of the following describes two problems caused by poor dynamic range in a communications receiver?

Select	Answer
A	Oscillator instability and severe audio distortion of all but the strongest received signals
B	Cross-modulation of the desired signal and insufficient audio power to operate the speaker
C	Oscillator instability requiring frequent retuning and loss of ability to recover the opposite sideband
D	Cross-modulation of the desired signal and desensitization from strong adjacent signals

19. - E4E15

Which of the following can cause shielded cables to radiate or receive interference?

Select	Answer
A	Use of braided shielding material
B	Tying all ground connections to a common point resulting in differential mode currents in the shield
C	Low inductance ground connections at both ends of the shield
D	Common mode currents on the shield and conductors

20. - E5A07

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

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

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	One time constant
C	An exponential rate of one
D	A time factor of one

22. - E5C13

What coordinate system is often used to display the resistive, inductive, and/or capacitive reactance components of impedance?

Select	Answer
A	Rectangular coordinates
B	Maidenhead grid
C	Faraday grid
D	Elliptical coordinates

23. - E5D13

How much power is consumed in a circuit consisting of a 100 ohm resistor in series with a 100 ohm inductive reactance drawing 1 ampere?

Select	Answer
A	200 Watts
B	100 Watts
C	70.7 Watts
D	141.4 Watts

24. - E6A16

What are the majority charge carriers in N-type semiconductor material?

Select	Answer
A	Free neutrons
B	Free electrons
C	Holes
D	Free protons

25. - E6B02

What is an important characteristic of a Schottky diode as compared to an ordinary silicon diode when used as a power supply rectifier?

Select	Answer
A	Much higher reverse voltage breakdown
B	Less forward voltage drop
C	Controlled reverse avalanche voltage
D	Enhanced carrier retention time

26. - E6C01

What is the function of hysteresis in a comparator?

Select	Answer
A	To cause the output to change states continually
B	To increase the sensitivity
C	To allow the comparator to be used with AC input signal
D	To prevent input noise from causing unstable output signals

27. - 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	Butterworth filters
B	Steel-core toroids
C	Ferrite beads
D	Electrolytic capacitors

28. - E6E10

What is the packaging technique in which leadless components are soldered directly to circuit boards?

Select	Answer
A	Stripped lead
B	Virtual lead mounting
C	Surface mount
D	Direct soldering

29. - E6F07

What is a solid state relay?

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

30. - E7A12

What type of logic defines "0" as a high voltage?

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

31. - E7B14

Why are switching amplifiers more efficient than linear amplifiers?

Select	Answer
A	Switching amplifiers operate at higher voltages
B	Switching amplifiers use push-pull circuits
C	The power transistor is at saturation or cut off most of the time, resulting in low power dissipation
D	Linear amplifiers have high gain resulting in higher harmonic content

32. - E7C07

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

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

33. - E7D06

What is the purpose of Q1 in the circuit shown in Figure E7-3?

Select	Answer
A	It provides negative feedback to improve regulation
B	It provides a constant load for the voltage source
C	It increases the current-handling capability of the regulator
D	It provides D1 with current

34. - E7E09

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

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

35. - E7F14

Which of the following would allow a digital signal processing filter to create a sharper filter response?

Select	Answer
A	Double-precision math routines
B	Higher data rate
C	Complex phasor representations
D	More taps

36. - E7G04

What is meant by the term op-amp input offset voltage?

Select	Answer
A	The output voltage of the op-amp minus its input voltage
B	The difference between the output voltage of the op-amp and the input voltage required in the immediately following stage
C	The potential between the amplifier input terminals of the op-amp in an open loop condition
D	The differential input voltage needed to bring the open loop output voltage to zero

37. - E7H01

What are three oscillator circuits used in Amateur Radio equipment?

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

38. - E8A03

What type of wave does a Fourier analysis show to be made up of sine waves of a given fundamental frequency plus all of its harmonics?

Select	Answer
A	A square wave
B	A sine wave
C	A cosine wave
D	A sawtooth wave

39. - E8B01

What is the term for the ratio between the frequency deviation of an RF carrier wave and the modulating frequency of its corresponding FM-phone signal?

Select	Answer
A	Percentage of modulation
B	Quieting index
C	FM compressibility
D	Modulation index

40. - E8C09

Which is the name of a digital code where each preceding or following character changes by only one bit?

Select	Answer
A	Excess 3 code
B	Gray code
C	Extended Binary Coded Decimal Interchange Code
D	Binary Coded Decimal Code

41. - E8D12

What is the advantage of including a parity bit with an ASCII character stream?

Select	Answer
A	Foreign language characters can be sent
B	Some types of errors can be detected SUBELEMENT E9 - ANTENNAS AND TRANSMISSION LINES [8 Exam Questions - 8 Groups] E9A Basic Antenna parameters: radiation resistance, gain, beamwidth, efficiency, beamwidth; effective radiated power, polarization E9A01 (C) What describes an isotropic antenna? A. A grounded antenna used to measure earth conductivity B. A horizontally polarized antenna used to compare Yagi antennas C. A theoretical antenna used as a reference for antenna gain D. A spacecraft antenna used to direct signals toward the earth
C	Faster transmission rate
D	The signal can overpower interfering signals

42. - E9A07

What is meant by antenna gain?

Select	Answer
A	The final amplifier gain minus the transmission line losses
B	The ratio of the radiated signal strength of an antenna in the direction of maximum radiation to that of a reference antenna
C	The ratio of the amount of power radiated by an antenna compared to the transmitter output power
D	The ratio of the signal in the forward direction to that in the opposite direction

43. - E9B15

What is the front-to-back ratio of the radiation pattern shown in Figure E9-2?

Select	Answer
A	15 dB
B	24 dB
C	28 dB
D	3 dB

44. - E9C02

What is the radiation pattern of two 1/4 wavelength vertical antennas spaced 1/4 wavelength apart and fed 90 degrees out of phase?

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

45. - E9D06

What happens to the bandwidth of an antenna as it is shortened through the use of loading coils?

Select	Answer
A	No change occurs
B	It is decreased
C	It is increased
D	It becomes flat

46. - E9E09

Which of these matching systems is an effective method of connecting a 50 ohm coaxial cable feed line to a grounded tower so it can be used as a vertical antenna?

Select	Answer
A	All of these choices are correct
B	Gamma match
C	Double-bazooka match
D	Hairpin match

47. - E9F03

Why is the physical length of a coaxial cable transmission line shorter than its electrical length?

Select	Answer
A	The characteristic impedance is higher in a parallel feed line
B	The surge impedance is higher in a parallel feed line
C	Electrical signals move more slowly in a coaxial cable than in air
D	Skin effect is less pronounced in the coaxial cable

48. - E9G05

What type of chart is shown in Figure E9-3?

Select	Answer
A	Elevation angle radiation pattern chart
B	Azimuth angle radiation pattern chart
C	Free space radiation directivity chart
D	Smith chart

49. - E9H04

What is an advantage of using a shielded loop antenna for direction finding?

Select	Answer
A	It is electro statically balanced against ground, giving better nulls
B	It eliminates tracking errors caused by strong out-of-band signals
C	It automatically cancels ignition noise in mobile installations
D	It allows stations to communicate without giving away their position

50. - E0A07

How may dangerous levels of carbon monoxide from an emergency generator be detected?

Select	Answer
A	Any ordinary smoke detector can be used
B	By the yellowish appearance of the gas
C	By the odor
D	Only with a carbon monoxide detector

Figure E7-3

Figure E9-2

Figure E9-3