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

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1. - E1A01

When using a transceiver that displays the carrier frequency of phone signals, which of the following displayed frequencies represents the highest frequency at which a properly adjusted USB emission will be totally within the band?

Select	Answer
A	The exact upper band edge
B	3 kHz below the upper band edge
C	300 Hz below the upper band edge
D	1 kHz below the upper band edge

2. - E1B10

What frequencies are authorized to an amateur station operating under RACES rules?

Select	Answer
A	All amateur service frequencies authorized to the control operator
B	Specific segments in the amateur service MF, HF, VHF and UHF bands
C	Specific local government channels
D	Military Auxiliary Radio System (MARS) channels

3. - E1C09

Which of these ranges of frequencies is available for an automatically controlled repeater operating below 30 MHz?

Select	Answer
A	29.500 MHz - 29.700 MHz
B	10.100 MHz - 10.150 MHz
C	18.110 MHz - 18.168 MHz
D	24.940 MHz - 24.990 MHz

4. - E1D07

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

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

5. - E1E08

To which of the following examinees may a VE not administer an examination?

Select	Answer
A	Employees of the VE
B	Friends of the VE
C	Relatives of the VE as listed in the FCC rules
D	All of these choices are correct

6. - E1F03

Under what circumstances may a dealer sell an external RF power amplifier capable of operation below 144 MHz if it has not been granted FCC certification?

Select	Answer
A	The equipment dealer assembled it from a kit
B	It was imported from a manufacturer in a country that does not require certification of RF power amplifiers
C	It was purchased in used condition from an amateur operator and is sold to another amateur operator for use at that operator's station
D	It was imported from a manufacturer in another country and was certificated by that country's government

7. - E2A12

What is one way to predict the location of a satellite at a given time?

Select	Answer
A	By means of the Doppler data for the specified satellite
B	By subtracting the mean anomaly from the orbital inclination
C	By calculations using the Keplerian elements for the specified satellite
D	By adding the mean anomaly to the orbital inclination

8. - E2B12

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

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

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 once or twice
C	Send only the last two letters of your call sign until you make contact
D	Send your full call sign and grid square

10. - E2D10

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

Select	Answer
A	An APRS station with an emergency medical technician can automatically transmit medical data to the nearest hospital
B	All of 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 a GPS unit can automatically transmit information to show a mobile station's position during the event

11. - E2E02

What do the letters FEC mean as they relate to digital operation?

Select	Answer
A	Fatal Error Correction
B	Final Error Correction
C	Forward Error Correction
D	First Error Correction

12. - E3A03

When scheduling EME contacts, which of these conditions will generally result in the least path loss?

Select	Answer
A	When the Moon is full
B	When the Moon is at apogee
C	When the MUF is above 30 MHz
D	When the Moon is at perigee

13. - E3B02

What is the approximate maximum range for signals using transequatorial propagation?

Select	Answer
A	5000 miles
B	2500 miles
C	7500 miles
D	1000 miles

14. - E3C09

How does the intensity of an X3 flare compare to that of an X2 flare?

Select	Answer
A	10 percent greater
B	50 percent greater
C	Four times as great
D	Twice as great

15. - E4A10

Which of the following displays multiple digital signal states simultaneously?

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

16. - E4B16

Which S parameter represents return loss or SWR?

Select	Answer
A	S12
B	S11
C	S22
D	S21

17. - E4C10

Which of the following is a desirable amount of selectivity for an amateur RTTY HF receiver?

Select	Answer
A	300 Hz
B	2400 Hz
C	6000 Hz
D	100 Hz

18. - E4D03

How can intermodulation interference between two repeaters occur?

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

19. - E4E03

Which of the following signals might a receiver noise blanker be able to remove from desired signals?

Select	Answer
A	Signals which appear across a wide bandwidth
B	Signals which have a sharply peaked frequency distribution
C	Signals which are constant at all IF levels
D	Signals which appear at one IF but not another

20. - E5A11

What is the half-power bandwidth of a parallel resonant circuit that has a resonant frequency of 7.1 MHz and a Q of 150?

Select	Answer
A	157.8 Hz
B	47.3 kHz
C	23.67 kHz
D	315.6 Hz

21. - E5B04

What is the time constant of a circuit having two 220 microfarad capacitors and two 1 megohm resistors, all in parallel?

Select	Answer
A	55 seconds
B	220 seconds
C	440 seconds
D	110 seconds

22. - E5C04

Which of the following represents a capacitive reactance in polar coordinates?

Select	Answer
A	A negative phase angle
B	A positive phase angle
C	A negative real part
D	A positive real part

23. - E5D03

What is microstrip?

Select	Answer
A	Precision printed circuit conductors above a ground plane that provide constant impedance interconnects at microwave frequencies
B	Short lengths of coax mounted on printed circuit boards to minimize time delay between microwave circuits
C	Lightweight transmission line made of common zip cord
D	Miniature coax used for low power applications

24. - E6A03

Why does a PN-junction diode not conduct current when reverse biased?

Select	Answer
A	Only N-type semiconductor material can conduct current
B	Only P-type semiconductor material can conduct current
C	Holes in P-type material and electrons in the N-type material are separated by the applied voltage, widening the depletion region
D	Excess holes in P-type material combine with the electrons in N-type material, converting the entire diode into an insulator

25. - E6B01

What is the most useful characteristic of a Zener diode?

Select	Answer
A	An internal capacitance that varies with the applied voltage
B	A negative resistance region
C	A constant voltage drop under conditions of varying current
D	A constant current drop under conditions of varying voltage

26. - E6C01

What is the function of hysteresis in a comparator?

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

27. - E6D01

How many turns will be required to produce a 5-microhenry inductor using a powdered-iron toroidal core that has an inductance index (A L) value of 40 microhenrys/100 turns?

Select	Answer
A	141 turns
B	79 turns
C	35 turns
D	13 turns

28. - E6E07

Which of the following is typically used to construct a MMIC-based microwave amplifier?

Select	Answer
A	Point-to-point construction
B	Ground-plane construction
C	Wave-soldering construction
D	Microstrip construction

29. - E6F12

What absorbs the energy from light falling on a photovoltaic cell?

Select	Answer
A	Holes
B	Protons
C	Electrons
D	Photons

30. - E7A07

What logical operation does a NAND gate perform?

Select	Answer
A	It produces logic "0" at its output only when all inputs are logic "1"
B	It produces logic "0" at its output if some but not all inputs are logic "1"
C	It produces logic "0" at its output only when all inputs are logic "0"
D	It produces logic "1" at its output only when all inputs are logic "1"

31. - E7B08

How can an RF power amplifier be neutralized?

Select	Answer
A	By feeding an in-phase component of the output back to the input
B	By feeding a 180-degree out-of-phase portion of the output back to the input
C	By reducing the driving power
D	By increasing the driving power

32. - E7C03

What advantage does a Pi-L-network have over a regular Pi-network for impedance matching between the final amplifier of a vacuum-tube transmitter and an antenna?

Select	Answer
A	Greater harmonic suppression
B	Greater transformation range
C	Lower losses
D	Higher efficiency

33. - E7D13

What is the equation for calculating power dissipation by a series connected linear voltage regulator?

Select	Answer
A	Voltage difference from input to output multiplied by output current
B	Input voltage divided by output current
C	Output voltage multiplied by output current
D	Input voltage multiplied by input current

34. - E7E06

Why is de-emphasis commonly used in FM communications receivers?

Select	Answer
A	For compatibility with transmitters using phase modulation
B	To reduce impulse noise reception
C	To remove third-order distortion products
D	For higher efficiency

35. - E7F11

What sets the minimum detectable signal level for an SDR in the absence of atmospheric or thermal noise?

Select	Answer
A	Reference voltage level and sample width in bits
B	Data storage transfer rate
C	Missing codes and jitter
D	Sample clock phase noise

36. - E7G12

What is an integrated circuit operational amplifier?

Select	Answer
A	An amplifier used to increase the average output of frequency modulated amateur signals to the legal limit
B	A digital audio amplifier whose characteristics are determined by components external to the amplifier
C	A RF amplifier used in the UHF and microwave regions
D	A high-gain, direct-coupled differential amplifier with very high input impedance and very low output impedance

37. - E7H08

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

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

38. - E8A02

What type of wave has a rise time significantly faster than its fall time (or vice versa)?

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

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	3000
B	0.3
C	1000
D	3

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	Binary Coded Decimal Code
D	Extended Binary Coded Decimal Interchange Code

41. - E8D08

What parameter might indicate that excessively high input levels are causing distortion in an AFSK signal?

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

42. - E9A18

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

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

43. - E9B08

How can the approximate beam-width in a given plane of a directional antenna be determined?

Select	Answer
A	Draw two imaginary lines through the ends of the elements and measure the angle between the lines
B	Measure the ratio of the signal strengths of the radiated power lobes from the front and rear of the antenna
C	Measure the ratio of the signal strengths of the radiated power lobes from the front and side of the antenna
D	Note the two points where the signal strength of the antenna is 3 dB less than maximum and compute the angular difference

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

45. - E9D01

How does the gain of an ideal parabolic dish antenna change when the operating frequency is doubled?

Select	Answer
A	Gain is multiplied by 0.707
B	Gain increases by 3 dB
C	Gain increases by 6 dB
D	Gain does not change

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

47. - E9F16

Which of the following is a significant difference between foam dielectric coaxial cable and solid dielectric cable, assuming all other parameters are the same?

Select	Answer
A	All of these choices are correct
B	Foam dielectric has lower safe operating voltage limits
C	Foam dielectric has higher velocity factor
D	Foam dielectric has lower loss per unit of length

48. - E9G01

Which of the following can be calculated using a Smith chart?

Select	Answer
A	Impedance along transmission lines
B	Radiation resistance
C	Radio propagation
D	Antenna radiation pattern

49. - E9H02

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

Select	Answer
A	They must be erected at least 1/2 wavelength above the ground to attain good directivity
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	All of these choices are correct

50. - E0A07

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

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