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

2. - E1B04

What must be done before placing an amateur station within an officially designated wilderness area or wildlife preserve, or an area listed in the National Register of Historical Places?

Select	Answer
A	A letter of intent must be filed with the National Audubon Society
B	A form FSD-15 must be submitted to the Department of the Interior
C	A proposal must be submitted to the National Park Service
D	An Environmental Assessment must be submitted to the FCC

3. - E1C08

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

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

4. - E1D08

Which VHF amateur service bands have frequencies available for space stations?

Select	Answer
A	2 meters and 1.25 meters
B	2 meters
C	6 meters and 2 meters
D	6 meters, 2 meters, and 1.25 meters

5. - E1E09

What may be the penalty for a VE who fraudulently administers or certifies an examination?

Select	Answer
A	A sentence of up to one year in prison
B	Revocation of the VE's amateur station license grant and the suspension of the VE's amateur operator license grant
C	A fine of up to $1000 per occurrence
D	All of these choices are correct

6. - E1F04

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

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

7. - E2A06

On what band would a satellite receive signals if it were operating in mode U/V?

Select	Answer
A	50.0 MHz - 50.2 MHz
B	435 MHz - 438 MHz
C	29.5 MHz - 29.7 MHz
D	144 MHz - 146 MHz

8. - E2B19

What special operating frequency restrictions are imposed on slow scan TV transmissions?

Select	Answer
A	None; they are allowed on all amateur frequencies
B	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz
C	They are restricted to phone band segments and their bandwidth can be no greater than that of a voice signal of the same modulation type
D	They are not permitted above 54 MHz

9. - E2C03

From which of the following bands is amateur radio contesting generally excluded?

Select	Answer
A	33 cm
B	2 m
C	30 m
D	6 m

10. - E2D11

Which of the following data are used by the APRS network to communicate your location?

Select	Answer
A	Time and frequency
B	Latitude and longitude
C	Polar coordinates
D	Radio direction finding spectrum analysis

11. - E2E11

What is the difference between direct FSK and audio FSK?

Select	Answer
A	Direct FSK uses a DC-coupled data connection
B	Audio FSK has a superior frequency response
C	Audio FSK can be performed anywhere in the transmit chain
D	Direct FSK applies the data signal to the transmitter VFO

12. - E3A11

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

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

13. - E3B02

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

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

14. - E3C13

What type of polarization is best for ground-wave propagation?

Select	Answer
A	Elliptical
B	Circular
C	Horizontal
D	Vertical

15. - E4A05

What might be an advantage of a digital vs an analog oscilloscope?

Select	Answer
A	All of these choices are correct
B	Manipulation of time base after trace capture
C	Storage of traces for future reference
D	Automatic amplitude and frequency numerical readout

16. - E4B01

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

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

17. - E4C10

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

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

18. - 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 repeaters are in close proximity and the signals mix in the final amplifier of one or both transmitters
D	When the signals from the transmitters are reflected out of phase from airplanes passing overhead

19. - E4E10

What is a common characteristic of interference caused by a touch controlled electrical device?

Select	Answer
A	The interfering signal may drift slowly across the HF spectrum
B	The interfering signal sounds like AC hum on an AM receiver or a carrier modulated by 60 Hz hum on a SSB or CW receiver
C	The interfering signal can be several kHz in width and usually repeats at regular intervals across a HF band
D	All of these choices are correct

20. - E5A10

How is the Q of an RLC series resonant circuit calculated?

Select	Answer
A	Resistance divided by the reactance of either the inductance or capacitance
B	Reactance of either the inductance or capacitance divided by the resistance
C	Reactance of the inductance times the reactance of the capacitance
D	Reactance of either the inductance or capacitance times the resistance

21. - E5B08

What is the phase angle between the voltage across and the current through a series RLC circuit if XC is 100 ohms, R is 100 ohms, and XL is 75 ohms?

Select	Answer
A	76 degrees with the voltage leading the current
B	76 degrees with the voltage lagging the current
C	14 degrees with the voltage lagging the current
D	14 degrees with the voltage leading the current

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

23. - E5D17

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	1600 watts
B	200 watts
C	1000 watts
D	600 watts

24. - E6A10

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

Select	Answer
A	6
B	4
C	2
D	5

25. - E6B13

What type of bias is required for an LED to emit light?

Select	Answer
A	Forward bias
B	Reverse bias
C	Inductive bias
D	Zero bias

26. - E6C06

Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?

Select	Answer
A	The input switching threshold is about two times the power supply voltage
B	Input signals are stronger
C	The input switching threshold is about one-half the power supply voltage
D	Larger bypass capacitors are used in CMOS circuit design

27. - E6D15

What is current in the primary winding of a transformer called if no load is attached to the secondary?

Select	Answer
A	Excitation current
B	Stabilizing current
C	Direct current
D	Magnetizing current

28. - E6E10

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

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

29. - E6F09

What is the efficiency of a photovoltaic cell?

Select	Answer
A	The output RF power divided by the input DC power
B	The relative fraction of light that is converted to current
C	The effective payback period
D	The open-circuit voltage divided by the short-circuit current under full illumination

30. - E7A02

What is the function of a decade counter digital IC?

Select	Answer
A	It produces one output pulse for every ten input pulses
B	It produces ten output pulses for every input pulse
C	It adds two decimal numbers together
D	It decodes a decimal number for display on a seven segment LED display

31. - E7B15

What is one way to prevent thermal runaway in a bipolar transistor amplifier?

Select	Answer
A	Use a resistor in series with the emitter
B	Neutralization
C	All of these choices are correct
D	Select transistors with high beta

32. - E7C15

What is a crystal lattice filter?

Select	Answer
A	A filter with narrow bandwidth and steep skirts made using quartz crystals
B	An audio filter made with four quartz crystals that resonate at 1kHz intervals
C	A power supply filter made with interlaced quartz crystals
D	A filter with wide bandwidth and shallow skirts made using quartz crystals

33. - E7D08

What type of circuit is shown in Figure E7-3?

Select	Answer
A	Emitter follower
B	Linear voltage regulator
C	Grounded emitter amplifier
D	Switching voltage regulator

34. - E7E03

How does an analog phase modulator function?

Select	Answer
A	By varying the tuning of a microphone preamplifier to produce PM signals
B	By varying the tuning of a microphone preamplifier to produce AM signals
C	By varying the tuning of an amplifier tank circuit to produce PM signals
D	By varying the tuning of an amplifier tank circuit to produce AM signals

35. - E7F03

What type of digital signal processing filter is used to generate an SSB signal?

Select	Answer
A	An adaptive filter
B	A Hilbert-transform filter
C	A notch filter
D	An elliptical filter

36. - E7G03

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

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

37. - E7H14

What is a phase-locked loop circuit?

Select	Answer
A	An electronic circuit also known as a monostable multivibrator
B	An electronic circuit consisting of a precision push-pull amplifier with a differential input
C	An electronic servo loop consisting of a phase detector, a low-pass filter, a voltage-controlled oscillator, and a stable reference oscillator
D	An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator

38. - E8A09

How many levels can an analog-to-digital converter with 8 bit resolution encode?

Select	Answer
A	256 divided by the gain of the input amplifier
B	8 multiplied by the gain of the input amplifier
C	8
D	256

39. - E8B08

What describes Orthogonal Frequency Division Multiplexing?

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

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	Binary Coded Decimal Code
C	Extended Binary Coded Decimal Interchange Code
D	Gray code

41. - E8D03

How does the spread spectrum technique of frequency hopping work?

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

42. - E9A16

What is the effective radiated power relative to a dipole of a repeater station with 200 watts transmitter power output, 4 dB feed line loss, 3.2 dB duplexer loss, 0.8 dB circulator loss, and 10 dBd antenna gain?

Select	Answer
A	126 watts
B	300 watts
C	317 watts
D	2000 watts

43. - E9B14

What type of information can be obtained by submitting the details of a proposed new antenna to a modeling program?

Select	Answer
A	All of these choices are correct
B	Polar plots of the far field elevation and azimuth patterns
C	Antenna gain
D	SWR vs frequency charts

44. - E9C11

How is the far-field elevation pattern of a vertically polarized antenna affected by being mounted over seawater versus rocky ground?

Select	Answer
A	Both the high-angle and low-angle radiation decrease
B	The low-angle radiation decreases
C	The low-angle radiation increases
D	The high-angle radiation increases

45. - E9D08

What happens as the Q of an antenna increases?

Select	Answer
A	SWR bandwidth decreases
B	More common-mode current is present on the feed line
C	Gain is reduced
D	SWR bandwidth increases

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 stub match
B	The omega match
C	The delta match
D	The gamma match

47. - E9F14

What impedance does a 1/2 wavelength transmission line present to a generator when the line is shorted at the far end?

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

48. - E9G03

Which of the following is often determined using a Smith chart?

Select	Answer
A	Impedance and SWR values in transmission lines
B	Trigonometric functions
C	Beam headings and radiation patterns
D	Satellite azimuth and elevation bearings

49. - E9H08

What is the function of a sense antenna?

Select	Answer
A	It allows DF antennas to receive signals at different vertical angles
B	It provides diversity reception that cancels multipath signals
C	It modifies the pattern of a DF antenna array to provide a null in one direction
D	It increases the sensitivity of a DF antenna array

50. - E0A09

Which insulating material commonly used as a thermal conductor for some types of electronic devices is extremely toxic if broken or crushed and the particles are accidentally inhaled?

Select	Answer
A	Uranium Hexafluoride
B	Zinc oxide
C	Beryllium Oxide
D	Mica

Figure E6-2

Figure E7-3