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

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1. - E1A07

Which amateur band requires transmission on specific channels rather than on a range of frequencies?

Select	Answer
A	60 meter band
B	30 meter band
C	17 meter band
D	12 meter band

2. - E1B11

What is the permitted mean power of any spurious emission relative to the mean power of the fundamental emission from a station transmitter or external RF amplifier installed after January 1, 2003 and transmitting on a frequency below 30 MHZ?

Select	Answer
A	At least 53 dB below
B	At least 43 dB below
C	At least 63 dB below
D	At least 73 dB below

3. - E1C10

What types of amateur stations may automatically retransmit the radio signals of other amateur stations?

Select	Answer
A	Only auxiliary, repeater or space stations
B	Only auxiliary, beacon or space stations
C	Only earth stations, repeater stations or model craft
D	Only beacon, repeater or space stations

4. - E1D01

What is the definition of the term telemetry?

Select	Answer
A	Two-way radiotelephone transmissions in excess of 1000 feet
B	One-way transmission of measurements at a distance from the measuring instrument
C	One-way transmission that initiates, modifies, or terminates the functions of a device at a distance
D	Two-way single channel transmissions of data

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. - E1F10

What is the maximum permitted transmitter peak envelope power for an amateur station transmitting spread spectrum communications?

Select	Answer
A	1.5 kW
B	1 W
C	10 W
D	1.5 W

7. - E2A03

What is the orbital period of an Earth satellite?

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

8. - E2B19

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

Select	Answer
A	They are not permitted above 54 MHz
B	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
C	None; they are allowed on all amateur frequencies
D	They are restricted to 7.245 MHz, 14.245 MHz, 21.345 MHz, and 28.945 MHz

9. - E2C04

What type of transmission is most often used for a ham radio mesh network?

Select	Answer
A	Frequency division multiplex in the 24 GHz band
B	Store and forward on the 440 MHz band
C	Spread spectrum in the 2.4 GHz band
D	Multiple Frequency Shift Keying in the 10 GHz band

10. - E2D05

Which of the following techniques is normally used by low Earth orbiting digital satellites to relay messages around the world?

Select	Answer
A	Node hopping
B	Digipeating
C	Store-and-forward
D	Multi-satellite relaying

11. - E2E01

Which type of modulation is common for data emissions below 30 MHz?

Select	Answer
A	DTMF tones modulating an FM signal
B	FSK
C	Spread spectrum
D	Pulse modulation

12. - E3A05

Tropospheric propagation of microwave signals often occurs along what weather related structure?

Select	Answer
A	Lightning discharges
B	Sprites and jets
C	Warm and cold fronts
D	Gray-line

13. - E3B05

Which amateur bands typically support long-path propagation?

Select	Answer
A	160 meters to 10 meters
B	30 meters to 10 meters
C	160 meters to 40 meters
D	6 meters to 2 meters

14. - E3C09

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

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

15. - E4A13

How is the compensation of an oscilloscope probe typically adjusted?

Select	Answer
A	A square wave is displayed and the probe is adjusted until the horizontal portions of the displayed wave are as nearly flat as possible
B	A high frequency sine wave is displayed and the probe is adjusted for maximum amplitude
C	A DC voltage standard is displayed and the probe is adjusted until the displayed voltage is accurate
D	A frequency standard is displayed and the probe is adjusted until the deflection time is accurate

16. - E4B14

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

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

17. - E4C14

What transmit frequency might generate an image response signal in a receiver tuned to 14.300 MHz and which uses a 455 kHz IF frequency?

Select	Answer
A	14.445 MHz
B	14.755 MHz
C	13.845 MHz
D	15.210 MHz

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

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	Common mode currents on the shield and conductors
D	Low inductance ground connections at both ends of the shield

20. - E5A13

What is an effect of increasing Q in a resonant circuit?

Select	Answer
A	Fewer components are needed for the same performance
B	Internal voltages and circulating currents increase
C	Parasitic effects are minimized
D	Phase shift can become uncontrolled

21. - E5B06

What is susceptance?

Select	Answer
A	A measure of the efficiency of a transformer
B	The inverse of reactance
C	The magnetic impedance of a circuit
D	The ratio of magnetic field to electric field

22. - E5C17

Which point on Figure E5-2 best represents the impedance of a series circuit consisting of a 300 ohm resistor, a 0.64-microhenry inductor and an 85-picofarad capacitor at 24.900 MHz?

Select	Answer
A	Point 1
B	Point 5
C	Point 8
D	Point 3

23. - E5D02

Why is it important to keep lead lengths short for components used in circuits for VHF and above?

Select	Answer
A	All of these choices are correct
B	To maintain component lifetime
C	To avoid unwanted inductive reactance
D	To increase the thermal time constant

24. - E6A04

What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?

Select	Answer
A	Donor impurity
B	Insulator impurity
C	Acceptor impurity
D	N-type impurity

25. - E6B10

In Figure E6-3, what is the schematic symbol for a light-emitting diode?

Select	Answer
A	5
B	6
C	1
D	7

26. - E6C02

What happens when the level of a comparator's input signal crosses the threshold?

Select	Answer
A	The comparator enters latch-up
B	The comparator changes its output state
C	The IC input can be damaged
D	The feedback loop becomes unstable

27. - E6D12

What is the definition of saturation in a ferrite core inductor?

Select	Answer
A	Adjacent inductors become over-coupled
B	The inductor windings are over coupled
C	The ability of the inductor's core to store magnetic energy has been exceeded
D	The inductor's voltage rating is exceeded causing a flashover

28. - E6E05

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

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

29. - E6F04

What is the photovoltaic effect?

Select	Answer
A	The conversion of voltage to current when exposed to light
B	The conversion of light to electrical energy
C	The tendency of a battery to discharge when used outside
D	The conversion of electrical energy to mechanical energy

30. - E7A08

What logical operation does an OR gate perform?

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

31. - E7B16

What is the effect of intermodulation products in a linear power amplifier?

Select	Answer
A	Low efficiency
B	All of these choices are correct
C	Transmission of spurious signals
D	Creation of parasitic oscillations

32. - E7C02

Which of the following is a property of a T-network with series capacitors and a parallel shunt inductor?

Select	Answer
A	It is a band-pass filter
B	It is a notch filter
C	It is a high-pass filter
D	It is a low-pass filter

33. - E7D03

What device is typically used as a stable reference voltage in a linear voltage regulator?

Select	Answer
A	A varactor diode
B	An SCR
C	A Zener diode
D	A tunnel diode

34. - E7E10

How does a diode detector function?

Select	Answer
A	By breakdown of the Zener voltage
B	By mixing signals with noise in the transition region of the diode
C	By sensing the change of reactance in the diode with respect to frequency
D	By rectification and filtering of RF signals

35. - E7F07

What function can a Fast Fourier Transform perform?

Select	Answer
A	Converting digital signals to analog form
B	Converting digital signals from the time domain to the frequency domain
C	Converting 8-bit data to 16 bit data
D	Converting analog signals to digital form

36. - E7G08

How does the gain of an ideal operational amplifier vary with frequency?

Select	Answer
A	It decreases linearly with increasing frequency
B	It decreases logarithmically with increasing frequency
C	It does not vary with frequency
D	It increases linearly with increasing frequency

37. - E7H04

How is positive feedback supplied in a Colpitts oscillator?

Select	Answer
A	Through a neutralizing capacitor
B	Through a capacitive divider
C	Through link coupling
D	Through a tapped coil

38. - E8A05

What would be the most accurate way of measuring the RMS voltage of a complex waveform?

Select	Answer
A	By using an absorption wave meter
B	By measuring the voltage with a D'Arsonval meter
C	By measuring the heating effect in a known resistor
D	By using a grid dip meter

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	1000
B	3
C	0.3
D	3000

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By transmitting extra data that may be used to detect and correct transmission errors
B	By varying the frequency shift of the transmitted signal according to a predefined algorithm
C	By the receiving station repeating each block of three data characters
D	By transmitting a special algorithm to the receiving station along with the data characters

41. - E8D09

What is considered a good minimum IMD level for an idling PSK signal?

Select	Answer
A	+10 dB
B	-30 dB
C	-20 dB
D	+15 dB

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	2000 watts
B	126 watts
C	300 watts
D	317 watts

43. - E9B05

What type of antenna pattern over real ground is shown in Figure E9-2?

Select	Answer
A	Azimuth
B	Elevation
C	Radiation resistance
D	Polarization

44. - E9C06

What is the effect of a terminating resistor on a rhombic antenna?

Select	Answer
A	It changes the radiation pattern from bidirectional to unidirectional
B	It reflects the standing waves on the antenna elements back to the transmitter
C	It changes the radiation pattern from horizontal to vertical polarization
D	It decreases the ground loss

45. - E9D11

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

Select	Answer
A	A wide flat copper strap
B	A single 12 gauge or 10 gauge stainless steel wire
C	A cable with six or seven 18 gauge conductors in parallel
D	A resistive wire, such as spark plug wire

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 gamma match
C	The delta match
D	The omega 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	The same as the generator output impedance
B	Very low impedance
C	Very high impedance
D	The same as the characteristic impedance of the transmission line

48. - E9G01

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

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

49. - E9H02

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

Select	Answer
A	Low loss coax transmission line is essential for good performance
B	All of these choices are correct
C	Atmospheric noise is so high that gain over a dipole is not important
D	They must be erected at least 1/2 wavelength above the ground to attain good directivity

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	Zinc oxide
B	Beryllium Oxide
C	Uranium Hexafluoride
D	Mica

Figure E5-2

Figure E6-3

Figure E9-2