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

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1. - E1A09

What is the first action you should take if your digital message forwarding station inadvertently forwards a communication that violates FCC rules?

Select	Answer
A	Notify the originating station that the communication does not comply with FCC rules
B	Discontinue forwarding the communication as soon as you become aware of it
C	Discontinue forwarding all messages
D	Notify the nearest FCC Field Engineer's office

2. - E1B05

What is the National Radio Quiet Zone?

Select	Answer
A	An area in New Mexico surrounding the White Sands Test Area
B	An area in Puerto Rico surrounding the Arecibo Radio Telescope
C	An area surrounding the National Radio Astronomy Observatory
D	An area in Florida surrounding Cape Canaveral

3. - E1C05

When may an automatically controlled station originate third party communications?

Select	Answer
A	Only when transmitting RTTY or data emissions
B	Never
C	When approved by the National Telecommunication and Information Administration
D	When agreed upon by the sending or receiving station

4. - E1D10

Which amateur stations are eligible to be telecommand stations?

Select	Answer
A	Any amateur station so designated by the space station licensee, subject to the privileges of the class of operator license held by the control operator
B	All of these choices are correct
C	Any amateur station designated by NASA
D	Any amateur station so designated by the ITU

5. - E1E09

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

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

6. - E1F08

Which of the following types of amateur station communications are prohibited?

Select	Answer
A	Communications that have a political content, except as allowed by the Fairness Doctrine
B	Communications in a language other than English
C	Communications that have a religious content
D	Communications transmitted for hire or material compensation, except as otherwise provided in the rules

7. - E2A11

What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?

Select	Answer
A	A linearly polarized antenna
B	A log-periodic dipole array
C	A circularly polarized antenna
D	An isotropic antenna

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. - E2C09

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

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

10. - E2D06

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

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

11. - E2E10

Which of these digital modes has the narrowest bandwidth?

Select	Answer
A	170 Hz shift, 45 baud RTTY
B	PSK31
C	MFSK16
D	300-baud packet

12. - E3A12

What is the cause of auroral activity?

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

13. - E3B13

Why is chordal hop propagation desirable?

Select	Answer
A	Atmospheric noise is lower in the direction of chordal hop propagation
B	The MUF for chordal hop propagation is much lower than for normal skip propagation
C	Signals travel faster along ionospheric chords
D	The signal experiences less loss along the path compared to normal skip propagation

14. - E3C03

Which of the following signal paths is most likely to experience high levels of absorption when the A index or K index is elevated?

Select	Answer
A	Sporadic-E
B	Polar paths
C	Transequatorial propagation
D	NVIS

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

16. - E4B03

If a frequency counter with a specified accuracy of +/- 1.0 ppm reads 146,520,000 Hz, what is the most the actual frequency being measured could differ from the reading?

Select	Answer
A	165.2 Hz
B	1.4652 MHz
C	146.52 Hz
D	14.652 kHz

17. - E4C02

Which of the following portions of a receiver can be effective in eliminating image signal interference?

Select	Answer
A	A narrow IF filter
B	A properly adjusted product detector
C	A notch filter
D	A front-end filter or pre-selector

18. - E4D11

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

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

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

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

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	220 seconds
B	440 seconds
C	110 seconds
D	55 seconds

22. - E5C02

How are impedances described in polar coordinates?

Select	Answer
A	By X and R values
B	By phase angle and amplitude
C	By Y and G values
D	By real and imaginary parts

23. - E5D18

How many watts are consumed in a circuit having a power factor of 0.71 if the apparent power is 500VA?

Select	Answer
A	252 W
B	704 W
C	1.42 mW
D	355 W

24. - E6A09

What is a depletion-mode FET?

Select	Answer
A	An FET that has no current flow between source and drain when no gate voltage is applied
B	Any FET for which holes are the majority carriers
C	An FET that exhibits a current flow between source and drain when no gate voltage is applied
D	Any FET without a channel

25. - E6B07

What is the failure mechanism when a junction diode fails due to excessive current?

Select	Answer
A	Charge carrier depletion
B	Excessive junction temperature
C	Excessive inverse voltage
D	Insufficient forward voltage

26. - E6C02

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

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

27. - E6D14

Which type of slug material decreases inductance when inserted into a coil?

Select	Answer
A	Brass
B	Ceramic
C	Powdered-iron
D	Ferrite

28. - E6E05

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

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

29. - E6F13

What is a liquid crystal display (LCD)?

Select	Answer
A	A display that uses a glowing liquid to remain brightly lit in dim light
B	A display utilizing a crystalline liquid and polarizing filters which becomes opaque when voltage is applied
C	A modern replacement for a quartz crystal oscillator which displays its fundamental frequency
D	A frequency-determining unit for a transmitter or receiver

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 only produces logic "0" at its output when all inputs are logic "1"
C	It produces logic "0" at its output if all inputs are logic "1"
D	It produces logic "1" at its output if any or 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	Transmission of spurious signals
C	All of these choices are correct
D	Creation of parasitic oscillations

32. - E7C15

What is a crystal lattice filter?

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

33. - E7D01

What is one characteristic of a linear electronic voltage regulator?

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

34. - E7E04

What is one way a single-sideband phone signal can be generated?

Select	Answer
A	By using a balanced modulator followed by a filter
B	By using a loop modulator followed by a mixer
C	By using a reactance modulator followed by a mixer
D	By driving a product detector with a DSB signal

35. - E7F12

What digital process is applied to I and Q signals in order to recover the baseband modulation information?

Select	Answer
A	Fast Fourier Transform
B	Quadrature mixing
C	Decimation
D	Signal conditioning

36. - E7G06

Which of the following is the most appropriate use of an op-amp active filter?

Select	Answer
A	As an audio filter in a receiver
B	For smoothing power supply output
C	As a high-pass filter used to block RFI at the input to receivers
D	As a low-pass filter used between a transmitter and a transmission line

37. - E7H03

How is positive feedback supplied in a Hartley oscillator?

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

38. - E8A05

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

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

39. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal is divided into packets of information
B	The transmitted signal jumps from band to band at a predetermined rate
C	Two or more information streams are merged into a baseband, which then modulates the transmitter
D	Two or more information streams are merged into a digital combiner, which then pulse position modulates the transmitter

40. - E8C01

How is Forward Error Correction implemented?

Select	Answer
A	By varying the frequency shift of the transmitted signal according to a predefined algorithm
B	By transmitting extra data that may be used to detect and correct transmission errors
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. - E8D05

What is the most common method of reducing key clicks?

Select	Answer
A	Low-pass filters at the transmitter output
B	Reduce keying waveform rise and fall times
C	Increase keying waveform rise and fall times
D	High-pass filters at the transmitter output

42. - E9A05

What is included in the total resistance of an antenna system?

Select	Answer
A	Transmission-line resistance plus radiation resistance
B	Radiation resistance plus space impedance
C	Radiation resistance plus ohmic resistance
D	Radiation resistance plus transmission resistance

43. - E9B01

In the antenna radiation pattern shown in Figure E9-1, what is the 3 dB beam-width?

Select	Answer
A	75 degrees
B	30 degrees
C	50 degrees
D	25 degrees

44. - E9C15

How does the radiation pattern of a horizontally polarized 3-element beam antenna vary with its height above ground?

Select	Answer
A	The main lobe takeoff angle increases with increasing height
B	The horizontal beam width increases with height
C	The horizontal beam width decreases with height
D	The main lobe takeoff angle decreases with increasing height

45. - E9D06

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

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

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 delta match
C	The omega match
D	The gamma match

47. - E9F10

What impedance does a 1/8 wavelength transmission line present to a generator when the line is shorted at the far end?

Select	Answer
A	An inductive reactance
B	A capacitive reactance
C	The same as the characteristic impedance of the line
D	The same as the input impedance to the final generator stage

48. - E9G08

What is the process of normalization with regard to a Smith chart?

Select	Answer
A	Reassigning resistance values with regard to the reactance axis
B	Reassigning prime center with regard to the reactance axis
C	Reassigning reactance values with regard to the resistance axis
D	Reassigning impedance values with regard to the prime center

49. - E9H07

Why is it advisable to use an RF attenuator on a receiver being used for direction finding?

Select	Answer
A	It compensates for the effects of an isotropic antenna, thereby improving directivity
B	It prevents receiver overload which could make it difficult to determine peaks or nulls
C	It narrows the bandwidth of the received signal to improve signal to noise ratio
D	It reduces loss of received signals caused by antenna pattern nulls, thereby increasing sensitivity

50. - E0A04

When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?

Select	Answer
A	Only commercial transmitters
B	Only the most powerful transmitter
C	Each transmitter operating with a duty-cycle greater than 50 percent
D	Each transmitter that produces 5 percent or more of its MPE limit at accessible locations

Figure E9-1