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

2. - E1B09

Which amateur stations may be operated under RACES rules?

Select	Answer
A	Only those club stations licensed to Amateur Extra class operators
B	Any FCC-licensed amateur station certified by the responsible civil defense organization for the area served
C	Any FCC-licensed amateur station except a Technician class
D	Any FCC-licensed amateur station participating in the Military Auxiliary Radio System (MARS)

3. - E1C09

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

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

4. - E1D11

Which amateur stations are eligible to operate as Earth stations?

Select	Answer
A	Any amateur station whose licensee has filed a pre-space notification with the FCC's International Bureau
B	Only those of Amateur Extra Class operators
C	Only those of General, Advanced or Amateur Extra Class operators
D	Any amateur station, subject to the privileges of the class of operator license held by the control operator

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	5
D	4

6. - E1F02

What privileges are authorized in the U.S. to persons holding an amateur service license granted by the Government of Canada?

Select	Answer
A	Full privileges, up to and including those of the Extra Class License, on the 80, 40, 20, 15, and 10 meter bands
B	The operating terms and conditions of the Canadian amateur service license, not to exceed U.S. Extra Class privileges
C	All privileges of the Extra Class license
D	None, they must obtain a U.S. license

7. - E2A10

Why may the received signal from an amateur satellite exhibit a rapidly repeating fading effect?

Select	Answer
A	Because of ionospheric absorption
B	Because of the satellite's low orbital altitude
C	Because of the Doppler Effect
D	Because the satellite is spinning

8. - E2B19

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

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

9. - E2C05

What is the function of a DX QSL Manager?

Select	Answer
A	To relay calls to and from a DX station
B	To handle the receiving and sending of confirmation cards for a DX station
C	To run a net to allow many stations to contact a rare DX station
D	To allocate frequencies for DXpeditions

10. - E2D09

Which of these digital modes has the fastest data throughput under clear communication conditions?

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

11. - E2E02

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

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

12. - E3A16

Which of the following best describes electromagnetic waves traveling in free space?

Select	Answer
A	Electric and magnetic fields become aligned as they travel
B	Changing electric and magnetic fields propagate the energy
C	The waves are reflected by the ionosphere and return to their source
D	The energy propagates through a medium with a high refractive index

13. - E3B14

What happens to linearly polarized radio waves that split into ordinary and extraordinary waves in the ionosphere?

Select	Answer
A	They are bent toward the magnetic poles
B	Their polarization is randomly modified
C	They become elliptically polarized
D	They become phase-locked

14. - E3C15

What might a sudden rise in radio background noise indicate?

Select	Answer
A	Increased transequatorial propagation likely
B	Long-path propagation is occurring
C	A solar flare has occurred
D	A meteor ping

15. - E4A04

What determines the upper frequency limit for a computer soundcard-based oscilloscope program?

Select	Answer
A	Q of the interface of the interface circuit
B	All of these choices are correct
C	Amount of memory on the soundcard
D	Analog-to-digital conversion speed of the soundcard

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	14.652 kHz
D	146.52 Hz

17. - E4C10

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

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

18. - E4D06

What is the term for unwanted signals generated by the mixing of two or more signals?

Select	Answer
A	Amplifier desensitization
B	Neutralization
C	Adjacent channel interference
D	Intermodulation interference

19. - E4E12

What is one disadvantage of using some types of automatic DSP notch-filters when attempting to copy CW signals?

Select	Answer
A	Received CW signals will appear to be modulated at the DSP clock frequency
B	Any nearby signal passing through the DSP system will overwhelm the desired signal
C	A DSP filter can remove the desired signal at the same time as it removes interfering signals
D	Ringing in the DSP filter will completely remove the spaces between the CW characters

20. - E5A09

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

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

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

22. - E5C08

What coordinate system is often used to display the phase angle of a circuit containing resistance, inductive and/or capacitive reactance?

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

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	1.42 mW
B	355 W
C	704 W
D	252 W

24. - E6A02

Which of the following semiconductor materials contains excess free electrons?

Select	Answer
A	Insulated gate
B	N-type
C	Bipolar
D	P-type

25. - E6B12

What is one common use for PIN diodes?

Select	Answer
A	As a constant voltage source
B	As a high voltage rectifier
C	As an RF switch
D	As a constant current source

26. - E6C05

What is an advantage of CMOS logic devices over TTL devices?

Select	Answer
A	Immune to damage from static discharge
B	Lower distortion
C	Differential output capability
D	Lower power consumption

27. - E6D10

What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?

Select	Answer
A	Toroidal cores make it easier to couple the magnetic energy into other components
B	Toroidal cores confine most of the magnetic field within the core material
C	Toroidal cores have lower Q characteristics
D	Toroidal cores exhibit greater hysteresis

28. - E6E04

Which is the most common input and output impedance of circuits that use MMICs?

Select	Answer
A	50 ohms
B	450 ohms
C	10 ohms
D	300 ohms

29. - E6F06

Which of these materials is affected the most by photoconductivity?

Select	Answer
A	An ordinary metal
B	A liquid semiconductor
C	A crystalline semiconductor
D	A heavy metal

30. - E7A06

What is a characteristic of a monostable multivibrator?

Select	Answer
A	It switches momentarily to the opposite binary state and then returns to its original state after a set time
B	It produces a continuous square wave oscillating between 1 and 0
C	It maintains a constant output voltage, regardless of variations in the input voltage
D	It stores one bit of data in either a 0 or 1 state

31. - E7B06

Which of the following amplifier types reduces or eliminates even order harmonics?

Select	Answer
A	Class AB
B	Push-push
C	Push-pull
D	Class C

32. - E7C12

Which describes a Pi-L-network used for matching a vacuum tube final amplifier to a 50 ohm unbalanced output?

Select	Answer
A	A matching network in which all components are isolated from ground
B	A network with only three discrete parts
C	A Phase Inverter Load network
D	A Pi-network with an additional series inductor on the output

33. - E7D16

When several electrolytic filter capacitors are connected in series to increase the operating voltage of a power supply filter circuit, why should resistors be connected across each capacitor?

Select	Answer
A	To provide a minimum load current to reduce voltage excursions at light loads
B	To provide a safety bleeder to discharge the capacitors when the supply is off
C	To equalize, as much as possible, the voltage drop across each capacitor
D	All of these choices are correct

34. - E7E02

What is the function of a reactance modulator?

Select	Answer
A	To produce PM signals by using an electrically variable inductance or capacitance
B	To produce AM signals by using an electrically variable resistance
C	To produce PM signals by using an electrically variable resistance
D	To produce AM signals by using an electrically variable inductance or capacitance

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	Missing codes and jitter
C	Data storage transfer rate
D	Sample clock phase noise

36. - E7G10

What absolute voltage gain can be expected from the circuit in Figure E7-4 when R1 is 1800 ohms and RF is 68 kilohms?

Select	Answer
A	1
B	38
C	76
D	0.03

37. - E7H13

Which of the following is a technique for providing highly accurate and stable oscillators needed for microwave transmission and reception?

Select	Answer
A	Use a temperature-controlled high Q dielectric resonator
B	All of these choices are correct
C	Use a rubidium stabilized reference oscillator
D	Use a GPS signal reference

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. - E8B10

What describes frequency division multiplexing?

Select	Answer
A	The transmitted signal jumps from band to band at a predetermined rate
B	The transmitted signal is divided into packets of information
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 the receiving station repeating each block of three data characters
B	By transmitting a special algorithm to the receiving station along with the data characters
C	By transmitting extra data that may be used to detect and correct transmission errors
D	By varying the frequency shift of the transmitted signal according to a predefined algorithm

41. - E8D08

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

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

42. - E9A03

Why would one need to know the feed point impedance of an antenna?

Select	Answer
A	To measure the near-field radiation density from a transmitting antenna
B	To match impedances in order to minimize standing wave ratio on the transmission line
C	To calculate the front-to-side ratio of the antenna
D	To calculate the front-to-back ratio of the antenna

43. - E9B13

What does the abbreviation NEC stand for when applied to antenna modeling programs?

Select	Answer
A	Numeric Electrical Computation
B	National Electrical Code
C	Numerical Electromagnetic Code
D	Next Element Comparison

44. - E9C14

How does the performance of a horizontally polarized antenna mounted on the side of a hill compare with the same antenna mounted on flat ground?

Select	Answer
A	The horizontal beam width decreases in the downhill direction
B	The main lobe takeoff angle decreases in the downhill direction
C	The horizontal beam width increases in the uphill direction
D	The main lobe takeoff angle increases in the downhill direction

45. - E9D03

Where should a high Q loading coil be placed to minimize losses in a shortened vertical antenna?

Select	Answer
A	Near the center of the vertical radiator
B	As low as possible on the vertical radiator
C	At a voltage node
D	As close to the transmitter as possible

46. - E9E01

What system matches a higher impedance transmission line to a lower impedance antenna by connecting the line to the driven element in two places spaced a fraction of a wavelength each side of element center?

Select	Answer
A	The stub matching system
B	The omega matching system
C	The delta matching system
D	The gamma matching system

47. - E9F12

What impedance does a 1/4 wavelength transmission line present to a generator when the line is open at the far end?

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

48. - E9G08

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

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

49. - E9H08

What is the function of a sense antenna?

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

50. - E0A06

Why are there separate electric (E) and magnetic (H) field MPE limits?

Select	Answer
A	Ground reflections and scattering make the field impedance vary with location
B	All of these choices are correct
C	E field and H field radiation intensity peaks can occur at different locations
D	The body reacts to electromagnetic radiation from both the E and H fields

Figure E7-4