Amateur Radio General Exam Q+Right Answer G8B To G0B

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Amateur Radio General

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G8B01 (A)
What receiver stage combines a 14.250 MHz input signal with a 13.795 MHz oscillator signal to produce a 455 kHz intermediate frequency (IF) signal?
A. Mixer
G8B02 (B)
If a receiver mixes a 13.800 MHz VFO with a 14.255 MHz received signal to produce
a 455 kHz intermediate frequency (IF) signal, what type of interference will a 13.345 MHz signal produce in the receiver?

B. Image response
G8B03 (A)
What stage in a transmitter would change a 5.3 MHz input signal to 14.3 MHz?
A. A mixer
G8B04 (D)
What is the name of the stage in a VHF FM transmitter that selects a harmonic of an HF signal to reach the desired operating frequency?

D. Multiplier
G8B05 (C)
Why isn't frequency modulated (FM) phone used below 29.5 MHz?

C. The bandwidth would exceed FCC limits
G8B06 (D)
What is the total bandwidth of an FM-phone transmission having a 5 kHz deviation and a 3 kHz modulating frequency?

D. 16 kHz
G8B07 (B)
What is the frequency deviation for a 12.21-MHz reactance-modulated oscillator in a 5-kHz deviation, 146.52-MHz FM-phone transmitter?

B. 416.7 Hz
G8B08 (C)
How is frequency shift related to keying speed in an FSK signal?

C. Greater keying speeds require greater frequency shifts
G8B09 (B)
What do RTTY, Morse code, PSK31 and packet communications have in common?

B. They are digital modes
G8B10 (B)
When transmitting a data mode signal, why is it important to know the duty cycle of the mode you are using?

B. To prevent damage to your transmitter's final output stage
G8B11 (D)
What part of the 20 meter band is most commonly used for PSK31 operation?

D. Below the RTTY segment, near 14.070 MHz
G8B12 (A)
What is another term for the mixing of two RF signals?
A. Heterodyning
G9A01 (A)
Which of the following factors help determine the characteristic impedance of a parallel conductor antenna feedline?
A. The distance between the centers of the conductors and the radius of the conductors
G9A02 (B)
What is the typical characteristic impedance of coaxial cables used for antenna feedlines at amateur stations?

B. 50 and 75 ohms
G9A03 (D)
What is the characteristic impedance of flat ribbon TV type twin lead?

D. 300 ohms
G9A04 (C)
What is a common reason for the occurrence of reflected power at the point where a feedline connects to an antenna?

C. A difference between feedline impedance and antenna feed point impedance
G9A05 (D)
What must be done to prevent standing waves on an antenna feedline?

D. The antenna feed point impedance must be matched to the characteristic impedance of the feedline
G9A06 (C)
Which of the following is a reason for using an inductively coupled matching network between the transmitter and parallel conductor feed line feeding an antenna?

C. To match the unbalanced transmitter output to the balanced parallel conductor feedline
G9A07 (B)
How does the attenuation of coaxial cable change as the frequency of the signal it is carrying increases?

B. It increases
G9A08 (D)
In what values are RF feed line losses usually expressed?
D. dB per 100 ft
G9A09 (A)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a non-reactive load having a 200-ohm impedance?
A. 4:1
G9A10 (D)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a non-reactive load having a 10-ohm impedance?

D. 5:1
G9A11 (B)
What standing-wave-ratio will result from the connection of a 50-ohm feed line to a
non-reactive load having a 50-ohm impedance?

B. 1:1
G9A12 (A)
What would be the SWR if you feed a vertical antenna that has a 25-ohm feed-point impedance with 50-ohm coaxial cable?
A. 2:1
G9A13 (C)
What would be the SWR if you feed a folded dipole antenna that has a 300-ohm feed-point impedance with 50-ohm coaxial cable?

C. 6:1
G9A14 (B) 
If the SWR on an antenna feedline is 5 to 1, and a matching network at the transmitter end of the feedline is adjusted to 1 to 1 SWR, what is the resulting SWR on the feedline?

B. 5 to 1
G9B01 (B)
What is one disadvantage of a directly fed random-wire antenna?

B. You may experience RF burns when touching metal objects in your station
G9B02 (D)
What is an advantage of downward sloping radials on a ground-plane antenna?
D. They can be adjusted to bring the feed-point impedance closer to 50 ohms
G9B03 (B)
What happens to the feed-point impedance of a ground-plane antenna when its radials are changed from horizontal to downward-sloping?

B. It increases
G9B04 (A)
What is the low angle azimuthal radiation pattern of an ideal half-wavelength dipole antenna installed 1/2 wavelength high and parallel to the earth?
A. It is a figure-eight at right angles to the antenna
G9B05 (C)
How does antenna height affect the horizontal (azimuthal) radiation pattern of a horizontal dipole HF antenna?
C. If the antenna is less than 1/2 wavelength high, the azimuthal pattern is almost omnidirectional
G9B06 (C)
Where should the radial wires of a ground-mounted vertical antenna system be placed?

C. On the surface or buried a few inches below the ground
G9B07 (B)
How does the feed-point impedance of a 1/2 wave dipole antenna change as the antenna is lowered from 1/4 wave above ground?

B. It steadily decreases
G9B08 (A) 
How does the feed-point impedance of a 1/2 wave dipole change as the feed-point location is moved from the center toward the ends?
A. It steadily increases
G9B09 (A)
Which of the following is an advantage of a horizontally polarized as compared to vertically polarized HF antenna?
A. Lower ground reflection losses
G9B10 (D) 
What is the approximate length for a 1/2-wave dipole antenna cut for 14.250 MHz?

D. 32.8 feet
G9B11 (C)
What is the approximate length for a 1/2-wave dipole antenna cut for 3.550 MHz?

C. 131.8 feet
G9B12 (A)
What is the approximate length for a 1/4-wave vertical antenna cut for 28.5 MHz?
A. 8.2 feet
G9C01 (A)
How can the SWR bandwidth of a Yagi antenna be increased?
A. Use larger diameter elements
G9C02 (B)
What is the approximate length of the driven element of a Yagi antenna?

B. 1/2 wavelength
G9C03 (B)
Which statement about a three-element single-band Yagi antenna is true?

B. The director is normally the shortest parasitic element
G9C04 (A)
Which statement about a Yagi antenna is true?
A. The reflector is normally the longest parasitic element
G9C05 (A)
What is one effect of increasing the boom length and adding directors to a Yagi antenna?
A. Gain increases
G9C06 (C)
Which of the following is a reason why a Yagi antenna is often used for radio communications on the 20 meter band?

C. It helps reduce interference from other stations to the side or behind the antenna
G9C07 (C)
What does "front-to-back ratio" mean in reference to a Yagi antenna?

C. The power radiated in the major radiation lobe compared to the power radiated in exactly the opposite direction
G9C08 (D)
What is meant by the "main lobe" of a directive antenna?

D. The direction of maximum radiated field strength from the antenna
G9C09 (A)
What is the approximate maximum theoretical forward gain of a 3 Element Yagi antenna?
A. 9.7 dBi
G9C10 (D)
Which of the following is a Yagi antenna design variable that could be adjusted to optimize forward gain, front-to-back ratio, or SWR bandwidth?
A. The physical length of the boom
B. The number of elements on the boom
C. The spacing of each element along the boom
D. All of these choices are correct
G9C11 (A)
What is the purpose of a "gamma match" used with Yagi antennas?
A. To match the relatively low feed-point impedance to 50 ohms
G9C12 (D)
Which of the following describes a common method for insulating the driven element of
a Yagi antenna from the metal boom when using a gamma match?

D. None of these answers are correct. No insulation is needed
G9C13 (A)
Approximately how long is each side of a cubical-quad antenna driven element?
A. 1/4 wavelength
G9C14 (B)
How does the forward gain of a 2-element cubical-quad antenna compare to the forward gain of a 3 element Yagi antenna?

B. About the same
G9C15 (B)
Approximately how long is each side of a cubical-quad antenna reflector element?

B. Slightly more than 1/4 wavelength
G9C16 (D)
How does the gain of a two element delta-loop beam compare to the gain of a two element cubical quad antenna?

D. About the same
G9C17 (B)
Approximately how long is each leg of a symmetrical delta-loop antenna Driven element?
B. 1/3 wavelengths
G9C18 (D)
Which of the following antenna types consists of a driven element and some combination of parasitically excited reflector and/or director elements?

D. A Yagi antenna
G9C19 (C)
What type of directional antenna is typically constructed from 2 square loops of wire
each having a circumference of approximately one wavelength at the operating frequency and separated by approximately 0.2 wavelength?

C. A cubical quad antenna
G9C20 (A) 
What happens when the feed-point of a cubical quad antenna is changed from the center
of the lowest horizontal wire to the center of one of the vertical wires?
A. The polarization of the radiated signal changes from horizontal to vertical
G9C21 (D)  
What configuration of the loops of a cubical-quad antenna must be used for the antenna to operate as a beam antenna, assuming one of the elements is used as a reflector?

D. The reflector element must be approximately 5% longer than the driven element
G9D01 (D)
What does the term "NVIS" mean as related to antennas?

D. Near Vertical Incidence Skywave
G9D02 (B)
Which of the following is an advantage of an NVIS antenna?

B. High vertical angle radiation for short skip during the day
G9D03 (D)
At what height above ground is an NVIS antenna typically installed?

D. Between 1/10 and 1/4 wavelength
G9D04 (B) 
How does the gain of two 3-element horizontally polarized Yagi antennas spaced vertically 1/2 wave apart from each other typically compare to the gain of a single 3-element Yagi?

B. Approximately 3 dB higher
G9D05 (D)
What is the advantage of vertical stacking of horizontally polarized Yagi antennas?

D. Narrows the main lobe in elevation
G9D06 (A)
Which of the following is an advantage of a log periodic antenna?
A. Wide bandwidth
G9D07 (A)
Which of the following describes a log periodic antenna?
A. Length and spacing of the elements increases logarithmically from one end of the boom to the other
G9D08 (B)
Why is a Beverage antenna generally not used for transmitting?

B. It has high losses compared to other types of antennas
G9D09 (B)
Which of the following is an application for a Beverage antenna?

B. Directional receiving for low HF bands
G9D10 (D)
Which of the following describes a Beverage antenna?

D. A very long and low receiving antenna that is highly directional
G9D11 (D) 
Which of the following is a disadvantage of multiband antennas?
D. They have poor harmonic rejection
G9D12 (A)
What is the primary purpose of traps installed in antennas?
A. To permit multiband operation
G0A01 (A)
What is one way that RF energy can affect human body tissue?
A. It heats body tissue
G0A02 (B)
Which property is NOT important in estimating if an RF signal exceeds the maximum permissible exposure (MPE)?

B. Its critical angle
G0A03 (B)
Which of the following has the most direct effect on the permitted exposure level of RF radiation?

B. The power level and frequency of the energy
G0A04 (D)
What does "time averaging" mean in reference to RF radiation exposure?
D. The total RF exposure averaged over a certain time
G0A05 (A)
What must you do if an evaluation of your station shows RF energy radiated from your station exceeds permissible limits?
A. Take action to prevent human exposure to the excessive RF fields
G0A06 (C)
Which transmitter(s) at a multiple user site is/are responsible for RF safety compliance?
C. Any transmitter that contributes 5% or more of the MPE
G0A07 (A)
What effect does transmitter duty cycle have when evaluating RF exposure?
A. A lower transmitter duty cycle permits greater short-term exposure levels
G0A08 (C)
Which of the following steps must an amateur operator take to ensure compliance with RF safety regulations?
C. Perform a routine RF exposure evaluation
G0A09 (B)
What type of instrument can be used to accurately measure an RF field?

B. A calibrated field-strength meter with a calibrated antenna
G0A10 (D)
What do the RF safety rules require when the maximum power output capability of an otherwise compliant station is reduced?

D. No further action is required
G0A11 (C)
What precaution should you take if you install an indoor transmitting antenna?

C. Make sure that MPE limits are not exceeded in occupied areas
G0A12 (B)
What precaution should you take whenever you make adjustments or repairs to an antenna?

B. Turn off the transmitter and disconnect the feedline
G0A13 (D)
What precaution should be taken when installing a ground-mounted antenna?

D. It should be installed so no one can be exposed to RF radiation in excess of maximum permissible limits
G0A14 (D)
What is one thing that can be done if evaluation shows that a neighbor might receive more than the allowable limit of RF exposure from the main lobe of a directional antenna?

D. Take precautions to ensure that the antenna cannot be pointed at their house
G0A15 (D) [97.13(c)(1)]
How can you determine that your station complies with FCC RF exposure regulations?
A. By calculation based on FCC OET Bulletin 65
B. By calculation based on computer modeling
C. By measurement of field strength using calibrated equipment
D. All of these choices are correct
G0B01 (A)
Which wire(s) in a four-conductor line cord should be attached to fuses or circuit breakers in a device operated from a 240-VAC single-phase source?
A. Only the "hot" (black and red) wires
G0B02 (C)
What is the minimum wire size that may be safely used for a circuit that draws up to 20 amperes of continuous current?

C. AWG number 12
G0B03 (D)
Which size of fuse or circuit breaker would be appropriate to use with a circuit that uses AWG number 14 wiring?

D. 15 amperes
G0B04 (A)
What is the mechanism by which electrical shock can be lethal?
A. Current through the heart can cause the heart to stop pumping
G0B05 (B)
Which of the following conditions will cause a Ground Fault Circuit Interrupter (GFCI) to disconnect the 120 or 240 Volt AC line power to a device?

B. Current flowing from the hot wire to ground
G0B06 (D)
Why must the metal chassis of every item of station equipment be grounded (assuming
the item has such a chassis)?

D. It ensures that hazardous voltages cannot appear on the chassis
G0B07 (B)
Which of the following should be observed for safety when climbing on a tower using a safety belt or harness?

B. Always attach the belt safety hook to the belt "D" ring with the hook opening away from the tower
G0B08 (B)
What should be done by any person preparing to climb a tower that supports electrically powered devices?

B. Make sure all circuits that supply power to the tower are locked out and tagged
G0B09 (D)
Why is it not safe to use soldered joints with the wires that connect the base of a tower to a system of ground rods?

D. A soldered joint will likely be destroyed by the heat of a lightning strike
G0B10 (A)
Which of the following is a danger from lead-tin solder?
A. Lead can contaminate food if hands are not washed carefully after handling
G0B11 (D)
Which of the following is good engineering practice for lightning protection grounds?

D. They must be bonded together with all other grounds
G0B12 (C) 
What is the purpose of a transmitter power supply interlock?

C. To ensure that dangerous voltages are removed if the cabinet is opened
G0B13 (B)
Which of the following is the most hazardous type of electrical energy?

B. 60 cycle Alternating current
G0B14 (B)
What is the maximum amount of electrical current flow through the human body that can be tolerated safely?
B. 50 microamperes