2007 General Class Questions Pool

This pool is valid for Element 3 exams given on or after July 1, 2007]

SUBELEMENT G4 - AMATEUR RADIO PRACTICES
[5 Exam Questions -- 5 Groups]

G4A - Two-tone Test; amplifier tuning and neutralization; DSP

G4A01
Which of the following is one use for a DSP in an amateur station?
A. To provide adequate grounding?
B. To remove noise from received signals

C. To increase antenna gain
D. To increase antenna bandwidth

G4A02
Which of the following instruments may be used to measure the output of a single-sideband transmitter when performing a two-tone test of amplitude linearity?
A. An audio distortion analyzer ?
B. An oscilloscope

C. A directional wattmeter
D. A high impedance audio voltmeter

G4A03 (D)
Which of the following is needed for a DSP IF filter?
A. An Analog to Digital Converter
B. Digital to Analog Converter
C. A Digital Processor Chip?
D. All of the these answers are correct

G4A04
Which of the following is an advantage of a receiver IF filter created with a DSP as compared to an analog filter??
A. A wide range of filter bandwidths and shapes can be created

B. Fewer digital components are required
C. Mixing products are greatly reduced
D. The DSP filter is much more effective at VHF frequencies

G4A05
How is DSP filtering accomplished?
A. By using direct signal phasing?
B. By converting the signal from analog to digital and using digital processing

C. By up-converting the signal to VHF
D. By converting the signal from digital to analog and taking the difference of mixing products

G4A06
What reading on the plate current meter of a vacuum tube RF power amplifier indicates correct adjustment of the plate tuning control?
A. A pronounced peak ?
B. A pronounced dip

C. No change will be observed
D. A slow, rhythmic oscillation

G4A07
What is the correct adjustment for the "Load" or "Coupling" control of a vacuum tube RF power amplifier?
A. Minimum SWR on the antenna
B. Minimum plate current without exceeding maximum allowable grid current
C. Highest plate voltage while minimizing grid current ?
D. Maximum power output without exceeding maximum allowable plate current

G4A08 (C)
Which of the following techniques is used to neutralize an RF amplifier?
A. Feed-forward compensation
B. Feed-forward cancellation ?
C. Negative feedback
D. Positive feedback

G4A09
What does a neutralizing circuit do in an RF amplifier?
A. It controls differential gain ?
B. It cancels the effects of positive feedback

C. It eliminates AC hum from the power supply
D. It reduces incidental grid modulation

G4A10
What is the reason for neutralizing the final amplifier stage of a transmitter?
A. To limit the modulation index ?
B. To eliminate self oscillations

C. To cut off the final amplifier during standby periods
D. To keep the carrier on frequency

G4A11
What type of transmitter performance does a two-tone test analyze? ?
A. Linearity

B. Carrier and undesired sideband suppression
C. Percentage of frequency modulation
D. Percentage of carrier phase shift

G4A12
What type of signals are used to conduct a two-tone test?
A. Two audio signals of the same frequency shifted 90-degrees ?
B. Two non-harmonically related audio signals

C. Two swept frequency tones
D. Two audio frequency range square wave signals of equal amplitude

G4A13
Which of the following performs automatic notching of interfering carriers?
A. Band pass tuning?
B. A DSP filter

C. Balanced mixing
D. A noise limiter

G4B - Test and monitoring equipment

G4B01
What item of test equipment contains horizontal and vertical channel amplifiers?
A. An ohmmeter
B. A signal generator
C. An ammeter ?
D. An oscilloscope

G4B02
Which of the following is an advantage of an oscilloscope versus a digital voltmeter?
A. An oscilloscope uses less power
B. Complex impedances can be easily measured
C. Input impedance is much lower?
D. Complex waveforms can be measured

G4B03
How would a signal tracer normally be used?
A. To identify the source of radio transmissions
B. To make exact drawings of signal waveforms
C. To show standing wave patterns on open-wire feed-lines ?
D. To identify an inoperative stage in a receiver

G4B04
How is a noise bridge normally used?
A. It is connected at an antenna's feed point and reads the antenna's noise figure
B. It is connected between a transmitter and an antenna and tuned for minimum SWR ?
C. It is connected between a receiver and an antenna of unknown impedance and is adjusted for minimum noise

D. It is connected between an antenna and ground and tuned for minimum SWR

G4B05
Which of the following is the best instrument to use to check the keying waveform of a CW transmitter? ?
A. A monitoring oscilloscope

B. A field-strength meter
C. A sidetone monitor
D. A wavemeter

G4B06
What signal source is connected to the vertical input of a monitoring oscilloscope when checking the quality of a transmitted signal?
A. The local oscillator of the transmitter
B. The audio input of the transmitter
C. The transmitter balanced mixer output?
D. The attenuated RF output of the transmitter

G4B07
What is an advantage of a digital voltmeter as compared to an analog voltmeter?
A. Better for measuring computer circuits
B. Better for RF measurements?
C. Significantly better precision for most uses

D. Faster response

G4B08
What instrument may be used to monitor relative RF output when making antenna and transmitter adjustments? ?
A. A field-strength meter

B. An antenna noise bridge
C. A multimeter
D. A Q meter

G4B09
How much must the power output of a transmitter be raised to change the "S" meter reading on a distant receiver from S8 to S9?
A. Approximately 2 times
B. Approximately 3 times
C. Approximately 4 times

D. Approximately 5 times

G4B10
Which of the following can be determined with a field strength meter?
A. The radiation resistance of an antenna
B. The radiation pattern of an antenna

C. The presence and amount of phase distortion of a transmitter
D. The presence and amount of amplitude distortion of a transmitter

G4B11
Which of the following might be a use for a field strength meter? ?
A. Close-in radio direction-finding

B. A modulation monitor for a frequency or phase modulation transmitter
C. An overmodulation indicator for a SSB transmitter
D. A keying indicator for a RTTY or packet transmitter

G4B12
What is one way a noise bridge might be used?
A. Determining an antenna's gain in dBi ?
B. Pre-tuning an antenna tuner

C. Pre-tuning a linear amplifier
D. Determining the line loss of the antenna system

G4B13
What is one measurement that can be made with a dip meter??
A. The resonant frequency of a circuit

B. The tilt of the ionosphere
C. The gain of an antenna
D. The notch depth of a filter

G4B14
Which of the following must be connected to an antenna analyzer when it is being used for SWR measurements?
A. Receiver
B. Transmitter ?
C. Antenna and feedline

D. All of these answers are correct

G4B15
Which of the following can be measured with a directional wattmeter??
A. Standing Wave Ratio

B. Antenna front-to-back ratio
C. RF interference
D. Radio wave propagation

G4B16
Why is high input impedance desirable for a voltmeter?
A. It improves the frequency response
B. It decreases battery consumption in the meter
C. It improves the resolution of the readings?
D. It decreases the loading on circuits being measured

G4C - Interference with consumer electronics; grounding

G4C01
Which of the following might be useful in reducing RF interference to audio-frequency devices?
A. Bypass inductor ?
B. Bypass capacitor

C. Forward-biased diode
D. Reverse-biased diode

G4C02
Which of the following should be installed if a properly operating amateur station is interfering with a nearby telephone?
A. An RFI filter on the transmitter ?
B. An RFI filter at the affected telephone

C. A high pass filter on the transmitter
D. A high pass filter at the affected telephone

G4C03
What sound is heard from a public-address system if there is interference from a nearby single-sideband phone transmitter?
A. A steady hum whenever the transmitter is on the air
B. On-and-off humming or clicking
C. Distorted speech

D. Clearly audible speech

G4C04
What is the effect on a public-address system if there is interference from nearby CW transmitter? ?
A. On-and-off humming or clicking

B. A CW signal at a nearly pure audio frequency
C. A chirpy CW signal
D. Severely distorted audio

G4C05
What might be the problem if you receive an RF burn when touching your equipment while transmitting on a HF band, assuming the equipment is connected to a ground rod?
A. Flat braid rather than round wire has been used for the ground wire
B. Insulated wire has been used for the ground wire
C. The ground rod is resonant ?
D. The ground wire is resonant

G4C06
Which of the following is an important reason to have a good station ground?
A. To reduce the likelihood of RF burns
B. To reduce the likelihood of electrical shock
C. To reduce interference ?
D. All of these answers are correct

G4C07
What is one good way to avoid stray RF energy in an amateur station? ?
A. Keep the station's ground wire as short as possible

B. Install an RF filter in series with the ground wire
C. Use a ground loop for best conductivity
D. Install a few ferrite beads on the ground wire where it connects to your station

G4C08
Which of the following is a reason to place ferrite beads around audio cables to reduce common mode RF interference??
A. They act as a series inductor

B. They act as a shunt capacitor
C. They lower the impedance of the cable
D. They increase the admittance of the cable

G4C09
Which of the following statements about station grounding is true?
A. The chassis of each piece of station equipment should be tied together with high-impedance conductors
B. If the chassis of all station equipment is connected with a good conductor, there is no need to tie them to an earth ground ?
C. RF hot spots can occur in a station located above the ground floor if the equipment is grounded by a long ground wire

D. A ground loop is an effective way to ground station equipment

G4C10
Which of the following is covered in the National Electrical Code?
A. Acceptable bandwidth limits
B. Acceptable modulation limits ?
C. Electrical safety inside the ham shack

D. RF exposure limits of the human body

G4C11
Which of the following can cause unintended rectification of RF signal energy and can result in interference to your station as well as nearby radio and TV receivers? ?
A. Induced currents in conductors that are in poor electrical contact

B. Induced voltages in conductors that are in good electrical contact
C. Capacitive coupling of the RF signal to ground
D. Excessive standing wave ratio (SWR) of the transmission line system

G4C12
What is one cause of broadband radio frequency interference at an amateur radio station?
A. Not using a balun or line isolator to feed balanced antennas
B. Lack of rectification of the transmitter's signal in power conductors ?
C. Arcing at a poor electrical connection

D. The use of horizontal, rather than vertical antennas

G4C13
How can a ground loop be avoided?
A. Series connect all ground conductors
B. Connect the AC neutral conductor to the ground wire
C. Avoid using lock washers and star washers in making ground connections ?
D. Connect all ground conductors to a single point

G4D - Speech processors; S meters; common connectors

G4D01
What is the reason for using a properly adjusted speech processor with a single sideband phone transmitter?
A. It reduces average transmitter power requirements
B. It reduces unwanted noise pickup from the microphone
C. It improves voice-frequency fidelity ?
D. It improves signal intelligibility at the receiver

G4D02
Which of the following describes how a speech processor affects a transmitted single sideband signal?
A. It increases the peak power?
B. It increases the average power

C. It reduces harmonic distortion
D. It reduces intermodulation distortion

G4D03
Which of the following can be the result of an incorrectly adjusted speech processor?
A. Distorted speech
B. Splatter
C. Excessive background pickup?
D. All of these answers are correct

G4D04
What does an S-meter measure?
A. Conductance
B. Impedance ?
C. Received signal strength

D. Transmitter power output

G4D05
How does an S-meter reading of 20 db over S-9 compare to an S-9 signal, assuming a properly calibrated S meter?
A. It is 10 times weaker
B. It is 20 times weaker
C. It is 20 times stronger ?
D. It is 100 times stronger

G4D06
Where is an S-meter generally found??
A. In a receiver

B. In a SWR bridge
C. In a transmitter
D. In a conductance bridge

G4D07
Which of the following describes a Type-N connector??
A. A moisture resistant RF connector useful to 10 GHz

B. A small bayonet connector used for data circuits
C. A threaded connector used for hydraulic systems
D. An audio connector used in surround sound installations

G4D08
Which of the following connectors would be a good choice for a serial data port?
A. PL-259
B. Type N
C. Type SMA?
D. DB-9

G4D09
Which of these connector types is commonly used for RF service at frequencies up to 150 MHz?
A. Octal
B. RJ-11?
C. UHF

D. DB-25

G4D10
Which of these connector types is commonly used for audio signals in amateur radio stations?
A. PL-259
B. BNC ?
C. RCA Phono

D. Type N

G4D11
What is the main reason to use keyed connectors over non-keyed types?
A. Prevention of use by unauthorized persons?
B. Reduced chance of damage due to incorrect mating

C. Higher current carrying capacity
D. All of these choices are correct

G4E - HF mobile radio installations; emergency and battery powered operation

G4E01
Which of the following emission types are permissible while operating HF mobile?
A. CW
B. SSB
C. FM?
D. All of these choices are correct

G4E02
What is alternator whine?
A. A DC emission from the alternator
B. A constant pitched tone or buzz in transmitted or received audio that occurs whenever the ignition key is in the on position?
C. A tone or buzz in transmitted or received audio that varies with engine speed

D. A mechanical sound from the alternator indicating current overload

G4E03
Which of the following power connections would be the best for a 100-watt HF mobile installation? ?
A. A direct, fused connection to the battery using heavy gauge wire

B. A direct, fused connection to the alternator or generator using heavy gauge wire
C. A direct, fused connection to the battery using resistor wire
D. A direct, fused connection to the alternator or generator using resistor wire

G4E04
Why is it best NOT to draw the DC power for a 100-watt HF transceiver from an automobile's cigarette lighter socket
A. The socket is not wired with an RF-shielded power cable
B. The socket's wiring may be inadequate for the current being drawn by the transceiver

C. The DC polarity of the socket is reversed from the polarity of modern HF transceivers
D. The power from the socket is never adequately filtered for HF transceiver operation

G4E05
Which of the following most limits the effectiveness of an HF mobile transceiver operating in the 75 meter band?
A. “Picket Fencing” signal variation
B. The wire gauge of the DC power line to the transceiver ?
C. The HF mobile antenna system

D. FCC rules limiting mobile output power on the 75 meter band

G4E06
Which of the following is true of an emergency generator installation??
A. The generator should be located in a well ventilated area

B. The generator should be insulated from ground
C. Fuel should be stored near the generator for rapid refueling in case of an emergency
D. All of these choices are correct

G4E07
When might a lead-acid storage battery give off explosive hydrogen gas?
A. When stored for long periods of time
B. When being discharged ?
C. When being charged

D. When not placed on a level surface

G4E08
What is the name of the process by which sunlight is changed directly into electricity? ?
A. Photovoltaic conversion

B. Photon emission
C. Photosynthesis
D. Photon decomposition

G4E09
What is the approximate open-circuit voltage from a modern, well illuminated photovoltaic cell?
A. 0.02 VDC ?
B. 0.5 VDC

C. 0.2 VDC
D. 1.38 VDC

G4E10
Which of these materials is used as the active element of a solar cell? ?
A. Doped Silicon

B. Nickel Hydride
C. Doped Platinum
D. Aluminum nitride

G4E11
Which of the following is a disadvantage to using wind power as the primary source of power for an emergency station?
A. The conversion efficiency from mechanical energy to electrical energy is less that 2 percent
B. The voltage and current ratings of such systems are not compatible with amateur equipment ?
C. A large energy storage system is needed to supply power when the wind is not blowing

D. All of these choices are correct

G4E12
Which of the following is a primary reason for not placing a gasoline-fueled generator inside an occupied area? ?
A. Danger of carbon monoxide poisoning

B. Danger of engine over torque
C. Lack of oxygen for adequate combustion
D. Lack of nitrogen for adequate combustion

G4E13
Why would it be unwise to power your station by back feeding the output of a gasoline generator into your house wiring by connecting the generator through an AC wall outlet??
A. It might present a hazard for electric company workers

B. It is prone to RF interference
C. It may disconnect your RF ground
D. None of the above; this is an excellent expedient

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