跳过主要内容

technician pool

Subelement T7 question review

All 44 official questions with the exact winning phrase marked.

T7A01T7A

Which term describes the ability of a receiver to detect the presence of a signal?

BSensitivity
Why this answer

The key fact is Sensitivity. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A02T7A

What is a transceiver?

AA device that combines a receiver and transmitter
Why this answer

The key fact is A device that combines a receiver and transmitter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A03T7A

Which of the following is used to convert a signal from one frequency to another?

BMixer
Why this answer

The key fact is Mixer. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A04T7A

Which term describes the ability of a receiver to discriminate between multiple signals?

CSelectivity
Why this answer

The key fact is Selectivity. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A05T7A

What is the name of a circuit that generates a signal at a specific frequency?

DOscillator
Why this answer

The key fact is Oscillator. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A06T7A

What device converts the RF input and output of a transceiver to another band?

CTransverter
Why this answer

The key fact is Transverter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A07T7A

What is the function of a transceiver’s PTT input?

BSwitches transceiver from receive to transmit when grounded
Why this answer

The key fact is Switches transceiver from receive to transmit when grounded. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Ground paths should be short, direct, and bonded together.

T7A08T7A

Which of the following describes combining speech with an RF carrier signal?

CModulation
Why this answer

The key fact is Modulation. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7A09T7A

What is the function of the switch which selects either SSB or CW-FM on some VHF power amplifiers?

BSet the amplifier for proper operation in the selected mode
Why this answer

The key fact is Set the amplifier for proper operation in the selected mode. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I
T7A10T7A

What can be added to the output of a transceiver to increase the transmitted output power?

BAn RF power amplifier
Why this answer

The key fact is An RF power amplifier. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I
T7A11T7A

What is the function of the Variable Frequency Oscillator (VFO) circuit in a transceiver?

ASet the receive and transmit frequency
Why this answer

The key fact is Set the receive and transmit frequency. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B01T7B

What can you do if you are told your FM handheld or mobile transceiver is over-deviating?

DTalk farther away from the microphone
Why this answer

The key fact is Talk farther away from the microphone. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B02T7B

What would cause a broadcast AM or FM radio to receive an amateur radio transmission unintentionally?

AThe receiver is unable to reject strong signals outside the AM or FM band
Why this answer

The key fact is The receiver is unable to reject strong signals outside the AM or FM band. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B03T7B

Which of the following can cause radio frequency interference?

DAll these choices are correct
Why this answer

The key fact is All these choices are correct. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B04T7B

Which of the following might be the cause of low RF power output from a solid-state transceiver?

DHigh SWR
Why this answer

The key fact is High SWR. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Lower SWR means the feed line and load are better matched.

P = E × I
T7B05T7B

Which of the following might reduce interference by an amateur station to a non-amateur over-the-air radio receiver?

ABlock the amateur signal with a filter at the antenna input of the affected receiver
Why this answer

The key fact is Block the amateur signal with a filter at the antenna input of the affected receiver. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: A half wave dipole is two quarter wave legs.

T7B06T7B

Which of the following actions should you take if a neighbor tells you that your station’s transmissions are interfering with their radio or TV reception?

AMake sure that your station is functioning properly and that it does not cause interference to your own radio or television when it is tuned to the same channel
Why this answer

The key fact is Make sure that your station is functioning properly and that it does not cause interference to your own radio or television when it is tuned to the same channel. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B07T7B

Which of the following can reduce interference to a 2-meter band transceiver from a nearby commercial FM station?

DInstalling a band-reject filter
Why this answer

The key fact is Installing a band-reject filter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B08T7B

What should you do if something in a neighbor’s home is causing harmful interference to your amateur station?

DAll these choices are correct
Why this answer

The key fact is All these choices are correct. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B09T7B

What should be the first step to resolve non-fiber optic cable TV interference caused by your amateur radio transmission?

DBe sure all TV feed line coaxial connectors are installed properly
Why this answer

The key fact is Be sure all TV feed line coaxial connectors are installed properly. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7B10T7B

What might be a problem if you receive a report that your audio signal through an FM repeater is distorted or unintelligible?

DAll these choices are correct
Why this answer

The key fact is All these choices are correct. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: A repeater receives on one frequency and transmits on another.

T7B11T7B

Which of the following can eliminate distorted voice transmissions?

CAdding a clip-on ferrite “choke” to the microphone cable to prevent the transmitted signal from feeding back into the transmitter
Why this answer

The key fact is Adding a clip-on ferrite “choke” to the microphone cable to prevent the transmitted signal from feeding back into the transmitter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7C01T7C

What is the primary purpose of a dummy load?

ATo prevent transmitting signals over the air when making tests
Why this answer

The key fact is To prevent transmitting signals over the air when making tests. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7C02T7C

Which of the following is used to determine if an antenna is resonant at the desired operating frequency?

BAn antenna analyzer
Why this answer

The key fact is An antenna analyzer. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: A half wave dipole is two quarter wave legs.

T7C03T7C

What does a typical RF dummy load consist of?

BA 50-ohm non-inductive resistor mounted on a heat sink
Why this answer

The key fact is A 50-ohm non-inductive resistor mounted on a heat sink. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7C04T7C

What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?

C1:1
Why this answer

The key fact is 1:1. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: A half wave dipole is two quarter wave legs.

T7C05T7C

Why do most solid-state transmitters reduce output power as SWR increases beyond a certain level?

ATo protect the RF output amplifier transistors
Why this answer

The reason is to protect the RF output amplifier transistors. Connect the cause in the question to this direct result instead of memorizing the answer letter.

Memory hook: Lower SWR means the feed line and load are better matched.

P = E × I
T7C06T7C

What does an SWR reading of 4:1 indicate?

DImpedance mismatch
Why this answer

The key fact is Impedance mismatch. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Lower SWR means the feed line and load are better matched.

T7C07T7C

What happens to power lost in a feed line?

CIt is converted into heat
Why this answer

The key fact is It is converted into heat. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

P = E × I
T7C08T7C

Which instrument can be used to determine SWR?

DDirectional wattmeter
Why this answer

The key fact is Directional wattmeter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Lower SWR means the feed line and load are better matched.

T7C09T7C

Which of the following causes failure of coaxial cables?

AMoisture contamination
Why this answer

The key fact is Moisture contamination. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7C10T7C

Why should the outer jacket of coaxial cable be resistant to ultraviolet light?

DUltraviolet light can damage the jacket and allow water to enter the cable
Why this answer

The reason is ultraviolet light can damage the jacket and allow water to enter the cable. Connect the cause in the question to this direct result instead of memorizing the answer letter.

T7C11T7C

What is an advantage of foam-dielectric versus solid-dielectric coaxial cable?

CIt has less loss per foot
Why this answer

The key fact is It has less loss per foot. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D01T7D

Which instrument would you use to measure electric potential?

BA voltmeter
Why this answer

The key fact is A voltmeter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D02T7D

How is a voltmeter connected to a component to measure applied voltage?

BIn parallel
Why this answer

Use this action or method: In parallel. It is the choice that directly completes the job described in the question.

E = I × R
T7D03T7D

When configured to measure current, how is a multimeter connected to a component?

AIn series
Why this answer

The key fact is In series. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

E = I × R
T7D04T7D

Which instrument is used to measure electric current?

DAn ammeter
Why this answer

The key fact is An ammeter. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

E = I × R
T7D05T7D

How does an ohmmeter measure the resistance of a circuit or component?

ABy applying a small current and measuring the resulting voltage
Why this answer

Use this action or method: By applying a small current and measuring the resulting voltage. It is the choice that directly completes the job described in the question.

E = I × R
T7D06T7D

Which of the following can damage a multimeter?

CAttempting to measure voltage when using the resistance setting
Why this answer

The key fact is Attempting to measure voltage when using the resistance setting. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D07T7D

Which of the following measurements are made using a multimeter?

CVoltage and resistance
Why this answer

The key fact is Voltage and resistance. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D08T7D

Which of the following types of solder should not be used for radio and electronic applications?

AAcid-core solder
Why this answer

The key fact is Acid-core solder. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D09T7D

What is the characteristic appearance of a cold tin-lead solder joint?

CA rough or lumpy surface
Why this answer

The key fact is A rough or lumpy surface. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T7D10T7D

What reading indicates that an ohmmeter is connected across a large, discharged capacitor?

AIncreasing resistance with time
Why this answer

The key fact is Increasing resistance with time. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

Memory hook: Capacitors store energy in an electric field.

E = I × R
T7D11T7D

Which of the following precautions should be taken when measuring in-circuit resistance with an ohmmeter?

BEnsure that the circuit is not powered
Why this answer

The key fact is Ensure that the circuit is not powered. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

E = I × R