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technician pool

Subelement T4 question review

All 23 official questions with the exact winning phrase marked.

T4A01T4A

Which of the following is an appropriate power supply rating for a typical 50-watt output mobile FM transceiver?

D13.8 volts at 12 amperes
Why this answer

The key fact is 13.8 volts at 12 amperes. 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
T4A02T4A

Which of the following should be considered when selecting an accessory SWR meter?

AThe frequency and power level at which the measurements will be made
Why this answer

The key fact is The frequency and power level at which the measurements will be made. 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.

T4A03T4A

Why are short, heavy-gauge wires used for a transceiver’s DC power connection?

ATo minimize voltage drop when transmitting
Why this answer

The reason is to minimize voltage drop when transmitting. Connect the cause in the question to this direct result instead of memorizing the answer letter.

P = E × I
T4A04T4A

How are the audio input and output of a transceiver connected in a station configured to operate using FT8?

BTo the audio output and input of a computer running FT8 software
Why this answer

Use this action or method: To the audio output and input of a computer running FT8 software. It is the choice that directly completes the job described in the question.

T4A05T4A

Where should an RF power meter be installed?

AIn the feed line, between the transmitter and antenna
Why this answer

The key fact is In the feed line, between the transmitter and antenna. 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.

P = E × I
T4A06T4A

What signals are used in a computer-radio interface for digital mode operation?

CReceive audio, transmit audio, and transmitter keying
Why this answer

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

T4A07T4A

Which of the following is one of the connections required between a computer and a transceiver to operate digital modes?

CComputer “line in” to transceiver speaker connector
Why this answer

The key fact is Computer “line in” to transceiver speaker connector. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4A08T4A

Which of the following conductors is preferred for bonding at RF?

DFlat copper strap
Why this answer

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

T4A09T4A

How can you determine the length of time that equipment can be powered from a battery?

BDivide the battery ampere-hour rating by the average current draw of the equipment
Why this answer

Use this action or method: Divide the battery ampere-hour rating by the average current draw of the equipment. It is the choice that directly completes the job described in the question.

P = E × I
T4A10T4A

What function does a digital mode hotspot perform for nearby transceivers?

ACommunication with a digital voice or data network
Why this answer

The key fact is Communication with a digital voice or data network. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4A11T4A

Where should the negative power return of a mobile transceiver be connected in a vehicle?

AAt the 12-volt battery chassis ground
Why this answer

The key fact is At the 12-volt battery chassis ground. 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.

P = E × I
T4A12T4A

What is an electronic keyer?

CA device that assists in manual sending of Morse code
Why this answer

The key fact is A device that assists in manual sending of Morse code. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4B01T4B

What is the effect of excessive microphone gain on SSB transmissions?

BDistorted transmitted audio
Why this answer

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

T4B02T4B

Which of the following can be used to enter a transceiver’s operating frequency?

AThe keypad or VFO knob
Why this answer

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

T4B03T4B

How is squelch adjusted so that a weak FM signal can be heard?

ASet the squelch threshold so that receiver output audio is on all the time
Why this answer

Use this action or method: Set the squelch threshold so that receiver output audio is on all the time. It is the choice that directly completes the job described in the question.

T4B04T4B

What does an FM signal sound like when received slightly off frequency?

DThe audio becomes distorted
Why this answer

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

T4B05T4B

What does the scanning function of an FM transceiver do?

CTunes through a range of frequencies to check for activity
Why this answer

The key fact is Tunes through a range of frequencies to check for activity. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4B06T4B

Which of the following controls could be used if the voice pitch of a single-sideband signal returning to your CQ call seems too high or low?

DThe RIT or Clarifier
Why this answer

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

T4B07T4B

What is a DMR “code plug”?

BConfiguration data loaded onto your radio to access repeaters and talkgroups
Why this answer

The key fact is Configuration data loaded onto your radio to access repeaters and talkgroups. 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.

T4B08T4B

What is the advantage of having a choice of receiver filter bandwidths in a multimode transceiver?

BPermits noise or interference reduction by selecting a bandwidth matching the mode
Why this answer

The key fact is Permits noise or interference reduction by selecting a bandwidth matching the mode. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4B09T4B

How is a specific group of stations selected on a DMR digital voice transceiver?

CBy entering the group’s identification code
Why this answer

Use this action or method: By entering the group’s identification code. It is the choice that directly completes the job described in the question.

T4B10T4B

Which of the following receiver filter bandwidths provides the best signal-to-noise ratio for SSB reception?

C2400 Hz
Why this answer

The key fact is 2400 Hz. Match that fact to the exact condition in the question; the other choices describe a different rule, band, component, or operating situation.

T4B11T4B

Which of the following must be programmed into a D-STAR digital transceiver before transmitting?

AYour call sign
Why this answer

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

Memory hook: Identify clearly and at the required interval.