Technician T7D: Meters and soldering
These are the 11 official questions in group T7D of the 2026–2030 Technician question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- T7D01Question 1
Which instrument would you use to measure electric potential?
- AAn ammeter
- BA voltmeter Correct
- CA potentiometer
- DAn ohmmeter
Why: A voltmeter measures electric potential (voltage).
- T7D02Question 2
How is a voltmeter connected to a component to measure applied voltage?
- AIn series
- BIn parallel Correct
- CIn quadrature
- DIn phase
Why: A voltmeter goes in parallel, across the component.
- T7D03Question 3
When configured to measure current, how is a multimeter connected to a component?
- AIn series Correct
- BIn parallel
- CIn quadrature
- DIn phase
Why: To measure current, a meter goes in series so the current flows through it.
- T7D04Question 4
Which instrument is used to measure electric current?
- AAn ohmmeter
- BAn electrometer
- CA voltmeter
- DAn ammeter Correct
Why: An ammeter measures current.
- T7D05Question 5
How does an ohmmeter measure the resistance of a circuit or component?
- ABy applying a small current and measuring the resulting voltage Correct
- BBy placing a variable resistor in parallel with the circuit
- CBy placing a variable resistor in series with the circuit
- DBy applying a variable voltage and measuring the resulting current change
Why: An ohmmeter applies a small current and measures the voltage to work out resistance.
- T7D06Question 6
Which of the following can damage a multimeter?
- AAttempting to measure resistance using the voltage setting
- BFailing to connect one of the probes to ground
- CAttempting to measure voltage when using the resistance setting Correct
- DNot allowing it to warm up properly
Why: Measuring voltage while on the resistance setting can damage the meter.
- T7D07Question 7
Which of the following measurements are made using a multimeter?
- ASignal strength and noise
- BImpedance and reactance
- CVoltage and resistance Correct
- DAll these choices are correct
Why: A multimeter measures voltage and resistance (and usually current too).
- T7D08Question 8
Which of the following types of solder should not be used for radio and electronic applications?
- AAcid-core solder Correct
- BLead-tin solder
- CRosin-core solder
- DTin-copper solder
Why: Acid-core solder corrodes electronic connections. Use rosin core.
- T7D09Question 9
What is the characteristic appearance of a cold tin-lead solder joint?
- ADark black spots
- BA bright or shiny surface
- CA rough or lumpy surface Correct
- DA greenish tinge
Why: A cold solder joint looks rough or lumpy instead of smooth and shiny.
- T7D10Question 10
What reading indicates that an ohmmeter is connected across a large, discharged capacitor?
- AIncreasing resistance with time Correct
- BDecreasing resistance with time
- CSteady full-scale reading
- DAlternating between open and short circuit
Why: The ohmmeter's current charges the capacitor, so the resistance reading climbs over time.
- T7D11Question 11
Which of the following precautions should be taken when measuring in-circuit resistance with an ohmmeter?
- AEnsure that the applied voltages are correct
- BEnsure that the circuit is not powered Correct
- CEnsure that the circuit is grounded
- DEnsure that the circuit is operating at the correct frequency
Why: Make sure the circuit is off. Voltage in the circuit gives false readings and can harm the meter.