Practical takeaway
Voltmeters, ammeters, ohmmeters, multimeters, safe measurement, and basic soldering.
T7D · 11 pool questions
Meters, Measurement & Soldering
Voltmeters, ammeters, ohmmeters, multimeters, safe measurement, and basic soldering.
Technician exam focus
This group contains 11 questions in the current pool. The teaching below keeps the important tested terms visible while explaining what they mean in normal Amateur Radio use.
1. Measure voltage in parallel
Electric potential is voltage, so use a voltmeter. Connect it in parallel across the component or two points whose voltage difference you want to measure.
2. Measure current in series
An ammeter must be connected in series so the circuit current passes through the meter. Putting an ammeter directly across a voltage source can create a near-short and blow the meter fuse or damage the meter.
3. Resistance measurements need power off
An ohmmeter/multimeter on the resistance range supplies its own small test current. Do not try to measure voltage while the meter is set to resistance, and normally make resistance measurements with the circuit de-energized.
4. Solder electronics with the right materials and heat
Use solder intended for electronics, commonly rosin-flux solder; acid-core solder should not be used for electronic/radio work because the corrosive flux can damage conductors. Heat the connection enough for solder to flow and wet the joint rather than piling solder onto a cold surface.
T7D checklist
- Voltmeter: voltage/electric potential; connect in parallel.
- Ammeter: current; connect in series.
- A multimeter commonly measures voltage, current, and resistance.
- Do not apply external voltage while the meter is on the resistance setting.
- Do not place an ammeter directly across a voltage source.
- Avoid acid-core solder for electronics; make clean, properly heated joints.
Exam scope: NCVEC 2026–2030 Technician Class (Element 2), effective July 1, 2026 through June 30, 2030, with February 19, 2026 errata. The current NCVEC pool is the exam authority; explanatory prose here is SPARKA teaching material. NCVEC pool