Which instrument is most appropriate for checking continuity in a circuit?

• A. Spectrum Analyzer
• B. NEXRAD
• C. Bit Error Rate Test Set
• D. Multimeter

Answer: (A)

Continuity means there is a complete path for current between two points. To verify that, a multimeter used in continuity or resistance mode is the best tool. It applies a small test current and measures the resistance of the path; a low reading or an audible beep indicates the circuit is continuous, while a high or infinite resistance shows an open or broken connection. This makes the multimeter the go-to instrument for checking wires, traces, and connections.

The other devices serve different purposes. A spectrum analyzer analyzes the frequency content of signals, not whether a path conducts. NEXRAD is a weather radar system, not a general circuit tester. A Bit Error Rate Test Set evaluates data integrity on digital links, not the physical continuity of a circuit. Always ensure the circuit is powered down and capacitors are discharged before testing.