Which test instrument is used when testing the main rotor leads?

The use of a multimeter set to ohms is appropriate for testing the main rotor leads because it measures electrical resistance. In this context, you want to check the continuity and integrity of the rotor leads—the absence of inefficient connections, shorts, or opens. By measuring the resistance of the leads, you can determine whether the circuit is complete and functioning properly. This is crucial for ensuring safety and performance in systems where the rotor leads play a vital role.

An oscilloscope, while useful for visualizing waveforms and assessing signal behavior, is not designed for resistance measurements. A voltammeter is typically involved in measuring current and voltage but doesn't test resistance. A frequency meter is used for measuring the frequency of an electrical signal, which is not relevant when assessing the condition of main rotor leads.