What equipment may be useful to track down EMI aboard a ship or aircraft?

When attempting to track down electromagnetic interference (EMI) aboard a ship or aircraft, a portable AM receiver can be quite useful. An AM receiver can detect radio frequency signals across a wide range of frequencies, allowing it to pick up unwanted interference that may be affecting communication or navigation equipment. By tuning to different frequencies, the operator can identify where the interference is strongest, which aids in pinpointing its source. This capability is especially valuable in the typically noisy environments of ships and aircraft, where multiple electronic devices operate simultaneously.

While the other equipment listed has its respective uses in electronics and signal analysis, it is not specifically designed for tracking down EMI in the way that a portable AM receiver is. A portable RF spectrum analyzer provides a broad analysis of radio frequencies but may be more complex and not as suitable for a straightforward identification task. A multimeter is primarily used for measuring voltage, current, and resistance, and it does not directly help in identifying EMI sources. An oscilloscope, while excellent for visualizing electronic signals, may not effectively detect the type of broadband noise associated with EMI in the context of aviation or maritime operations.