Cabling best practices: If a parallel/USB printer cable is routed too close to an AC power cable, which problem is most likely?

Introduction / Context:
Power cables carrying alternating current create time-varying electromagnetic fields. Signal cables placed too close can pick up noise, reducing signal integrity. Understanding this helps with printer setup, AV gear, and general PC cabling.

Given Data / Assumptions:

• Printer data cable runs parallel and adjacent to an AC mains cable.
• No special shielding or ferrite chokes are assumed.
• Symptoms could include intermittent printing, corrupted jobs, or device resets.

Concept / Approach:

Coupling between cables occurs via electric (capacitive) and magnetic (inductive) mechanisms. The coupled noise is termed electromagnetic interference (EMI). To mitigate, separate power and data paths, cross at right angles, shorten runs, or use shielded cables and ferrite beads.

Step-by-Step Solution:

Verification / Alternative check:

Re-route the cable away from power lines or add ferrites; if symptoms disappear, EMI was the cause. Oscilloscope probing can also reveal coupled noise spikes during load changes on the AC line.

Why Other Options Are Wrong:

• ESD: Static shock events, not continuous coupling from adjacent power.
• Parity error: Memory/storage concept, not cabling interference terminology.
• No affect: Contrary to known coupling effects.
• None of the above: Incorrect because EMI is correct.

Common Pitfalls:

Bundling all cables in a single tie for neatness; using excessively long unshielded leads; ignoring ground loops when using shielded cables.

Final Answer:

EMI Electromagnetic Interference