What can cause excessive return loss?

• A. Impedance mismatch
• B. Substandard components
• C. Improper terminations
• D. All of the above

Answer: (D)

Excessive return loss happens when energy traveling down a copper path is reflected back toward the source due to impedance changes along the path. Any place where the line’s impedance isn’t consistent or properly terminated creates reflections. Impedance mismatch occurs when different sections or components don’t share the same characteristic impedance, causing part of the signal to bounce back. Substandard components can introduce unexpected impedance variances or weak connections, adding reflections along the link. Improper terminations—such as connectors or terminations not seated correctly or the wrong type—cause a sudden impedance change at that point. All of these situations produce more reflected signal, so they all contribute to higher return loss.