FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T7B09

From subelement T7 - T7B

T7B09
Answer: D

What should be the first step to resolve non-fiber optic cable TV interference caused by your amateur radio transmission?

AAdd a low-pass filter to the TV antenna input
BAdd a high-pass filter to the TV antenna input
CAdd a preamplifier to the TV antenna input
DBe sure all TV feed line coaxial connectors are installed properly

Why is this correct?

Before adding filters or amplifiers, check the most common cause: loose or improperly installed coaxial connectors. Poor connections allow your RF signal to leak into the cable system, causing interference. Options A, B, and C involve adding equipment, but loose connectors are the primary culprit in cable TV interference cases. Always start with the simplest, most likely cause.

Memory tip

Follow the troubleshooting principle: check physical connections before adding components. Cable TV systems are designed to be well-shielded, so interference usually means RF is getting in through poor connections rather than inadequate filtering.

Learn more

Cable TV interference typically occurs when amateur signals enter through compromised cable integrity rather than inadequate receiver selectivity. Properly installed F-connectors with tight connections prevent signal ingress. The cable system's own shielding specifications under Part 76 are designed to reject external RF when connections maintain system integrity. Missing terminators on unused outlets also create entry points for unwanted signals.

Think about it

Why do you think loose connectors would be more problematic for cable TV systems than for over-the-air TV reception?