FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T7B03

From subelement T7 - T7B

T7B03
Answer: D

Which of the following can cause radio frequency interference?

AFundamental overload
BHarmonics
CSpurious emissions
DAll these choices are correct

Why is this correct?

All three options cause radio frequency interference through different mechanisms. Fundamental overload occurs when your strong amateur signal overwhelms a receiver's ability to reject signals outside its intended band. Harmonics are multiples of your fundamental frequency that can interfere with other services. Spurious emissions are unwanted signals at random frequencies caused by poor transmitter design or operation. Each represents a distinct pathway for amateur signals to disrupt non-amateur equipment.

Memory tip

When facing 'all choices correct' questions, systematically verify each option independently rather than looking for the 'best' single answer. This pattern appears frequently in interference troubleshooting questions where multiple technical causes can produce similar symptoms.

Learn more

Radio frequency interference manifests through three primary emission categories defined in Part 97: fundamental signals exceeding receiver dynamic range, harmonic emissions violating spurious emission standards, and other spurious emissions outside authorized frequency privileges. Understanding these categories helps operators implement appropriate filtering, power control, and station design practices to maintain good amateur practice and minimize interference to other radio services and consumer electronics.

Think about it

Why do you think the FCC requires amateur operators to take responsibility for all three types of interference, even when the affected device might have poor design or inadequate filtering?