General exam question G0A07
Subelement G0, ELECTRICAL AND RF SAFETY· Group G0A
What is the effect of modulation duty cycle on RF exposure?
- A.A lower duty cycle permits greater power levels to be transmitted (correct answer)
- B.A higher duty cycle permits greater power levels to be transmitted
- C.Low duty cycle transmitters are exempt from RF exposure evaluation requirements
- D.High duty cycle transmitters are exempt from RF exposure requirements
WhyA lower modulation duty cycle permits greater power levels to be transmitted within the same RF exposure limit. Because time-averaged exposure is what matters, a signal that transmits less of the time (a lower duty cycle) delivers less average RF energy for a given peak power, which is exactly why lower-duty-cycle modes are allowed to run at higher power levels within the same exposure limit, answer A. A higher duty cycle requires lower power to stay within the same average-exposure limit, not higher, and duty cycle affects the power level permitted rather than exempting any transmitter outright from evaluation, so B, C, and D are wrong.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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