Extra exam question E4B05
Subelement E4, AMATEUR PRACTICES· Group E4B
What three test loads are used to calibrate an RF vector network analyzer?
- A.50 ohms, 75 ohms, and 90 ohms
- B.Short circuit, open circuit, and 50 ohms (correct answer)
- C.Short circuit, open circuit, and resonant circuit
- D.50 ohms through 1/8 wavelength, 1/4 wavelength, and 1/2 wavelength of coaxial cable
WhyCalibrating an RF vector network analyzer typically uses three test loads: a short circuit, an open circuit, and a 50 ohm termination. Calibrating an RF vector network analyzer's port typically uses three known reference loads: a short circuit, an open circuit, and a precision 50 ohm termination, giving the analyzer three well-defined reflection points to build its error-correction model from, answer B. The other combinations, mismatched resistive loads, a resonant circuit, or specific lengths of coaxial cable, aren't the standard calibration set a VNA uses.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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