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SESK: Stuff Everyone Should Know · sesk.info/ham-low-power-high-swr

What might cause low RF power output from a solid-state transceiver?

High SWR can cause low power output.

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  1. Low SWR
  2. Poor amplifier noise figure
  3. High SWR ✔

Why: When SWR is high, solid-state radios turn their power down to protect themselves. If your output is low, check the antenna and feed line.

Huh, didn't know that: A loose connector or damaged coax can raise SWR suddenly.

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My radio's power dropped when the SWR went up. It said it needed some space.
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References

Answer: High SWR. When SWR is high, solid-state radios turn their power down to protect themselves. If your output is low, check the antenna and feed line.

  1. NCVEC 2026-2030 Technician Question Pool (February 19, 2026 errata) ncvec.org/downloads/2026-2030%20Technician%20Pool%20and%20Syllabus%20Public%20Release%20Feb%2019%202026.pdf
    D. High SWR
    Checked 2026-10-09.

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