SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-g5b01

About how many dB represents a factor of two increase or decrease in power?

About 3 dB doubles or halves power.

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  1. About 3 dB ✔
  2. About 2 dB
  3. About 6 dB

Why: Every 3 dB doubles the power, and every 3 dB of loss cuts it in half. So 6 dB is four times the power, not double.

Huh, didn't know that: A 100 watt signal that loses 3 dB is down to about 50 watts.

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Why do electrical engineers love power naps? You can build up a charge with them.
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References

Answer: About 3 dB. Every 3 dB doubles the power, and every 3 dB of loss cuts it in half. So 6 dB is four times the power, not double.

  1. NCVEC 2023-2027 General Class Pool and Syllabus (6th Errata, Feb 4 2026) ncvec.org/downloads/General%20Class%20Pool%20and%20Syllabus%202023-2027%20Public%20Release%20with%206th%20Errata%20Feb%204%202026.pdf
    Approximately 3 dB
    Checked 2026-10-11.

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