SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hamg-ft8-clock

Which of these is required to operate FT8?

Your computer clock, within about 1 second.

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  1. A vertically polarized antenna
  2. Computer time within about 1 second ✔
  3. A special hardware modem

Why: FT8 stations take turns in fixed time slots, so every clock must agree. If yours is far off, you can't decode others or be decoded.

Huh, didn't know that: Common FT8 activity on 20 meters is near 14.074 to 14.077 MHz.

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You know you're a ham when your watch is set only to UTC.
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References

Answer: Computer time within about 1 second. FT8 stations take turns in fixed time slots, so every clock must agree. If yours is far off, you can't decode others or be decoded.

  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
    Computer time accurate to within approximately 1 second
    Checked 2026-10-10.

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