SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/hame-ft8-15s

How long is one FT8 transmit/receive sequence?

15 seconds per T/R sequence.

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  1. 7.5 seconds
  2. 2 minutes
  3. 15 seconds ✔

Why: FT8 uses 15-second transmit/receive sequences, which keeps contacts fast. The trade is a few dB less sensitivity than slower WSJT modes.

Huh, didn't know that: FT4 is faster still, with 7.5-second sequences, and is especially well suited to contesting.

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References

Answer: 15 seconds. FT8 uses 15-second transmit/receive sequences, which keeps contacts fast. The trade is a few dB less sensitivity than slower WSJT modes.

  1. WSJT-X User Guide 2.7.0, Introduction wsjt.sourceforge.io/wsjtx-doc/wsjtx-main-2.7.0.html
    FT8 is four times faster (15-second T/R sequences)
    Checked 2026-10-11.
  2. WSJT-X User Guide 2.7.0, Introduction wsjt.sourceforge.io/wsjtx-doc/wsjtx-main-2.7.0.html
    FT4 is faster still (7.5 s T/R sequences)
    Checked 2026-10-11.

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