Introduction to WSJT-X FT8

FT8 is a new mode included in WSJT-X versions 1.8 and later.

This weak signal mode is intended—and optimised—for making efficient barebones contacts; a definite plus during this time of poor propagation. Although FT8 does not support rag-chewing or contesting exchanges it is, none the less, well worth trying out in the Amateur Radio spirit of learning and experimentation.

The slides from my presentation after the adjournment of the April 17, 2018, RRRA Business Meeting are available for download from the Training and Education | Presentations folder on the RRRA File Sharing server.

About FT8

The new mode is named after its developers, Steven Franke, K9AN, and Joe Taylor, K1JT. The numeral designates the mode’s 8-frequency shift keying format. Tones are spaced at 6.25 Hz, and an FT8 signal occupies just 50 Hz. Unlike JT65 or JT9, transmit and receive cycles in FT8 each last about 15 seconds. Like JT65, FT8 requires accurate time synchronization. An auto-sequencing feature offers the option to respond automatically to the first decoded reply to your CQ.

“FT8 is an excellent mode for HF DXing and for situations like multi-hop Es on 6 meters, where deep QSB may make fast and reliable completion of QSOs desirable,” Taylor’s release notes assert. 1


  1. “FT8 Mode is Latest Bright Shiny Object in Amateur Radio Digital World”, ARRL The national association for Amateur Radio, retrieved April 18 2018, http://www.arrl.org/news/ft8-mode-is-latest-bright-shiny-object-in-amateur-radio-digital-world. [return]