Не путайте FST4 с FT4, у которого совсем другое предназначение! FST4 предназначен для проведения двусторонних QSO на LF и MF диапазонах.
FST4-15A, -30B, -30C, -30D Fast (contest?) EME QSOs on 144 – 1296 MHz ?
FST4-120B, -120C, -300C, -300D EME on 50, 144, 432 MHz with weakest possible signals
EME on VHF and UHF bands with T/R sequences both shorter and longer than 60 s
… but other uses will surely be found, as well. We expect that FST4 will serve some of its intended
purposes better than older modes in WSJT-X, and without the strict time- and frequency-locking
requirements of modes such as EbNaut. Интересно про отсутствие жёсткой привязки к частотной и временной синхронизации.Источник:Steve Franke, K9AN; Bill Somerville, G4WJS; and Joe Taylor, K1JT
Version 2.3 of WSJT-X introduces a new family of digital modes we designate FST41