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Section 3 25 q65
Choose Q65 from the DIGITAL row. Q65 is the modern WSJT weak-signal mode: a 65-tone signal built for the paths where FT8 and JT65 run out — EME (moonbounce), ionoscatter, rainscatter and troposcatter — and the mode WSJT-X recommends for 6 m and up. It is more sensitive than JT65 and, unlike the older JT modes, carries a CRC, so a decode is checksummed rather than a claim.
The sub-mode is the setting. Q65 has two independent axes, and the chip row at the top of the panel picks the combination. The T/R period is 15, 30, 60, 120 or 300 seconds, and the tone-spacing letter (A–E) widens the signal — A is the narrow, sensitive terrestrial choice; E tolerates the most Doppler spread for fast-fading microwave paths. Q65-60A (60-second period, letter A) is the band convention and the default. Both ends of a contact have to agree, so check what the other station is running. Ten sub-modes are wired here: 15A, 30A, 60A–60E, 120D, 120E and 300A.
What you see. The same DECODES list as JT65/JT9 and FST4 — time, SNR,
audio offset, and the decoded <to> <from> <grid|report>. Q65 carries the same
77-bit message as FT8.
One slot at a time, and a long one. The decoder holds the whole slot and decodes it on a worker thread — a Q65-300 scan is tens of seconds of work over a five-minute slot — so on the longer sub-modes expect the list to fill in well after the period ends, and a slot to be skipped rather than queued if the machine cannot keep up.
Receive only. As with JT65/JT9 and FST4, transmit is not wired in this build: a Q65 contact is a precisely-timed, minutes-long handshake and the panel decodes rather than sequences.
From the User Manual. Home.