To save work, I'm going to copy and paste a portion of a message I sent to my DX club back in September 2017.  In it I slightly facetiously coined the term "imaginary modes" for the WSJT-X suite and explained it in the footnotes copied here:

"* I call them imaginary because the programs actually decode signals that aren't there (1), or use databases of callsigns as lookup tables to guess received calls (2).

In a discussion I had with one of the FT8 developers about the TX delay in Elecraft radios causing transmission to be delayed until after the decode window opened, he opined that it might not matter because the decoder can "decode" signals that it never heard.

(1) Quoting G4WJS: "For FT8 the net effect is that
up to about 5 seconds of a message may be missing yet still
be decoded. The amount missing can be either a truncation or
parts of the message below the decoding threshold. The FT8
message is structured with sync symbols at the start, middle
and end so missing the start or end may have less impact
than missing other parts since mostly sync symbols may be
lost and they contain no message information."

(2) Another compelling paper discusses JT65 as used on EME. "

 So not to worry, your computers can continue to work each other without worrying about VOX delay.

Wes  N7WS
On 2/23/2018 7:57 AM, Bob McGraw K4TAX wrote:
My concern with using VOX is that the radio has to receive audio before it goes into transmit.  Thus one can almost be assured some data will be lost.   Hence I find the better PTT choice is CAT with a 0.1 second TX delay before audio is sent to the radio from the software.  This is all available from the F2 Setup menu in WSJT-X.


Bob, K4TAX

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