WSJT-X/doc/user_guide/en/settings-advanced.adoc

image::settings-advanced.png[align="center",alt="Settings Advanced"]

_JT65 decoding parameters_ 

- *Random erasure patterns* logarithmically scales the number of
pseudo-random trials used by the Franke-Taylor JT65 decoder.  Larger
numbers give slightly better sensitivity but take longer.  For most
purposes a good setting is 6 or 7.

- *Aggressive decoding level* sets the threshold for acceptable
decodes using Deep Search.  Higher numbers will display results 
with lower confidence levels.

- Check *Two-pass decoding* to enable a second decoding pass after
signals producing first-pass decodes have been subtracted from the
received data stream.

_Miscellaneous_

- Set a positive number in *Degrade S/N of .wav file* to add known
amounts of pseudo-random noise to data read from a .wav file.  To
ensure that the resulting S/N degradation is close to the requested
number of dB, set *Receiver bandwidth* to your best estimate of the
receiver's effective noise bandwidth.

- Set *Tx delay* to a number larger than the default 0.2 s to create
a larger delay between execution of a command to enable PTT and onset
of Tx audio.  

IMPORTANT: For the health of your T/R relays and external
preamplifier, we strongly recommend using a hardware sequencer and
testing to make sure that sequencing is correct.

- Check *x 2 Tone spacing* or *x 4 Tone spacing* to generate Tx audio
with twice or four times the normal tone spacing.  This feature is
intended for use with specialized LF/MF transmitters that divide
generated frequencies by 2 or 4 as part of the transmission process.

_Special Operating Activity: Generation of FT8 and MSk144 messages_

- Check this box and select the type of activity to enable
auto-generation of special message formats for contesting and
DXpeditions.  For *ARRL Field Day*, enter your operating Class and
ARRL/RAC section; for *ARRL RTTY Roundup*, enter your state or province.
Use “DX” for section or state if you are not in the US or Canada.  In
the RTTY Roundup, Stations in Alaska and Hawaii should enter “DX”.

- Check *Fox* if you are a DXpedition station operating in FT8
DXpedition Mode.  Check *Hound* if you wish to make QSOs with such a
Fox.  Be sure to read the operating instructions for {ft8_DXped}.