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 *FT8 and MSK144: NA VHF Contest Mode* to enable generation and
auto-sequencing of messages using four-character grid locators in
place of signal reports, as required for most North American VHF
contests.

- Check *x 2 Tone spacing* to generate Tx audio with twice the normal
tone spacing.  This feature is intended for use with specialized LF/MF
transmitters that divide the audio waveform by 2 before further
processing.