[wsjt-devel] JT4 incorrect SNR reports (introduced in wsjtx-2.1.0-rc5)

[Dawid S. <sq...@ha...>]

Hey, for some time I have been playing a lot with JT4(g).
During those exercises it was identified that JT4(g) - I was only playing
with G is incorrectly reporting the SNR (meaning values are never stronger
than -13dB and there is no even indirect connection between signal
strength and JT4g report).

I described that a little bit broader on wsjt users group here:

https://wsjtx.groups.io/g/main/topic/111843701

But just to reach dev community and ask for fix I think its better here...

So simple exercise (test files for JT4 - Charles G3WDG) and two versions of
wsjt:

for i in *.wav; do echo $i; jt9 -4 -d 3 -b G -f 1000 $i ; done

wsjtx-2.1.0-rc5:
000000_0002.wav
0002  -5 -0.1 1006 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0004.wav
0004  -7 -0.1 1002 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0006.wav
0006  -9 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0008.wav
0008 -11 -0.1 1004 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0010.wav
0010 -13 -0.1  995 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0012.wav
0012 -15 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0014.wav
0014 -17 -0.1 1004 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0016.wav
0016 -20 -0.1  998 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0018.wav
0018 -22 -0.0  995 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0020.wav
0020 -24 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0022.wav
0022 -26 -0.0 1000 $*
<DecodeFinished>   0   1

wsjtx-2.1.0-rc7:
000000_0002.wav
0002 -15 -0.1 1006 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0004.wav
0004 -15 -0.1 1002 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0006.wav
0006 -15 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0008.wav
0008 -15 -0.1 1004 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0010.wav
0010 -14 -0.1  995 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0012.wav
0012 -15 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0014.wav
0014 -15 -0.1 1004 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0016.wav
0016 -16 -0.1  998 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0018.wav
0018 -18 -0.0  995 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0020.wav
0020 -17 -0.1 1000 $* CQ DL0SHF JO54         f
<DecodeFinished>   0   1
000000_0022.wav
0022 -18 -0.0 1000 $*
<DecodeFinished>   0   1


and additionally I guess the commit that was about to fix it - I guess
might be a reason why its not working correctly now:


commit 2044b736dad8444272d3dd5f89cf63716ccbf073
Author: Joe Taylor <joe@...>
Date:   Mon May 20 12:46:36 2019 -0400

    Fix a bug in calculation of S/N in JT4 mode.


Thanks for your help in advance.

-- 
Dawid