[solved]Re: wip/wsjtx does not decode FT8 radio signals.

[Ramiro Aceves <ea1abz%gmail.com@localhost>]

El 6/1/26 a las 18:10, Michael van Elst escribió:
> ea1abz%gmail.com@localhost (Ramiro Aceves) writes:
>
> > I will continue investigating. Now the sample rate seems to be ok but
> > there will be a reason for no decodes. Perhaps the card samples at 44100
> > Hz but NetBSD resamples it to 48000 and "destroys" it in some way?
> > It does not occur with the internal card because perhaps it works fine
> > at 480000 and no resamping is needed?
>
>
> The settings of /dev/audioN (or /dev/soundN) are those of a "virtual"
> device.
>
> The output of 'audiocfg list' shows the possible settings of the
> hardware instead. The data is converted on the fly from and to
> the "virtual" settings.
>
> With 'audioconfig set' you can change the hardware settings
> (within the limits of what the hardware driver supports).
>
> If hardware and "virtual" device have the same settings, there
> is no conversion done.
>
> N.B. when resampling takes place, the conversion has a rather
> low quality, in particular when the signal hasn't passed a
> reasonable filter. But I don't know how much that affects
> your decoder.

Thanks Michael for your great explanation!

I have it working now this way, configuring the card for recording at a 
sample rate of 44100 Hz using audiocfg:



netbsd-nuc# audiocfg list 1
1: [*] audio3 @ uaudio1: USB audio
       playback: 2ch, 44100Hz
       record:   2ch, 48000Hz
       (P-) slinear_le 16/16, 2ch, { 44100 }
       (P-) slinear_le 16/16, 2ch, { 44100 }
       (-R) slinear_le 16/16, 2ch, 8000-48000Hz

netbsd-nuc# audiocfg set 1 r slinear_le 16 2 44100
setting audio3 to slinear_le:16, 2ch, 44100Hz

netbsd-nuc# audiocfg list 1
1: [*] audio3 @ uaudio1: USB audio
       playback: 2ch, 44100Hz
       record:   2ch, 44100Hz
       (P-) slinear_le 16/16, 2ch, { 44100 }
       (P-) slinear_le 16/16, 2ch, { 44100 }
       (-R) slinear_le 16/16, 2ch, 8000-48000Hz
netbsd-nuc#

Now it decodes amateur radio FT8 signals perfectly:


0014 WSJT-X
212415  -3  1.1 1178 ~  LU3DW II2WWA RR73
212415   2  0.8  340 ~  HC5CG IK4LZH JN54
212415 -13  0.2 1506 ~  II7WWA F4JYC 73
212415 -12  0.7 2353 ~  KV8S IQ4JO JN63
212415 -13  0.8  852 ~  <...> PY1KV/QRP
212415 -19  0.8  914 ~  KO4MEX F4LQD JN07
212415 -17 -0.8 2353 ~  W4I IU5KZG JN53
212415 -15  0.8 1564 ~  K6RO 9A6R R-04
212430  -5  0.4  853 ~  <PY1KV/QRP> DL8GAP -12
212430  -2  0.7 2140 ~  EA1ZT RR73; IU5VKD <...> -18
212430   1  0.7 1962 ~  CQ EA8DHQ IL18
212430   0  0.7 1365 ~  KC2ZZR 9A9A +02
212430 -16  2.1 1645 ~  9A6R DJ7YP JO42
212430 -14  1.7 1503 ~  IU8ODA F5OYA/P JN13
212430 -10  2.0 1458 ~  II2WWA LU3DW 73
212430 -16  0.8  722 ~  PY4STO DH1JG JO31
212430 -12  0.7  502 ~  II2WWA PD0R R-19
212430 -18  0.7 2069 ~  9A6R K6RO -17
212430 -17  0.8 1555 ~  IU8ODA NP4TX -08
212430 -22  0.7  930 ~  CE2SV ON8EM JO10
212430  -3  0.7 1934 ~  F4JYC F5RRS JN36
212430 -15  0.3 1996 ~  CQ OR7K JO21
212430 -10  0.6 1382 ~  CQ NA PD8DX JO32
212445   3  0.7  340 ~  HC5CG IK4LZH R-05
212445 -15  0.6  914 ~  KO4MEX F4LQD JN07
212445 -13  0.6  853 ~  DL8GAP <PY1KV/QRP> R-08
212445  -6  0.9 1178 ~  PD0R II2WWA RR73
212445 -14  0.7 1114 ~  CQ V31DL EK57
212445 -12  0.1 1506 ~  F5RRS F4JYC -04
212445 -17  0.8 2098 ~  9A9A LU2VPG -24
212445 -17  0.6 1565 ~  K6RO 9A6R RR73
212445 -15  0.6 1164 ~  CQ PY2AMP GG66
212500   0  0.9 2140 ~  IU5VKD ZW5B RR73
212500  -5  0.3  853 ~  <PY1KV/QRP> DL8GAP RR73
212500  -5  0.5 1934 ~  F4JYC F5RRS R-10
212500   0  0.6 1248 ~  CE2SV DL5AA +12
212500 -11  0.2 1996 ~  CQ OR7K JO21
212500 -10  0.6  502 ~  II2WWA PD0R R-19
212500  -9  0.6 2352 ~  N3WXW IQ4JO JN63
212500  -4  0.5 1365 ~  KC2ZZR 9A9A RR73
212500  -7  0.6 1415 ~  II2WWA PY1AX GG87
212500 -13  1.5 1503 ~  IU8ODA F5OYA/P JN13
212500 -16  0.6 2069 ~  9A6R K6RO 73
212500 -20  0.6  722 ~  PY4STO DH1JG JO31
212500 -17  0.6 1555 ~  VE4BDR NP4TX -18
212500 -16  1.5 1645 ~  9A6R DJ7YP JO42
212500 -10  0.5 1383 ~  CQ NA PD8DX JO32
212500 -20  0.7 2063 ~  CE2SV G6PWS IO91
212500 -23  0.6  930 ~  CE2SV ON8EM JO10
212515  -3  0.8 1178 ~  PY1AX II2WWA -05
212515 -11  0.5  853 ~  <DL8GAP> PY1KV/QRP 73
212515  -4  0.4  286 ~  KA1BJX ON6JL RR73
212515 -15  0.5  913 ~  KO4MEX F4LQD JN07
212515 -14  0.5 1651 ~  KO4MEX IW3BYL JN56
212515 -11 -0.1 1505 ~  F5RRS F4JYC RR73
212515 -12  0.6 1114 ~  N8ADK V31DL -09
212515  -9  0.6  341 ~  HC5CG IK4LZH 73
212515 -18  0.5 1756 ~  YN1Y DG1CMZ JO60
212515 -14  0.7 1162 ~  CQ PY2AMP GG66
212515 -19  0.6 2099 ~  9A9A LU2VPG -24
212530   0  1.8 2141 ~  VA3BRC ZW5B -13
212530  -1  0.4 1248 ~  CE2SV DL5AA RR73
212530  -7  0.1  853 ~  <PY1KV/QRP> DL8GAP 73
212530 -13  1.3 1503 ~  IU8ODA F5OYA/P JN13
212530 -13  0.4  502 ~  II2WWA PD0R R-19
212530   0  0.4 1962 ~  CQ EA8DHQ IL18
212530 -17  0.3  681 ~  CE2SV IZ1DRY JN35
212530  -5  0.4 1365 ~  LU2VPG 9A9A R-08
212530 -18  0.4  722 ~  PY4STO DH1JG JO31
212530 -19  0.4 2070 ~  CQ K6RO FN43
212530   0  0.3 1935 ~  F4JYC F5RRS 73
212530 -13 -0.1 1996 ~  CQ OR7K JO21
212530  -6  0.4 1415 ~  II2WWA PY1AX R-10
212530  -7  0.2 1383 ~  CQ NA PD8DX JO32


Now a 440 Hz audio signal injected from the signal generator prints on 
the waterfall a solid and narrow vertical line as it corresponds to a 
sine wave, and it is placed exactly at 440 Hz.

Thanks so much.

Regards.
Ramiro.


>