LaCrosse TX141-Bv3 signal not receiving by rtl

David Innes

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Feb 28, 2021, 12:40:48 AM2/28/21

to rtl_433

Kubuntu 18.04 32 bit with NESDR Mini 2+ R820T2 SDR & DVB-T dongle

LaCrosse TX141-Bv3 temperature sensor

Running:

$ rtl_fm -f 92.5e6 -M wbfm -s 200000 -r 48000 - | aplay -r 48000 -f S16_LE

picks up local FM radio station fine

Running:

$ gqrx tuned to 433.92 MHz

picks up the temperature sensor signal every 30 sec.

However, running:

$ rtl_433 -R 73

rtl_433 version 20.11 (2020-11-13) inputs file rtl_tcp RTL-SDR

Use -h for usage help and see https://triq.org/ for documentation.

Trying conf file at "rtl_433.conf"...

Trying conf file at "/home/david/.config/rtl_433/rtl_433.conf"...

Trying conf file at "/usr/local/etc/rtl_433/rtl_433.conf"...

Trying conf file at "/etc/rtl_433/rtl_433.conf"...

Registered 1 out of 179 device decoding protocols [ 73 ]

Detached kernel driver

Found Rafael Micro R820T tuner

Exact sample rate is: 250000.000414 Hz

[R82XX] PLL not locked!

Sample rate set to 250000 S/s.

Tuner gain set to Auto.

Tuned to 433.920MHz.

Allocating 15 zero-copy buffers

rtl_433 hangs with no output data from the TX141-Bv3 sensor. Adjusting the frequency to 434.05 MHz based on the gqrx analysis doesn't make a difference.

Any suggestions for a fix would be appreciated.

Thanks,

David

Christian Z.

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Feb 28, 2021, 2:37:08 AM2/28/21

to rtl_433

Also try `-vvv` or `-A` to see if there is data.

David Innes

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Feb 28, 2021, 1:37:49 PM2/28/21

to rtl_433

Using -vvv and -A shows data being received coincident with the pulse from the temp. sensor:

$ rtl_433 -R 73 -vvv

gives two groups of 148 pulses:

Pulse data: 148 pulses

[ 0] Pulse: 244, Gap: 243, Period: 487

[ 1] Pulse: 244, Gap: 245, Period: 489

[ 2] Pulse: 244, Gap: 244, Period: 488

[ 3] Pulse: 244, Gap: 243, Period: 487

[ 4] Pulse: 62, Gap: 124, Period: 186

[ 5] Pulse: 60, Gap: 123, Period: 183

[ 6] Pulse: 121, Gap: 63, Period: 184

[ 7] Pulse: 59, Gap: 123, Period: 182

[ 8] Pulse: 120, Gap: 63, Period: 183

[ 9] Pulse: 61, Gap: 122, Period: 183

[ 10] Pulse: 121, Gap: 62, Period: 183

[ 11] Pulse: 122, Gap: 62, Period: 184

[ 12] Pulse: 120, Gap: 62, Period: 182

[ 13] Pulse: 62, Gap: 122, Period: 184

etc.

$rtl_433 -R 73 -A

Detected OOK package 2021-02-28 10:17:14

Analyzing pulses...

Total count: 148, width: 127.54 ms (31884 S)

Pulse width distribution:

[ 0] count: 16, width: 972 us [964;980] ( 243 S)

[ 1] count: 68, width: 240 us [232;248] ( 60 S)

[ 2] count: 64, width: 484 us [480;492] ( 121 S)

Gap width distribution:

[ 0] count: 16, width: 972 us [972;980] ( 243 S)

[ 1] count: 67, width: 492 us [484;532] ( 123 S)

[ 2] count: 64, width: 244 us [240;252] ( 61 S)

Pulse period distribution:

[ 0] count: 16, width: 1948 us [1940;1956] ( 487 S)

[ 1] count: 131, width: 732 us [720;772] ( 183 S)

Pulse timing distribution:

[ 0] count: 32, width: 972 us [964;980] ( 243 S)

[ 1] count: 132, width: 244 us [232;252] ( 61 S)

[ 2] count: 131, width: 488 us [480;532] ( 122 S)

[ 3] count: 1, width: 10004 us [10004;10004] (2501 S)

Level estimates [high, low]: 4252, 175

RSSI: -5.9 dB SNR: 13.9 dB Noise: -19.7 dB

Frequency offsets [F1, F2]: 3896, 0 (+14.9 kHz, +0.0 kHz)

Guessing modulation: Pulse Width Modulation with sync/delimiter

view at

https://triq.org/pdv/#AAB00B040403CC00F401E827148055+AAB02C040103CC00F401E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F401E827148055+AAB02C040103CC00F401E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F401E827148055+AAB02C040103CC00F401E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F401E827148055+AAB02B040103CC00F401E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A19355

Attempting demodulation... short_width: 240, long_width: 484,

reset_limit: 984, sync_width: 972

Use a flex decoder with -X

'n=name,m=OOK_PWM,s=240,l=484,r=984,g=0,t=0,y=972'

pulse_demod_pwm(): Analyzer Device

bitbuffer:: Number of rows: 4

[00] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[01] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[02] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[03] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

Detected OOK package 2021-02-28 10:17:14

Analyzing pulses...

Total count: 148, width: 127.52 ms (31881 S)

Pulse width distribution:

[ 0] count: 16, width: 972 us [960;980] ( 243 S)

[ 1] count: 68, width: 240 us [236;248] ( 60 S)

[ 2] count: 64, width: 484 us [480;492] ( 121 S)

Gap width distribution:

[ 0] count: 16, width: 972 us [972;980] ( 243 S)

[ 1] count: 67, width: 492 us [484;536] ( 123 S)

[ 2] count: 64, width: 244 us [244;252] ( 61 S)

Pulse period distribution:

[ 0] count: 16, width: 1948 us [1936;1960] ( 487 S)

[ 1] count: 131, width: 732 us [728;776] ( 183 S)

Pulse timing distribution:

[ 0] count: 32, width: 972 us [960;980] ( 243 S)

[ 1] count: 132, width: 240 us [236;252] ( 60 S)

[ 2] count: 131, width: 488 us [480;536] ( 122 S)

[ 3] count: 1, width: 10004 us [10004;10004] (2501 S)

Level estimates [high, low]: 4304, 203

RSSI: -5.8 dB SNR: 13.3 dB Noise: -19.1 dB

Frequency offsets [F1, F2]: 3977, 0 (+15.2 kHz, +0.0 kHz)

Guessing modulation: Pulse Width Modulation with sync/delimiter

view at

https://triq.org/pdv/#AAB00B040403CC00F001E827148055+AAB02C040103CC00F001E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F001E827148055+AAB02C040103CC00F001E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F001E827148055+AAB02C040103CC00F001E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A1928055+AAB00B040303CC00F001E827148055+AAB02B040103CC00F001E827149292A192A192A1A1A19292A19292A1929292A1A192A1A1A192A19292A192A1A19355

Attempting demodulation... short_width: 240, long_width: 484,

reset_limit: 984, sync_width: 972

Use a flex decoder with -X

'n=name,m=OOK_PWM,s=240,l=484,r=984,g=0,t=0,y=972'

pulse_demod_pwm(): Analyzer Device

bitbuffer:: Number of rows: 4

[00] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[01] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[02] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

[03] {33} d4 6d c8 b4 80 : 11010100 01101101 11001000 10110100 1

etc.

Christian Z.

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Feb 28, 2021, 2:25:24 PM2/28/21

to rtl_433

Do you consistently see only 4 repeats/rows? The sensors is supposed to send 12 and the decoder requires a minimum of 5 rows (of 32+ bits).

Christian Z.

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Feb 28, 2021, 11:59:58 PM2/28/21

to rtl_433

Can you look into the sample data, or upload a sample (from -S unknown) to check? What are the labelings on the device?

Christian Z.

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Mar 1, 2021, 1:09:43 AM3/1/21

to rtl_433

That's really just two clean transmissions of 4 repeats. This must, again, be a different hardware revision. We'll shortly add this.

David Innes

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Mar 6, 2021, 4:36:07 PM3/6/21

to rtl_433

Now works with the change to include LaCrosse TX141-Bv3 with only 4 repeats.

Christian Z.

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Mar 6, 2021, 4:59:01 PM3/6/21

to rtl_433

Thanks for the feedback. If you ever find a revision marking or something to distinguish this "low-energy" ;) version let me know for the docs.

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LaCrosse TX141-Bv3 signal not receiving by rtl_433

David Innes

Christian Z.

David Innes

Christian Z.

Christian Z.

Christian Z.

David Innes

Christian Z.