Only one of three sensors (AlectoV1) are "seen" most of the time

[Guido Jäkel]

Most of the time, just one of three outdoor sensors (temp+hum) at "channel 2" show up decoded data. But there are shown at the hardware station. And also, a bunch of other sensors in the neighborhood  are shown up.

I try to play around with the hardware AGC feature and Gain, also with -Y autolevel without success.

$ ./rtl_433 -M time:iso -C si -M protocol -M level -t digital_agc=1 -M noise -M bits -g 99 -A -R 0 -R 16

[Auto Level] Current noise level -9.7 dB, estimated noise -10.3 dB
Detected OOK package 2025-01-26T18:22:34
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time      : 2025-01-26T18:22:34                    Protocol  : 16
model     : AlectoV1-Temperature                   House Code: 214
Channel   : 2            Battery   : 1             Temperature: 17.40 C      Humidity  : 26 %          Integrity : CHECKSUM
Modulation: ASK          Freq      : 434.0 MHz
RSSI      : -0.1 dB      SNR       : 8.8 dB        Noise     : -8.9 dB
Analyzing pulses...
Total count:  286,  width: 991.47 ms (247867 S)
Pulse width distribution:
 [ 0] count:  286,  width:  492 us [484;512] ( 123 S)
Gap width distribution:
 [ 0] count:    8,  width: 8900 us [8896;8912] (2225 S)
 [ 1] count:  162,  width: 1944 us [1928;1956] ( 486 S)
 [ 2] count:  115,  width: 4028 us [4004;4148] (1007 S)
Pulse period distribution:
 [ 0] count:    8,  width: 9400 us [9396;9404] (2350 S)
 [ 1] count:  162,  width: 2440 us [2436;2448] ( 610 S)
 [ 2] count:  115,  width: 4524 us [4512;4640] (1131 S)
Pulse timing distribution:
 [ 0] count:  286,  width:  492 us [484;512] ( 123 S)
 [ 1] count:    9,  width: 9024 us [8896;10004] (2256 S)
 [ 2] count:  162,  width: 1944 us [1928;1956] ( 486 S)
 [ 3] count:  115,  width: 4028 us [4004;4148] (1007 S)
Level estimates [high, low]:  16089,   2129
RSSI: -0.1 dB SNR: 8.8 dB Noise: -8.9 dB
Frequency offsets [F1, F2]:   19339,      0 (+73.8 kHz, +0.0 kHz)
Guessing modulation: Pulse Position Modulation with fixed pulse width
view at https://triq.org/pdv/#AAB00B040101EC234007980FBC8155+AAB02F040701EC234007980FBC8283838283828383828282828283838382838283828282828283838282838282828283838155+AAB024040101EC234007980FBC828383828382838382828282828383838283828382828282828155
Attempting demodulation... short_width: 1944, long_width: 4028, reset_limit: 8916, sync_width: 0
Use a flex decoder with -X 'n=name,m=OOK_PPM,s=1944,l=4028,g=4152,r=8916'
[pulse_slicer_ppm] Analyzer Device
codes     : {0}0, {36}6b0750643, {36}6b0750643, {36}6b0750643, {36}6b0750643, {36}6b0750643, {36}6b0750643, {36}6b0750643, {25}6b07500

Here some logging of the seldom time it had worked once with the sensors at channel 1, but stopped after that. (This was on a run without any gain options)

time      : 2025-01-26T12:49:35                    Protocol  : 16
model     : AlectoV1-Temperature                   House Code: 110
Channel   : 1            Battery   : 1             Temperature: 9.20 C       Humidity  : 38 %          Integrity : CHECKSUM
Modulation: ASK          Freq      : 433.9 MHz
RSSI      : -10.7 dB     SNR       : 16.4 dB       Noise     : -27.1 dB
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time      : 2025-01-26T12:49:40                    Protocol  : 73
model     : LaCrosse-TX141Bv3                      Sensor ID : 64
Channel   : 1            Battery   : 0             Temperature: 9.20 C       Test?     : No
Modulation: ASK          Freq      : 433.9 MHz
RSSI      : -12.1 dB     SNR       : 14.1 dB       Noise     : -26.2 dB
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time      : 2025-01-26T12:49:40                    Protocol  : 73
model     : LaCrosse-TX141Bv3                      Sensor ID : 64
Channel   : 1            Battery   : 0             Temperature: 9.20 C       Test?     : No
Modulation: ASK          Freq      : 433.9 MHz
RSSI      : -12.1 dB     SNR       : 13.9 dB       Noise     : -26.0 dB
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time      : 2025-01-26T12:49:49                    Protocol  : 16
model     : AlectoV1-Temperature                   House Code: 214
Channel   : 2            Battery   : 1             Temperature: 17.70 C      Humidity  : 24 %          Integrity : CHECKSUM
Modulation: ASK          Freq      : 433.9 MHz
RSSI      : -5.2 dB      SNR       : 19.3 dB       Noise     : -24.4 dB
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time      : 2025-01-26T12:50:06                    Protocol  : 16
model     : AlectoV1-Temperature                   House Code: 110
Channel   : 1            Battery   : 1             Temperature: 9.70 C       Humidity  : 38 %          Integrity : CHECKSUM
Modulation: ASK          Freq      : 433.9 MHz
RSSI      : -10.2 dB     SNR       : 19.6 dB       Noise     : -29.8 dB

Please give me hints, how to investigate what's the reason and receive all three sensors data.

Thank you in advance.

[Christian Z.]

Watch the noise levels. The -20 to -30 dB in the working example is good. Noise above -15 dB would be alarming and the -9 dB is basically a jammed band.

Try some SDR GUI to visualize the band. Maybe it's just some strong but narrow sender, then tune away from that, i.e. try to cover your sender but not the interference with the (default 250k) band.

Otherwise try to locate and shut off that interference.

[Guido Jäkel]

Dear Christian,

the lower noise is just a result of dongle's AGC and rising the software gain to maximum. Up to now, there's no difference to run it with or without.

Also take into account, that the hardware base will recognize the three sensors with it's first transmission and keep this (as long the battery power is good - i have to change batteries once a year). Also placing the "missing" sensors beside the dongle's antenna will not make them show up.

Of course, I don't have any influence of other transmitting devices. But they are sending bursts as usual not more often than every 30secs.

I'll try to connect the dongle to a desktop computer to use an SDR GUI; or maybe try to use rtl_tcp to feed it.

[Christian Z.]

I take it the SDR is some RTL-SDR or better? Noise above -15 dB is atypical. Grab a short recording (e.g. -w file_433.91M_250k.cu8 -T 10) and we can look at the band.

rtl_433 generally needs less that -12 dB noise and at least 9 dB SNR.

[Guido Jäkel]

Dear Christian,

(Sorry, I got no notification about your posting). I just made such an record for 10m, it's not allowed to share it here. Therefore I put it to https://drive.google.com/file/d/1Z7plcnz1WccWIwAJh_7iBtx8IydeLLiF

Sensor "2" is catch six times . At about 1min after start, I notice the flashing LED for a sensor "3", but it don't appear at the console output. An "LaCrosse-TX141Bv3" from neighborhood is sending every 30s.

root@esprimo ~ # rtl_433 -w gjaekel_433.91M_250k.cu8 -T 600
rtl_433 version 24.10 (2024-10-30) inputs file rtl_tcp RTL-SDR with TLS
Detached kernel driver
Found Elonics E4000 tuner
[SDR] Using device 0: Realtek, RTL2838UHIDIR, SN: 00000001, "Terratec T Stick PLUS"
Exact sample rate is: 250000.000414 Hz
Allocating 15 zero-copy buffers

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:30:10

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:30:41

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.60 C      Humidity  : 24 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:33:12

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.50 C      Humidity  : 24 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:13

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.50 C      Humidity  : 23 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:20

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:20

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:44

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.60 C      Humidity  : 24 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:51

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:35:51

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:36:22

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:36:22

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:36:53

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:36:53

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:37:24

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:37:24

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:37:55

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:37:55

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:15

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.50 C      Humidity  : 23 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:26

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:26

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:46

model     : AlectoV1-Temperature                   House Code: 214

Channel   : 2            Battery   : 1             Temperature: 18.60 C      Humidity  : 24 %          Integrity : CHECKSUM

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:57

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:38:57

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:39:28

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:39:28

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:39:59

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

time      : 2025-01-29 07:39:59

model     : LaCrosse-TX141Bv3                      Sensor ID : 64

Channel   : 1            Battery   : 0             Temperature: 8.50 C       Test?     : No
[sdr_callback] Time expired, exiting!
Reattached kernel driver

[Christian Z.]

The recording is good, the band is clear and there are lots of devices.
The AlectoV1, channel 2 ID 214, is at 433.88M and seen at
41.3s
192.3s
313.3s
344.3s
495.3s
526.3s

If we look through the file with https://triq.org/spectrogram-next/ we see the 2nd Alecto at 433.87M sending at around
12s
62s
112s
161s
212s

But the levels are really low. I guess those other senders are stronger and push the AGC down, thus the really low noise levels of -35 to -38 or even -42 dB.

There are detections at low RSSI, like an inFactory-TH at -28 dB at 197 s, but your Alecto seems even harder to detect.
TL;DR the other two Alecto signals are too weak for rtl_433 or the gain too low. A (high) fixed gain might help for the two weak signals, but the first one is really strong and will likely not work then. It might help to tune down a bit, e.g. -f 433.89M

Here is a screenshot of the Alecto ID 214 (clipping at 0 dB), a LaCrosse-TX141Bv3 (at -16 dB) and the inFactory-TH (at -28 dB). The next one shows a very faint 3rd Alecto and the faint 2nd Alecto, I guess. Note the amplitude bars at the bottom:

[Guido Jäkel]

Dear Christian,
thank you for your time and the accurate analysis. Will later try to figure out about gain control and play with it; And also with the frequency as suggested.