Unsupported Doorbell

Hello,

I own a obscure kinetic doorbell, only sold in AU.

No FCC markings, not much info online unfortunately.

Curiosity got the best of me and I purchased a SDR to attempt to capture the signal.

I’m getting spikes @ 433.92mhz

I’ve managed to capture the signal using SDR# (in WAV format):
433.920 MHz Unknown.zip (99.1 KB)

When I attempt a READ raw the signal looks completely different when sent from the flipper, I’m assuming due to modulation?

Not sure how to proceed from here… hoping a subghz guru can assist.

Cheers,

your WAV files are not playing in SDRSharp

Dam, not sure why that is…

I’ve recorded some new ones, hopefully these work.

Audio recording:
Audio.zip (72.2 KB)

Baseband recording:
2022_11_10.zip (4.8 MB)


I do not know. file opens play no

such recording settings?


I’m also using version 1.0.0.1901 of SDR#. not sure if this matters.

Edit: I can replay baseband recordings:

put earned. and that the transmission from the key fob is so short when you hold the button? and very similar to AM frequency 433.92 record 5+ button presses on the flipper and keep the button pressed for 3+ seconds

The transmission is from a kinetic doorbell:

bd146bc6ddf12489a2a365e797817b5c7c13d4dd

No battery required in button, the movement of the button generates enough energy to send transmission.

Edit: Not sure if this helps, but this is a recording of transmission spam.

21-11-09_433900000Hz.zip (7.0 MB)
21-11-20_433900000Hz.zip (5.6 MB)
21-11-30_433900000Hz.zip (4.7 MB)

Edit 2: Is it possible to decode the sdr# capture and manually create a .raw to imitate the transmission?

Edit 3: The transmission being sent from the flipper looks very different:

write a raw record with a flipper. AM 650 433.92 that it does not look right does not mean that it is not transmitting correctly

Transmitting from flipper does not work, I have tested AM650 & AM270.

Sending one or multiple… no success.

give me a few consecutive recorded buttons. perhaps the protocol is dynamic, and therefore does not accept

Post 7 has a recording with consecutive button presses.

Please note every two transmissions is one button press in that recording, as the button generates transmission on press & depress.

The bell only requires the first transmission to chime… I can hold the button down and the bell will chime.

uint_2048_t from on the flipper discord was kind enough to assist with manually create the .sub for me.

I’m going to drive my neighbours crazy with all the chiming for a little while!

doorbell.sub (723 Bytes)

hello, what was the solution ???, I have the same problem

Edited by moderator.

Please, what is the actual solution? the file doesn’t work for mine.

I have the same problem. I suspects the doorbell is of the same type with the kinetic force (https://www.pearl.de/pdocs/NX7872_11_169883.pdf). Able to capture signal on 433.92 but on playback it doesn’t ring the bell

So I went and dug into the discord chat conversation and think I found the part where they fixed it. Basicly it’s cleaning up the file, for search engine purposes I’ll post it here:

Applications application is runy 10-11-2022 21:28

it’s still a mess if you zoom enough, but since i get more smaples, i can capture more mess and it looks more blocky

Afbeelding

you’re really going to need to play with the timings in the .sub file

basically… the “55 -145” part means a zero bit, and a “155 -45” is a one

perhaps try “50 -150” instead of “55 -145”; and “150 -50” instead of “155 -45”. try measuring the timings on the original file too

you can just edit the first long “Raw_Data” line correctly, and then copy it twice, the signal is identical 3 times

  • ruckus 10-11-2022 21:34

it fucking worked!!

  • holy shit

youre a genius

  • THANK YOU!

  • Applications application is runy 10-11-2022 21:35

haha

  • awesome

ruckus 10-11-2022 21:35

what the hell…

Applications application is runy 10-11-2022 21:35

well, next time you run into a signal, you know what to do

  • you did most of the work anyway, since you actually went out, bought a sdr and learnt to play with it

ruckus 10-11-2022 21:36

i really need to learn to break things down like you did, that is so cool

can you recommend any material?

Applications application is runy 10-11-2022 21:36

80% of the signals out there are like this, fm, infrared, etc

  • you have a carrier, or you don’t

ruckus 10-11-2022 21:37

i’ve owned the sdr for less than 24 hours wrong channel

Applications application is runy 10-11-2022 21:37

it’s really more of a practice thing, to be fair, but maybe take make the flipper play some simple signals, and see if you can figure them out?

(since you already have a SDR to record them, and a flipper with a ton of signals on it)

ruckus 10-11-2022 21:37

im blown away

so cool

Applications application is runy 10-11-2022 21:38

if you want to dive significantly deeper, the hackrf/gnu radio tutorials are neat