RF Doorbell "Sans-piles" (no batteries required)

Hello
I acquired an RF doorbell “SCS Sentinel” (just the button unit, not the chime) like this

It seems to have a inductive coil inside and the button turns motion into electricity.

Sadly my CC1101 connected to ESP32 running OMG is not picking up a signal at 433.92 Mhz. The manual claims the unit emits 433.92 Mhz at < 10mW.

What strategy to adopt to pick up the RF emitted form this unit ?
Thanks!

Hi, which build of OMG are you using with your CC1101 connected to the ESP32?

Hi DigiH, it is v0.9.9. The versions have come thick and fast recently!

Edit: I saw a technique here https://www.electroschematics.com/433mhz-rf-sniffer/ and info that the " 433.92Mhz" band may actually be wider: 433.05 MHz to 434.79 MHz in the author of that article’s country. I suspect the frequency might be actually different to 433.92Mhz, because I hold my doorbell transmitter right next to the cc1101 and nothing is received. It is also the case for a ESPHOME-based 433.92Mhz receiver I have (this)

I am in France.

yes, maybe a good time to also update to 0.9.11, but what I meant was more the build environment version of OMG

esp32dev-multi_receiver
or
esp32dev-rtl_433
or

I have to say I personally only have experience with the CC1101 transceiver connected to ESP32 for rtl_433 receiving and decoding, which for your device is very likely the wrong setup.a

Alternatively you could also try connecting a SRX882 receiver.

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I have not been BLE to find a pre-built binary to suit my need (which is ESP32 with BLE + RF gateway + Somfy blinds control with CC1101) so I have been building my own from the source. I just now tried esp32dev-multi_receiver to see if I could receive something from this “no battery” doorbell, but I could not, even though I tried all 4 receiving protocols (well, I think I did). Next I will try some kind of sketch to scan different frequencies in the band. Failing that I will buy the chime that goes with this pushbutton unit, and test it. I could maybe look at sensing the sound of the chime instead, although that would be a whole new problem.

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In the end I got a refund, and bought this instead: SIXWGH Wireless Doorbell No Battery required Waterproof Self Powered Door bell Sets Home Outdoor Kinetic Ring Chime Doorbell|Doorbells| - AliExpress I hope this one will be easier to crack.

OK the new no-battery doorbell arrived. OpenMQTTGateway 0.9.9 with CC1101 on 433.92 MHz is not seeing it at least I see nothing on Mosquitto.
Using this scanner program from NorthernMan54 on an arduino Nano with CC1101 : cc1101Scanner/main.ino at master · NorthernMan54/cc1101Scanner · GitHub
I can sense it :
Freq: 433.67
Rssi: -37

Freq: 433.89
Rssi: -21

Freq: 433.90
Rssi: -19

Freq: 433.89
Rssi: -21

Freq: 433.90
Rssi: -19

Freq: 433.78
Rssi: -62

Freq: 433.89
Rssi: -40

Freq: 433.84
Rssi: -54

But how to make OpenMQTTGateway also sense it and send it to Mosquitto?