MQTT Doorbell

Can you tell me which hardware parts you used and send me links to bye them? Thanks :slight_smile:

Would love to see a clip of it in action :slight_smile:

Not a really exciting clip, but here it is :slight_smile:


I used:

*Arduino Wemos d1 Mini Pro: (

Good luck!

@armandjanssen I like your setup. I’m new with Wemos D1 Mini and maybe you can show which pins to connect and how to upload the arduino code.

I would appreciate if you can make a tutorial vid how to set up step by step from start to end. .

There are enough resources online which describe this.

Then play around and try and find more video’s and tutorials. :slight_smile:

Here’s video of mine

There’s much more info in the doobly-doo of the video


Great! I like the way you have Google Home integrated with the doorbell.

I can also ring the door remotely. Not sure why I’d wanna do that, but I can

@quadmasta U could use that functionality to use the bell as an alarm signal.
In my solution, the bell would subscribe to an mqtt topic and then enter a loop which rings te bell each second for 2 minutes (or something like that).

It’s an electro-mechanical relay so the relay would probably die. If you used a SSR, definitely

@quadmasta Do you mean a relay like this? If yes, please elaborate why it would / could die?!
I don’t know that much about this stuff. Just copying, stealing and learning on the way. :slight_smile:

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They don’t deal well with fast, repeated switching. The coil overheats and they either stick open or closed. A solid state relay is essentially a giant transistor. Here’s a 5V Breakout with a SSR on it. Looks like it’s normally open so it’d work perfectly for this project.

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Little update.

I had some issues with interference from cables that run along the doorbell cables in the wall. Whenever someone turned on the light in the downstairs bathroom it caused the Wemos to trigger and the doorbell to go off.
I suspect that the wires are close to one and another causing some electric field which in turn was detected by the Wemos as if the doorbell was pressed. Getting the wiring redone was not an option so I had to check for different ways.

Inspired by the following blog I order a reed relais. Basically this relais makes contact when a magnet is present. The bell operates with a magnetic field. So when the old doorbell is activated it creates the magnetic field and the reed relais makes contact and then all the magic happens :slight_smile:

The test with a magnet was working and sofar it seems to work when it is all in place as well.

My layout is something like this. Although I need to tidy things up like, but I wait with this until it all proofs to be reliable.

I used:


Nice! A very non-intrusive way to picking up state change :slight_smile:

I tried something similar. I used a Vision Z-wave door sensor. But the bell solenoid did not make a strong enough magnetic field to trigger it. A small “Arduino” reed switch might work better.

Looking at your layout I was wondering where the wemos D1 gets the power from? In the picture the wemos D1 is only connected by the reed switch. Is that correct?

Edit: I got it all working by powering the Wemos D1 via usb and play sound with Chromecast Audio when doorbell rings. Sweet! However I want the Chromecast to pause when doorbell rings and continue to play after that. Any tips how to automate this?

Sorry, indeed I missed where the wemos gets it’s power from. It is powered by USB.

I don’t have any ideas how to resume. But if you figure that out I would very much appreciate it when you could share that solution :grin:

I run mine off of an AC/DC adjustable buck controller. Voltage from the doorbell transformer(18VAC) goes into it and 5VDC comes out

@quadmasta what would you have used if you would have to step down from 230v to 3.3v?

To which pins did you connect, simple 5v and gnd??

This is what I used. It can adjust 2.7-27V AC or DC to 1.5-7VDC. I’d be really shocked if your doorbell ran on mains power and didn’t have a transformer.