Hacking hardware - making a doorbell (noise) detector - killed my nodecmu?

So i wanted to automate that when my (dumb old) doorbell rings, my hue lights flash and my ip-camera takes a picture and sends it to my phone.

I found an old piece of hardware, originally used to make a t-shirt blink to the beat of the music.
(see picture)

(click it to see all info)

It works on 2x 1,5v AAA batteries. I used a nodemcu to detect change in volts (when the mic detect a sound, it makes some leds burn.) My first try was using the 3,3v output from the Nodemcu and provide power to the device. then I hooked up 2 leds to the output of the device. I connected the A0 analog input of the nodemcu to detect the change in voltage.
This all worked for a few minutes. then I lost wifi connection to the Nodemcu.
I though maybe the 3,3v is too much for the little device, so I added the battery connection again. only hooked the ground to the - of the led output and the A0 to the + output…
The mic and leds worked fine, and It detected changes between voltage (from 0 to 1 volt) on my A0 analog input.

now my nodemcu seems broken. I’m losing connection to the wifi, even without hooking it up to something, it drops wifi connection every X seconds and sometimes it stays offline untill I upload some code again. I’m affraid to hook up a new nodemcu because I might kill it as well.
My question, am I missing something? should I protect my nodemcu from 1 volt input? should I connect my ground to something else than the led negative?

second question, in my code (simple analog to digital detection) to detect volt changes, I added refresh: 1s. is there another way to do constant detection of volt changes?

thanks for all your help. this forum has learned me so much about automation, arduino’s ,… A new world opened up to me thanks to you guys and girls!

I think you should post this on some hardware forum and not here.

With what did you flash your nodemcu ? If you attach it to a pc, can you still flash it again ?

I flash it with esphome. It works every time I flash it but then after a while it stops working.
Indeed, this is more of an Arduino thing than a home assistant… Sorry

OK, check the forum about esphome WiFi losing connection. Plenty of messages.

Do you have any other ESP devices online? They all need to have a unique connect ID else one of them will get kicked offline.

Can I also say that this seems a complicated way of telling if your doorbell has been pressed. What is wrong with measuring the voltage over the doorbell?

May seem like a crazy question but do you have any Roku devices?

I had an issue with esp8266 devices dropping significant packets. Probably in the 95% range. When I switched them to a wifi AP in a different room, they dropped much less packets. I then started having problems with my laptop dropping packets but not nearly as much. My Ring doorbell was also having issues. I finally tracked it down to the Roku 3 in my master bedroom. It’s directly on the other side of the wall from my WiFi router. What had happened was I had changed my SSID months prior to something new and decided to discontinue the old SSID. What I didn’t realize was my Roku 3, even though it was configured to use ethernet, was previously on the old SSID. It was still searching for that old SSID and would increase its broadcast strength and basically drowned out all other WiFi devices on the 2.4GHz frequency. It would do this over and over and over again. The solution was to join it to the new SSID then switch back to ethernet. There’s also a hidden menu you can use to turn off that “feature” on the roku.

It could also be any other device on your network that’s doing something similar.

Use a WiFi sniffer on your smartphone and look for something broadcasting in increasing strength over a small period of time. If you see such a thing, that’s your problem.

Once I fixed the Roku WiFi issue, I have had 0 issues.

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A few other suggestions.

You can use is a zwave motion sensor. When motion is detected, dump a pic or series of pics and e-mail or display the video on a device. I’m using smartthings integrated with Home Assistant for this along with a smartthings motion sensor. I have a webhook configured on a linux server that’s triggered by smartthings when the zwave motion sensor detects motion. It’s so sensitive that squirrels set it off but not too sensitive that it’s an annoyance.

Instead of using that device, use a 24vac relay connected directly to the nodemcu. You won’t sending any voltage to the nodemcu, only closing a circuit between two pins.

I have a ring doorbell. In addition to the notification and video from the app, I also detect motion using the binary sensor. With that, I trigger a webhook that grabs 3 pictures and e-mails them to me. Again triggered by smartthings but can also be triggered by home assistant directly.

Previously, I had done all this using MQTT but with the direct smartthings integration, I use that now. However, you can still use MQTT if you are familiar with it.

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