I finally managed to free some time from work and replaced the old setup for the new setup… and that didn’t work well. Confused as I was, I tried to figure out what exactly is happening. My own bell is not a classic ring-bell, but a more fancy “ding-dong” bell (is there even a name for it?). And I figured out why/what’s failing…
Why did the test setup works flawless and my own doorbell not? Well, if I had tested it more, it would have saved me about 50 euro on now useless custom buck converters 🤭
It seems that a classic ring-bell doesn’t draws a lot of current, and the ding-dong bell does. Therefor it causes the Wemos to brown-out. I failed to check the power rail on my pcb. An extra capacitor did the trick and now it is working perfect with my dingdong-bell.
So back to the drawing board and redesign the pcb it is:
After making the PCB slightly wider and a little larger, I was able to squeeze in an extra capacitor to stabilize the power rail. I’m confident that this works and did another order at jclpcb.
Probably the new version will arrive within 2~3 weeks and will be in my webshop soon after 🙂