This ESPHome based doorbell is a modified Wemos Relay Shield for D1 Mini with an integrated buck converter to power the Wemos without the need of an external power source.
The doorbell has 3 connectors to make a “dumb” classic doorbell smart:
- Power in: here goes the power from the doorbell transformator (AC/DC 40 volts max)
- Doorbell: here goes the doorbell
- Switch: here goes the push button placed at the door
For a case, please look here: https://www.prusaprinters.org/prints/75277-zuidwijk-esp-doorbell-case