Bitron Doorbell in Home Assistant.
The intercom is powered by a 17V audio signal, which is generated with the help of a tone generator in the door speaker.
A level converter is needed to isolate the 17V from the 3.3V GPIO.
The Circuit is under the Wemos Board.
Please use not Linear Voltage Regulator, it consumes too much energy and is inefficient, I later used a Buck Converter.
- Tap voice connection
- Recorded voice messages