guide · smart home

Cheap wireless doorbells transmit a simple code on 433 MHz. An ESP32 with a receiver picks it up and the doorbell press reaches Home Assistant – for example as a notification on the phone.

The components and pins below are a typical choice; specific modules may differ.

Components

ESP32-C3;
a superheterodyne 433 MHz receiver, the RX470C – more sensitive and stable than the cheap XY-MK-5V, and it ships with an antenna;
antenna: included with the RX470C; for longer range you can instead use a wire about 17.3 cm long (a quarter wavelength for 433.92 MHz).

Wiring

receiver ESP32-C3

VCC 3V3

GND GND

DATA GPIO4

1. Capturing the code

The doorbell code can be found with a sketch in the Arduino framework using the rc-switch library (the ReceiveDemo_Advanced example), which prints the code, length and protocol. ESPHome with dump: rc_switch works just as well.

2. ESPHome configuration

remote_receiver:
  pin: GPIO4
  dump: rc_switch
  tolerance: 50%
  filter: 250us
  idle: 4ms
  buffer_size: 2kb

binary_sensor:
  - platform: remote_receiver
    name: 'Doorbell'
    rc_switch_raw:
      code: '100010000000000010111110' # example - code from your own capture
      protocol: 1
    filters:
      - delayed_off: 1s

The doorbell sends its code repeatedly and only briefly; delayed_off turns that into one clean press.

3. Home Assistant

The “Doorbell” binary sensor appears through the ESPHome integration. An automation triggered when it turns on can send a phone notification, switch on a light or log the event.

Things to watch out for

The 433 MHz band is busy; filter and tolerance help against false presses.
Place the receiver away from sources of interference (power supplies, the Wi-Fi router).

A dumb wireless doorbell in Home Assistant via RF433 and ESP32