In essence, you connect a common 433 MHz receiver module to an ESP32 ... it toggle a relay hooked up to a loud siren. Even if you aren’t looking to make your own makeshift alarm system, the ...

To simplify this, [Timm Bogner] created Farm Data Relay System which simplifies the process ... The FDRS uses a combination of ESP32/8266 sensor nodes for short range, and LoRa nodes for long ...