I'm trying to expand the functionality of my WS-8478(Falcon) So, I want to disassemble WS-8478 station for hacking a serial port(uart or ttl).
But, I can't find visible screws on the bottom cover!
How to disassemble the station?

or Any picture of bottom of the disassembled station?

My goal is to direclty connect fake-sensor units(PMS5003 air quality, BME280 sensors,...) to station by using ESP8266

, except to connect the serial data stream by RF 915Mhz Tx, Rx module.