Juma 100d clone wireless rs232 mod

[Ronald PC3Y]

I have an RS928 /Juma 100d clone and already upgraded the firmware from 1.05Q to the latest version with the posibility for the serial control/rs232. 

I want to interface the controller directly with an ESP32 with webinterface or serialport over tcpip and have been studying the schematics of the control bord. From the pic controller there are 2 x 2 lines that go to the RS232 converter (IC10). I suspect that pin 11 and 12 are the RX/TX ttl signals that are being converted to rs232 for the output. The ESP32 uses 3.3v logic and the pic 5v. 

I am not completly sure how to interface this.

Do i need to use an FT232RL to connect the ESP32 or an logic level converter?

Anyone have tried this before? 

Any help or ideas would be helpfull.

schematics

Thanks

Ronald