Keep the TV powered for at least 1–2 minutes. Do not turn off the power!
Finding the right firmware requires knowing your panel's resolution. Firmware files are typically named with resolution and panel brand (e.g., TP.RD8503.PB816_1920x1080_Samsung.bin ). Common Sources tp.rd8503.pb816 software
Place the firmware file (usually named RDA8503.bin or similar) into the root directory (do not put it in a folder). Power Off: Unplug the TV from the power outlet. Insert USB: Plug the drive into the TV's USB port. Keep the TV powered for at least 1–2 minutes