: This site often hosts USB-updateable firmware versions for this specific mainboard. You can check the HK.T.RT2938P639 FHD USB page .

contents directly to the root of the USB drive (do not put them in a folder). Insert the USB into the powered-off TV.

: A reliable repository for TV firmware. You can search for the HK.T.RT2938P639 board specifically on the KenotronTV Files Section .