i got hold of 9 pieces TTL to RS232 converters based on LT1381 chip and lm78L05A voltage regulator SAF
the datasheet for the chip says
The LT?1381 is a dual RS232 driver/receiver pair with
integral charge pump to generate RS232 voltage levels
from a single 5V supply....
so seen from TV side it should work very well as it is bidirectional
i havent had time to test them with my C6500 yet or to figure out which pin should be connected where..
members of SamyGO Project donors Group pay only the shipping costs (developers only half of the shipping), all other 8? plus shipping

You do not have the required permissions to view the files attached to this post.
//UE40C6500 @ T-VALDEUC 3011 // rooted manual HotelMode style // PVR to NFS via 18MB on-the-fly sparse XFS // >> decommissioned due to tuner death
//UE46F8090 @ T-FXPDEUC 1136 // rooted by new Widget // root starting with empty usb drive
FYI: you can close your ssh session with SamyGO with
If you can't fix it using dvct tape, you are not using enough dvct tape.