I noticed the bit at the end about V6 and  the occasional dropped character and that this was not a serial line issue. I have the same issue in my V6 port to the TI-990 and always assumed that it was a bug I introduced myself when hacking the tty driver.

Does anyone remember, was this a real life bug back in 6th edition back in the 1970’s? Maybe only showing at higher baud rates?

Paul