Sorry for writing in english and not french, my mother language is Catalan and I feel more comfortable in english than in french. Answers in french are very welcome!
I’m a retrocomputing enthusiast, and I always wanted a Dumb Terminal. I’ve found several Videotext terminals in our local buy/sell app and found several Minitels and spanish Telesincro.
The fact is that there is a Telesincro Bull terminal that is very nice, appears to be brand new, but it does not bring external serial port and there is no information on the internet. So, considering that this device is a brother of french Minitels: Do you think that a serial port can be « extracted » in some way?
There are also Minitels without external DIN serial: In that cases, they can be also hacked? If they have modem, they must have an UART… so the Telesincro case should be the same: Getting the serial port « before » it gets into the Modem. Maybe what I’m saying is nonsense…
I posted this Mastodon thread (you will see the pics): Andreu RetroCGA: "I always wanted a Dumb Terminal... Now I'm tempte…" - RetroChat