I’m trying to find out as much information about the Tangerine 1648 VDU card, with a view to making a replica. Is there anyone out there who still has one? It’s a bit of an odd thing, as it’s a VDU that displays 16 lines of 48 characters and it’s attachment to a computer is serial RS232, or current loop, or parallel data.
There’s detailed discussion of the data gathering at (are we allowed to link to other fora?):
https://www.vintage-radio.net/forum/showthread.php?t=228097
At the moment I am trying to work out the circuit from a cover photo on a magazine and some other inferences. Obviously, if someone has one of these then, if access to it can be arranged, then that would be a more straightforward way to do this. The documentation that went with the 1648 had a circuit diagram in it, so if just the documentation exists, then that would also be useful.