Making progress on the only known Positron 9000 to exist https://binarydinosaurs.co.uk/Museum/Positron/index.php

It's the first time I've seen a SAA5050 being used to generate 80 columns.

[Linked Image from i.imgur.com]

BBC Model B, ATPL Sidewise, Acorn Speech, 2xWatford Floppy Drives, AMX Mouse, Viglen case, etc.