On 22/06/2021 08:16, Matt Burke via cctalk wrote:
The VT640 had a green phosphor. This was a 3rd party upgrade for the
VT100 from Digital Engineering which gives the VT100 graphical
capabilities. Part of the upgrade involved changing the picture tube. I
suspect this was to reduce flicker as the phosphor has a high persistence.
Here is an original advert for the upgrade:
https://books.google.co.uk/books?id=rO0QAcSJpQUC&pg=PA27
Matt
The ones I used had a VT640 (although the only used for the graphics
side that I remember was a labyrinth game and some ALGOL code I wrote to
plot some coursework). I would never have guessed that the tube got
changed as part of the process, but it looks like you probably bought
the modified VT100 from Digital Engineering rather than installing a kit
yourself.
Antonio
--
Antonio Carlini
anto...@acarlini.com
