Now the PiDP-8 basically works, I decided that it needs a paper tape reader for company. A friend gave me some PDP-8 tapes to test with, so yesterday was spent cobbling together a prototype.

Work was made easy because NeXT, at the Vintage Computer Forum blogs, shows how a grid of photodiodes on normal perfboard is enough to make the scanner part. So I copied that element, but decided to forego the other electronic bits and just use the analog pins from an Arduino Mini Pro to do everything straight from the photodiode outputs.

It seems to work, but it'll need a lot of testing to verify reliability. And a somewhat elegant PCB. Parts: Perf board, 9 IR leds and photodiodes, 18 resistors (for now) and an Arduino Mini Pro. Details on my project page as usual.