Screen brightness too low? Okay, just whip out some ancient circuit diagrams, trace them to find the capacitor at fault, find that capacitor on the board, desolder it, test it, find that it's faulty, resolder a new one. Well that helped but it's not much better sigh. Now examine the switch, CRT tube, etc.
And here I've been known to throw in the towel when having 'this' issues in JS.
But it's not the ancestor of the computer printer.
The Selectric's main ancestor is the Blickensderfer_typewriter , from 1892. This used a curved type element rather than a typeball, but had a similar method of turning key presses into typing element positions. As with the Selectric, the font could easily be changed. There was a proportional-spacing successor to the Blickensderfer, the Vari-Typer, and IBM imitated that, too, with the IBM Selectric Composer.
The Selectric had a moving print head rather than moving paper, with cables on moving idlers used to transmit position to the print head. That mechanism is from the Teletype Model 28/35, from the early 1950s. Moving the print head rather than the paper was a Teletype concept - it worked much better with roll paper, and the machine was narrower.
The Selectric mechanism was not designed for electrical inputs and outputs. The add-on mechanism for that was an afterthought, and kind of a hack. The unit had to be built into a table, and the mechanism for the keyboard extended below the tabletop. IBM and Remington had previously built typewriters with electrical I/O, and those were used with some early mainframe computers.
Many computers, before and after the Selectric, used Teletype machines as I/O devices. That lasted until daisy-wheel printers and cheap CRT terminals were invented.
(Mechanical line printers have a completely separate history. They descend from the Potter Flying Typewriter.)
The whole world isn't quite like that yet; a few years ago I visited a factory in India that made portable generators. Aluminium ingots and copper wire came in one end and generators came out the other. None of the labor was automated. They could have, with some effort, changed products.
A. have the schematics.
B. its not just a jumbled mass of ICs.
If it's really the tube, and it's a truly rare custom tube and not just something you might be able to find a suitable replacement for, maybe these guys can help:
The last commercial CRT rebuilder for ordinary TVs in the US closed in 2010. But there's still a company that does it for military display devices that need to be kept going. "We are your obsolescence solution now and in the future."
It really is a custom tube. PARC built the first tubes in-house (PARC was also a copier R&D facility, so they could build precision optoelectronics) but then sent the job out for production.
This is a really unique piece of hardware and of course you might want to try this technique only if you have no choice.
At 7:35 he filmed in a close up the caution label on the tube backside with x-ray warning fine print
X-RAY WARNING: When picture tubes are operated above 16
kilovolts, and when personal exposure is prolong at close
range, special shielding precautions against X-ray
radiation may be needed.
Couldn't the buffer just be column-major?
There is however a possible efficiency argument: if you are more likely to write horizontal rectangles of bitmaps, then you'd want the memory word to be horizontal so you have fewer memory locations to update. Was that really the case?
UPDATE: I'm was using 2016 thinking, my bad. In those days, compared to the complexity of the rest of the system, making the CRT circuits custom was trivial. If this could, even marginally, simplify the rest of the system (not least the software), it would be the right choice.