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Comment by johndoe0815 | Hacker News Reader

There were some hacks to connect an external (Hercules-compatible monochrome) monitor or a projector to a compact Mac (128/512/Plus) in the 1980s.

Building such an adapter is described on p. 168/169 in https://vintageapple.org/macbooks/pdf/Macintosh_Repair_&_Upg... and there's a thread on a projector adapter at https://tinkerdifferent.com/threads/compact-mac-video-adapte...

Great to see that this approach is still useful today!

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Somebody was getting rid of a Macintosh Classic that had a broken neck on the display tube. I built it in to a small tower case that was common in the early '90s and connected it to a TTL monitor using a 74LS14, which I think I learned about from the "Macintosh Repair & Upgrade Secrets" book. We used to call those Hackintoshes back then ;)

Fascinating! I remember seeing somebody do something similar with a first-generation iMac in the 2000s. It was kind of like a DIY Mac Mini.

Could you get color? The original Quickdraw APIs (from 128->Plus ROMs) all had library that supported a handful of primary colors, but I was never certain if there was any hardware (pre-Mac II) that could actually do anything with color.

No, this just adjusted the video levels to TTL - and you had to adjust the frequencies of the monitor since the Hercules HSync/VSync frequencies were not exactly what the original Macs generated.

The QuickDraw source code (https://computerhistory.org/blog/macpaint-and-quickdraw-sour...) definitely has some color support, I think the CHM version source code is for an early version used in monochrome Macs (but there's no version number or date given).

I believe the ImageWriter II dot matrix printer (and maybe a few third party ones) had an optional color ribbon that supported those primary colors.

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