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Mac SE CRT COLOR!
Posted by: techknight on 2011-04-15 20:33:30
Well, not really using a mac SE.

but i used a CRT from a Mac SE, Analog VGA circuits, one big ass color wheel, syncro circuits built on a breadboard, and VGA output from a laptop.

Mac SE CRT is now COLOR

This is what happens when you get bored, have alot of spare parts, and free time on your hands. I did this color wheel setup back in 2007.

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DSC00404.JPG
Posted by: LCGuy on 2011-04-16 10:24:11
What I'd like to know is how you get colour on a monochrome CRT...given that a monochrome CRT doesn't have red/green/blue guns, the most you should be able to get on one is greyscale. (as seen with the Micron XCEED greyscale adapter as used on the SE/30)
Posted by: Trash80toHP_Mini on 2011-04-16 10:42:41
WT . . . 8-o

Posted by: Gorgonops on 2011-04-16 13:36:55
What I'd like to know is how you get colour on a monochrome CRT...given that a monochrome CRT doesn't have red/green/blue guns, the most you should be able to get on one is greyscale. (as seen with the Micron XCEED greyscale adapter as used on the SE/30)
Note the giant color wheel? It's "time-multiplexing" the monochrome CRT by sequentially using it to provide the luminance value for the three primary colors. (Which exist as colored windows in the spinning wheel.) The setup here is similar to the CBS Field Sequential Color System proposed in 1949... and incidentally, similar to the system used in single-element DLP projection TVs.

And it's *totally awesome*. Bravo!
Posted by: techknight on 2011-04-16 21:37:58
the CRT was pulled from a mac SE because not only was the system board bad, but the CRT had severe burn in. The original CRT of the analog circuits that i used, was the wrong color phosphor for the silkscreening of the color wheel.

So it turned out to be a perfect candidate for this experiment. I did this about a year or so ago. Now, the CRT developed a hairline crack around one of the neck pins, and has aired out. which sucks. Ill have to pick another one up on ePay when i get around to playing with this again.
Posted by: Bunsen on 2011-04-20 15:27:28
That is phenomenal.
Posted by: olePigeon on 2011-04-29 17:01:38
That is awesome. 😀

Posted by: LC_575 on 2011-05-17 14:19:01
I propose a name for our future color SE/30:

The SE/30c

It's so Apple, isn't it?
Posted by: ~Coxy on 2011-05-17 20:06:32
SExc :-*

Posted by: techknight on 2011-05-17 20:08:55
Its not so un-feasable to convert an SE to color, using its original drive electronics. it is impracticable with a big color wheel.

all you need is a PDS color capable videocard, and then using a tektronix LCD based color-shutter (instead of my big ass color wheel) you could produce RGB.
Posted by: Bunsen on 2011-05-23 13:01:03
You mean like part no. CS-0010 here?

This thread is the sixth Google hit for tektronix LCD color-shutter }🙂

Meanwhile, I'd be very interested in any documentation you made on your homemade drive electronics.
Posted by: techknight on 2011-05-23 20:39:47
Yea, i need to make a good electronic schematic. the stuff i have is all hand-drawn and the motor servo is actually microprocessor controlled using an AVR and two timers. and comparing the reference timer to the feedback timer, and adjustment as necessary.

As far as the color shutter, i found out its just red/green only. it doesnt have blue....
Posted by: jruschme on 2011-05-24 03:13:30
Impressive i a sort of post-Dieselpunk way. Basically, it's what you'd get if you took a left turn at the development of color TV and then carried through to the personal computer era.
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