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Thread: Does anyone have an IBM EGA board for a good price?

  1. #21

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    I ordered an EGA wonder off of eBay, we'll see how it does hopefully better.

  2. #22
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    I'd love to actually see a video of what 350 line EGA modes look like interlaced on a CGA monitor. The manual claims it can make the whole 64 color EGA palette available despite only having RGBI wiring, the only way I can possibly imagine that working is if it's effectively displaying a 1280x350 display with each doubled sub-pixel representing the low intensity and high intensity portion of each RGB component. Or something crazy like that.

  3. #23
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    Quote Originally Posted by alank2 View Post
    I ordered an EGA wonder off of eBay, we'll see how it does hopefully better.
    I really like my EGA Wonder. Haven't fully tested it to its potential but it's worked perfectly with 3 different monitors after I changed around the dip switches. Here's a pic of it in EGA on a 5153 CGA monitor
    20190607_185553.jpg
    Last edited by RadRacer203; June 7th, 2019 at 02:58 PM.

  4. #24
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    Quote Originally Posted by Eudimorphodon View Post
    I'd love to actually see a video of what 350 line EGA modes look like interlaced on a CGA monitor.
    It's not pretty. It is effectively interlaced in 350-line mode and the 5153's dot pitch isn't fine enough to really make it work. The extended colors are obtained via dithering across time, and the fast phosphors create a distracting flickering. It's a dancing bear trick in hardware.
    Offering a bounty for:
    - The software "Overhead Express" (doesn't have to be original, can be a copy)
    - A working Sanyo MBC-775, Olivetti M24, or Logabax 1600
    - Documentation and original disks for: Panasonic Sr. Partner, Zenith Z-160 series
    - Music Construction Set, IBM Music Feature edition (has red sticker on front stating IBM Music Feature)

  5. #25
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    Quote Originally Posted by Trixter View Post
    It's a dancing bear trick in hardware.
    Yeah, I figured it would be something more remarkable for the fact that it *can* do it rather than how well it's actually done. (400-line modes on an original Amiga give me a massive headache in, hardly exaggerating here, mere seconds.) But it's still cool that it can do it rather than just blindly flipping into a mode your monitor can't handle like a real EGA card will if someone pokes the registers directly.

    How it can emulate EGA modes on MDA monitors is probably a more useful stupid pet trick.

  6. #26

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    Quote Originally Posted by Eudimorphodon View Post
    I'd love to actually see a video of what 350 line EGA modes look like interlaced on a CGA monitor.
    Not quite but there is a picture in this article of a modified IBM5153 CGA monitor, that auto-detects EGA, scan converts to 28.5kHz & does a color 6 fix to display a reduced in size 16 color EGA image. Its really nice to have this because if the software in use forces the video card into EGA mode, the image on a CGA monitor scrambles and you cannot see what you are doing. The theory behind the conversion is explained in the text. The EGA screen images are on pages 18 & 19 or thereabouts:

    http://worldphaco.com/uploads/INCREA...OR_TO_AUTO.pdf

  7. #27

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    If the parts/gerber's/pcbs were available, I'd probably try to build that for my 5153!

  8. #28

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    Quote Originally Posted by alank2 View Post
    If the parts/gerber's/pcbs were available, I'd probably try to build that for my 5153!
    I don't have the Gerbers, the pcb maker I sent it to (as a jpeg drawing) somehow copied it into Altium to make it. But the project is there is anybody wanted to make it into a kit etc, but one has to be pretty confident and familiar with video monitors to install it as there is no room for any error, or it risks damage to the monitor.

  9. #29

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    Did you try it on a 5153? Do you have any spare pcb's (usually you order them in qty 10 or sometimes qty 5)....

  10. #30

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    Quote Originally Posted by alank2 View Post
    Did you try it on a 5153? Do you have any spare pcb's (usually you order them in qty 10 or sometimes qty 5)....
    Yes it was only for the 5153 monitor. I just had the one pcb made. I usually do that for most of my one off projects because I find prototype boards a bit messy and they lack a professional finish. I figure if anyone else in another country wants to make the thing, they probably would use their own pcb maker anyway.

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