Saturday, August 19, 2006
So, I have this nice monitor, a SUN GDM20D10 which relates to a old Sun workstation that is dog-slow by todays standards and which I therefore no longer use for anything. I had built a adapter-cable for it's strange connector a long time ago, but never found a graphics card that outputs composite sync signals. Those sync signals tell your monitor when it has to start drawing a new line, or when it has to begin at the top of the screen after it has reached the bottom and todays PCs usually carry those signals on separate lines. And because SUN monitors are different, they want those signals merged together on a single input pin which my graphics cards is not able to provide. (Well, it is, but there is currently no simple way to tell it to do so). I always planned to build one of the circuits whose schematics you can find on the web for that purpose, but always forgot buying the necessary parts. Now while cleaning up the cellar, I stumbled upon that lonely 47LS00 you can see soldered to the white cables and held by the oscilloscope probes. Granted, my VGA connector now looks a little bit odd, but finally it sends something looking almost like a good composite sync signal onwards to the CRT. And it's good enough to persuade the monitor to display something (and not just turn off and going into power-save-mode). Finally, no more tiny icons and blurry text on that old and crappy 17"-tube. That makes me happy.