68kMLA Classic Interface
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| AppleColor RGB Monitor Repair | |
Posted by: Sideburn on 2023-08-28 23:44:31The very top one on the H board, is the one I meant. H-Stat and V-Stat. Bottom two left pots.  After putting it all back together. My wheels started spinning in my head so of course I had to crack it open again and do a thorough adjustment based on the service manual. I downloaded the Display Service Utility as well. But first turned off all the lights in the room and set the cutoff to just when it goes black woth full contrast level. I set all of the voltages on the neck board for R G and B to 140v (they were at 160) then adjusted the colors by turning down each pot as needed. Basically had to turn red down. It looks perfect to me based on my 1990’s memories. It’s very crisp for a CRT. Much better than the ST and Amiga. The apple trinitron monitors were always excellent and flicker free. The only bummer was the top left corner of the bezel cracked during shipping but since that happened and the display was all whack the guy gave me a full refund on it. So at least I got it for free 🙂 one day I’ll probably attempt a fix of the cracked corner with some epoxy, light sanding and paint matching. Had some good results fixing a cracked 520 ST case so I’m willing to give it a shot.  | |
Posted by: Sideburn on 2023-08-28 23:45:22I’ll check those pots out. I didn’t realise there were any on the side for geometry. Here’s the service manual incase you don’t have: https://www.applerepairmanuals.com/the_manuals_are_in_here/AppleColor_High_Res_RGB_Mon.pdf | |
| Posted by: jmacz on 2023-08-28 23:46:11 Deflection board D has five pots. You need a tiny insulated screwdriver as the holes are like 2mm diameter and the case has to be off. It’s easier to adjust from the tube side of board as the pot is on the tube side. But also more dangerous as the monitor has to be on.  | |
| Posted by: Sideburn on 2023-08-28 23:49:29 Just stay away from the flyback! A couple tens of thousands of volts is not fun but a couple hundred volts ain’t no big whoop! 😂 | |
| Posted by: Sideburn on 2023-08-28 23:54:18 I remember these monitors always had a slight pin cushioning on the sides back in the day from the factory. Just a tiny bit. I always thought it looked cool. like it was supposed to be doing it because it was so high quality haha. like the top right example but much much less, Very subtle. | |
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