Just noticed this tonight. Haven't had time to check voltages. Seemed weird enough I'd post and see what people in different time zone think.
Dmd looks great. Problem is on just left 10% of dmd. When a dot is active but has black (non active) on one site, it will be faint for a bit before getting full brightness.
This is easily seen in dmd diagram with the active column only. Patterns with lots of active dots are spot on.
Doesn't seem like out gassing. Thoughts?
... Altan
Took a quick video to make it more clear...
Check out...
1) Very beginning (4 seconds in) and you can see the column flickering.
2) ~27 into the video you see that horizontal lines are no problem
3) ~34 secs you see that doing columns isn't a problem when they are all active
4) ~55 secs you can see the column problem in the checkerboard pattern
In short, it seems to only be a problem for 2 columns and then only when they are active with black on either side.
Perhaps the connectors for those columns are breaking off?
Over lunch I did a quick DMD swap. Problem went away with the spare DMD. Problem returned when I put the original DMD back.
Thoughts on the weird column issue? I'm wondering if the resistors for those columns need to be reflowed? Too simple?
Didn't seem to be any reason to reflow the resistors on those two columns... resistance measured correctly from one end to the Ux chip. But I did... and it did't make any difference.
Appreciate any thoughts. I'm guessing this is just "old DMD starting to have connection issues inside the glass" --- not really outgassing.
Can you make it change at all? Does it change at all when you jiggle or press on the ribbon cable connector? If it is a cold or cracked solder joint maybe reflow the header pins for the connector.
Quoted from altan:starting to have connection issues inside the glass
sounds like it. You can try to resolder that pin going into the glass.
Though, it looks like a very good time to upgrade to color! Well, at least once displays are back in stock. HiRes and in full color for JD looks awesome. Check out the video preview.
http://shop.colordmd.com/colordmd-replacement-display-for-judge-dredd-pinball-machine/
Well... This problem has gone away as quickly as it came. Strange!
Powered on the game tonight and those two columns are just fine. Hmm....
Quoted from Taxman:Can you make it change at all? Does it change at all when you jiggle or press on the ribbon cable connector? If it is a cold or cracked solder joint maybe reflow the header pins for the connector.
No, I wasn't able to influence it by jiggle, etc.
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