I have been a video guy for several years but have, finally, started to wander into pins. Everyone said it would happen...but I digress. I have acquired a few recently. All needing work to some degree. The first one I have actually started to work on is an Addams Family. One of its issues was a dead column in the DMD. Below is a copy and paste of a thread I posted on the Pin forum over at KLOV. Pinside being pinball oriented I though it may find some use here as well.
Something I thought I would share in hopes it helps someone else. In working on my Addams Family I realized I had a dead column in the display. Looking around online I have seen where folks had fixed dead rows or columns on various Dot Matrix Displays. The most common "How To" to find seem to be of a type that uses a wide ribbon cable to the glass from the board. Not sure of the brand. Over time the wire from the ribbon cable breaks at the glass and you end up with a dead line. The solution is to Dremel out the glass, expose the wire, and in some form or fashion, remake the connection.
In my situation I have a Cherry DMD with a PN of 0001-4205-B on it. Actually, I have 2 at hand. One, the one with a dead column, is in an Addams Family. The second is in a High Speed 2, Getaway. These DMDs have a pin that comes from the board that then flattens out and take a 90 degree bend that is then sandwiched between the 2 layers of glass which makes up the display. Looking through the front of the display you can see where another "contact", the lead to the actual row/column, laps across this pin. I am not sure how they are connected other than via applied pressure from the 2 layers of bonded glass.
Here is what you will need for the fix:
-Short piece of 20 or so gauge wire.
-Dremel or some other rotary tool with a small diameter diamond chip coated bit.
-Alcohol and some Q-Tips.
-Conductive paint like from a window defogger repair kit.
-Small paint brush.
-Hot glue gun.
Nice to have:
A magnifying glass or visor.
Some dental picks.