Replacing Sega "Jumbo" DMD

[delarge]

All was working fine when I took the old display out. Could play a game, just some parts of DMD were hard to read due to fog and in dire need of a new display.

[Steevsee]

Sorry to keep posting, but I can't stop wondering why this display is not working.

Been going back over the thread and noticed a couple of things.

First, as far as I can tell (and I could be confused again!), the display has never been tried with the jumper and power both on position/pin 1.  The instruction page seems to indicate that this is the correct configuration to use.

Second, while looking at the pic of W1, I wondered if the jumper is surface mounted or has holes in the board.
If there are holes, did you use a wire for the jumper or just a blob of solder?
Don't mean to be rude, but the solder in the picture looks a little 'blobbish'.

Maybe just playing Devils advocate here, but I'm not convinced the new 5v cable will solve this issue.
The display driver was obviously working before, despite the low 5v.

[delarge]

Thank you for the reply! The replies give me hope.

Yes, was thinking about this today (the wire). The original configuration had a piece of wire and it wouldn't solder free, so I snipped it with some side cutters. I used a blob of solder to connect the two on the other side. Now, if I re-connect the wire on W1, will me soldering the gap in the wire work, while unsoldering the other side?

Yes, was absolutely working before with the old display.

Cheers!
Adam.

[Steevsee]

If the existing pin stumps are still present, you could definitely solder a link between them.
Adding a small wire, like a piece of a resistor leg, would be better than trying to blob the solder(though it might have more chance than last time with the existing pin stumps already making the connection to the other side of the board.

We might be clutching at straws but I think its worth a try.

Of course, you would also need to move the blue wire again(I think) to pin 1.
And obviously remove the solder bridge from position 4.

[delarge]

It's the last thing I haven't tried, so why not. Until the next exciting episode...stay tuned!

[Steevsee]

Go very easy on the heat around the pads as they have already been heat stressed once.
Good luck!

[delarge]

SUCCESS!!!

Thank you to all that persevered with this thread. I had a crash course in multimeter usage and learned about bridge rectifiers.

Moved the jumper back to the original position on the DMD. Initially, all I had to do was remove the 5V wire and put the +12V wire in its place. I don't know why the pin repair guide said I needed to stuff around with changing jumpers?

Steevsee, Beaky, Mike, Blair and anyone else that helped, I owe you a beer!

Cheers!
Adam.

[Steevsee]

 
Thank God! I can sleep tonight.

To be honest there really isn't a lot of information on these large displays on the net and what there is can be misleading.

Not having a dig at anyone, but this would have been a much shorter thread if that jumper was never moved in the first place.

[delarge]

Sorry for leading everyone on a wild goose chase. I took the pin repair guide as gospel. This was the reason why I moved the jumper:

"On newer 192x64 DMD score displays there is a jumper marked "W1 Supply
Pin". This
jumper must be set correctly or the display will not work in Sega
pinball games. The
two vertical "4" jumper pads on the left should be tied together".

Once again, truly grateful of everyone's help.

Thank you.

[Steevsee]

No worries Adam.

As I said, certainly not having a dig at you mate.

Also the reason I have been so interested in this thread, is that my display looks like it is also had it.
I've probably learned as much as you have about these large displays and as you said this may be a useful resource for somebody in the future.  So thanks for the OP.

Steve.

[delarge]

Well, I feel like I've led everyone on a wild goose chase.

Glad you might have learned something and sorry to hear about the display. Main rule: follow exactly what is on the instructions that come in the box with your new display and you can't go wrong.

 

[Homepin]

 

[delarge]

  Happy dance.

At least my voltages were checked. haha

[Steevsee]

Well, I feel like I've led everyone on a wild goose chase.

Glad you might have learned something and sorry to hear about the display. Main rule: follow exactly what is on the instructions that come in the box with your new display and you can't go wrong.

 

You should sit back, enjoy your victory and shout yourself a cold one.  You've earnt it

[Steevsee]

Happy dance.

At least my voltages were checked. haha