Double Dragon boardset: what is this component?

MaximRecoil

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It is attached to the board by little posts. On my board, a few of those little posts are broken. Is that anything to worry about?
 
That is what is referred to as a rail. It connects a particular circuit across the board. Check for continuity from one of the connected points to where it is broken loose. If there is continuity then you should be OK. If not then you need to repair or replace the rail.
 
That is what is referred to as a rail. It connects a particular circuit across the board. Check for continuity from one of the connected points to where it is broken loose. If there is continuity then you should be OK. If not then you need to repair or replace the rail.

Thanks. I do get continuity though I'm not sure how. It must be connected in ways other than just the rail. The game works fine too.

I'd like to replace it anyway. Is it a standard part or is it custom made for the Double Dragon board?
 
If the rail is not a standard component, wouldn't a series of jumper wires soldered into each through-hole point work just as well?
 
If the rail is not a standard component, wouldn't a series of jumper wires soldered into each through-hole point work just as well?


Yes, I have done that and it worked fine.

The reason you have continuity is because the rail is designed to handle a higher amperage load. The designer was concerned that the on-board traces were too small to handle the amperage required and so the rail was added in order to overcome this shortcoming. There are still traces present that connect this line (my guess is +5vdc) but they may be insufficient, especially if the board is on for a long time and heats up.
 
Yes, I have done that and it worked fine.

The reason you have continuity is because the rail is designed to handle a higher amperage load. The designer was concerned that the on-board traces were too small to handle the amperage required and so the rail was added in order to overcome this shortcoming. There are still traces present that connect this line (my guess is +5vdc) but they may be insufficient, especially if the board is on for a long time and heats up.

Thanks. I'm going to see if I can top-solder the broken points in place first. The through-holes are pretty small, and I don't think I have any wire small enough on hand to work as a series of jumper wires.
 
Thanks. I'm going to see if I can top-solder the broken points in place first. The through-holes are pretty small, and I don't think I have any wire small enough on hand to work as a series of jumper wires.


Actually, I soldered in some old scraps from cap legs and then wire wrapped a non-insulate solid wire between each post. It is not pretty, and it may shock someone who inadvertantly touches it (very slim chance), but it is functional.
 
I found some wire that would fit and daisy chained it in the 6 through-holes that weren't connected to the rail, and tied it into the first unbroken leg of the rail. I then got perfect continuity between all points on the rail and the jumper wires; much better continuity than before.

Small problem; now the board won't work (I hate this hobby sometimes). I guess I need to start a new thread.
 
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