NES pins or traces (I guess) seem damaged. How to fix?

Razzie.P · May 28, 2019

I have 2 older NES systems that I'd like to fix and pass on to a couple of kids who suddenly have an interest in retro gaming, thanks to youtube. I tested my "blinking light win" on them and they seem to work perfectly. However, on the pins, or traces (not sure of the correct terminology) where the 72 pin connects to the motherboard, there appears to be a couple of damaged spots. Even though these seem to work fine, is this something that will start causing an issue later? What's the correct method to fix this? Is is as simple as getting a soldering pin and filling in the bad spots, or something more needed?

I'm attaching 2 pics to show the issue. They're the same pics, but I'm circling the problem areas in one of them to hopefully better illustrate what I'm rambling about.

Thanks in advance!

+Stephen Moss · May 28, 2019

It looks like it was probably an over etching issue during production, whatever the cause I think it unlikely it would spread and the contact mark on the fingers do not appear to extend into the effected area so I would say you are OK to leave it as it is.

However, if you do want to do something about it I would first clean the finger contacts with an evaporating cleaning agent such as Isoproponal (isopropyl alcohol) and then use a conductive pen (used for small PCB repairs) as solder will be harder to keep where you want it. I would fill in the gaps with the conductive ink, if necessary building up the layers until flush with the existing finger surface, after that you may want to put a final coat over entire surface of the finger so there is a larger contact area between your repair and the finger than just the edges.

Most of the fingers appear to have a hole below them and a track linking it to the finger contact, I may be wrong but from the shape of the hole pads it looks to me like the two damaged adjacent finger should also be linked to their respective pads. I cannot see any track for that, it may just be the image but to me there appear to be damage (may just be dirt) in that area that has removed those connections so you may want to take a closer look there.

Edited May 28, 2019 by Stephen Moss