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Mega Drive Circuit Board Repairs

A bunch of Sega Mega Drives came via the workbench recently, all looking for a 50/60hz mod and region unlocking. Two older Mega Drive 1s were in the batch and the first modded with zero concern. Unfortunately, the second wouldn't even boot... a quick opening of the case saw the reason:

This area of the circuit board is easily accessible from the cartridge slot and I can only assume that a screwdriver (or other sharp object) has been jammed in at some point, destroying a few traces. You'll also notice solder to the left, but that was me in a previous attempt to repair this. I tried again as I now have a USB Microscope and it really does work well for reviewing damage and making intricate repairs!

How not to repair it

I first-up thought I'd be able to use copper winding wire and simply solder to each pad where the IC contacts the circuit board.

From the shots above, you can see how quickly that process failed. The combination of using a soldering iron under a microscope, a large soldering tip and shakey hands meant that solder spread everywhere. Fortunately, solder wick cleaned all that up in no time.

Also how not to repair it

The next method was a little dodgy, but proved successful. From above, I knew i needed more room to solder, so the goal was to create this room by lifting and spreading the pins and running wires to the other end of the traces.

A multimeter found the other end of the traces and winding wire was attached.

Thanks to the tiny tweezers in the iFixit kit, I was able to bend, lift and then straighten the leftmost leg.

From there, the other legs were lifted easily.

Finally, they were all spread out both horizontally and vertically to make soldering as easy as possible. I then connected the right-most as it was only going as far as the local via.

With the wires hideously attached, I considered bending the legs back down... But a blind person could see my dodgy soldering job would make contact.

Instead? Glue gun to the rescue! Finally? Test. It worked!