I opened up a functioning TI-80 (I-0695C) and noticed some of the PCB traces seemed a little odd. Upon closer inspection, the PCB appeared to have manufacturing defects that were reworked to bring into working condition. Specifically, there are errant traces at weird angles that have been manually cut to avoid shorting. I've never seen anything like this before and was pleasantly surprised they didn't just bin the botched PCB.

1. Immediately below the T6M53 ASIC, it looks like ROW1, ROW0, and VCC nets were shorted with a copule bridging horizontal trace and was corrected with cutting to separate the traces.
   
2. Just below that, ROW5 and ROW1 had a crazy angled trace shorting them and extending for several centimeters.
   
3. To the left of the T6M53 ASIC, the tip and ring nets are shorted together. This was left untouched as the graph link is not populated in TI-80 and it did not extent into the far left RAM /CS net
   

Despite all this, the rework allowed the PCB to become usable again and is actually the TI-80 that works most reliably in my collection.

I used to do rework at a PCB assembly place. we saw something similar a few times, though the fix in this case is pretty well-done - where I worked there would be a good blob of rework solder mask that never looked good. Is there any texture to the fixes? It's hard to tell from the photos.

That's interesting, didn't know how common this was. The two pictures in the original album don't show it too well, but bellow are some more photos with a slightly better camera and better lighting. There are relatively deep gouges in the board where it looks like perhaps a knife was used to separate the erroneous top traces. Full images in album if you want to see more context or detail.

I think I only saw 3 or 4 cases of this, 2 in the same batch of boards. One was easily recoverable, the other wouldn't have been acceptable after a fix. I could have got it working... but might not hold up to rough conditions the boards were used in.

The fix was basically what you see here. cut the traces with either a scalpel or dremel, make sure there's nothing shorted, then apply solder mask (we used some UV-cure stuff)

I wonder if the fact that it's a viewscreen had anything to do with the repair. Is there anything interesting/early about the date code/SN?

To clarify, this is not a ViewScreen; this is a typical consumer TI-80. The flex and wires in the pictures are my own additions for some other work I'm doing. The image album has more and larger photos of the inside and back cover. Nothing stands out to me about the S/N or manufacturing code: 06039949 | I-0695C

Wow can't say I've ever seen this before, seems rather odd to go to the trouble of rectifying it manually but good for the PCB I guess!