Guess what's wrong with my TS1000

[monzamess]

The modulator can be the cause of some video picture distortion.

I can't really tell from the photo you posted.

Mark

The degradation appears as solid black and white lines running across each character cell, one scan line high, randomly appearing. Seems like a problem in image generation, thus my fixation on the ULA...

[monzamess]

Conclusion: I still think it's the ULA but I'm not sure. I bought a second "like new in box" TS 1000 and I'll use that going forward for my TS 1000/ZX81 adventures. I don't want to risk damaging its good ULA by swapping it into this TS 1000.

Also, by reading old threads on this forum, I found a different way to fix my keyboard cable problem. I unsoldered the cable connectors, moved them closer to the keyboard (taped to the lid with painter's tape), and used cabling from there to the motherboard.

first ts1000 kbd1.jpg (149.32 KiB) Viewed 1679 times

first ts1000 kbd2.jpg (159.51 KiB) Viewed 1679 times

So now my keyboard works with the case all closed up. I actually broke line #8 on the bigger ribbon cable right at the keyboard membrane--UGH--during my various misguided attempts to resolve the original problem, so that is fixed with a conductive pen for now (you can see the "blob" in the picture). I also put heat sinks on the ULA as a last resort. I read the old threads about that as well, but figured I would give it a shot.

This computer, as my very first computer, is being packed away or put on display or something. I just wanted to fix what I could before I retired it. It works fine--in short sessions.

[monzamess]

And here's the new TS 1000, which I just fitted with PokeMon's keyboard upgrade and composite video, and equipped with the ZXpand+ for new adventures. Yeah, I need a new place to put it.

classic comps.jpg (94.9 KiB) Viewed 1679 times

[1024MAK]

If you move that laptop out the way, the TS1000 and the TV may squeeze in the gap

Mark