The Tech2 is (sort of) working. My soldering skills are not good. I'm a bit too keen on "making sure" and either dumping too much solder on the joint and/or overheating things. I learnt my soldering on copper piping with a blowlamp!
I took a chance on the capacitor after I found that the Tantalum ones are known to fail all on their own, especially the cheap ones. I got a strip of 10 from RS Components. The cap was soldered in gently and seems to be firm. I then threw caution to the winds and replaced all 13 short wire between the main board and the display.
I thought about the hole in the ribbon and tried same small staples across the gap. It was put back together, but something was jamming the PCMCIA card. Another attempt and it all went together.
I now have a machine that lights up and appears to be OK, but the keypad is intermittent. A new keypad is on order from China, but will take a while. In the meantime, I'm going to try some electrical conducting paint. A tube will be ready for collection from RS Components tomorrow. I'll dot it around the point the staples go through the ribbon tracks.
Wearing two pairs of glasses helps with all this!
Picture of the ribbon
And a picture of the display as it is now. You can just see the new capacitor at the bottom.