Well folks, it was a false alarm. My wife was looking at my open switches and told me to zoom in with my camera. It turned out that it wasn't the dome itself. The dome had left just enough residue on the switch contacts to prevent consistent usage. So I sprayed excess contact cleaner and a qtip and cleaned it vigorously. Voila, all three switches work perfectly.
It took a better part of five hours to do all of them. I figure this would likely happen again. And I was concerned the self adhesive version would break off during use but, no. The material in the domes is self adhesive. The dome material was also cast to be quite flat. I didn't have to use any of the new bits since it's still in shipping from amazon. But, I have them in stock because there are a number of 100s I will be refurbishing for resale at some point. I'm glad the wife looked at it with her eagle eyes. I would've torn off the original stuff and it wouldn't have worked. I would have kicked myself. I also replaced the leaky battery on the mobo so she's ready for modifications! Looking forward for this project. Daniel sysop Air & Wave BBS finger [email protected] On November 26, 2025 5:04:11 AM PST, me--- via cctalk <[email protected]> wrote: >I just acquired a TRS-80 model 102, my first of that model. > >Everything is great other than three keys. The 2 keys works intermittently, q, >and [ don't work. Having checked the schematic, the keys have no commonality >on the circuit. > >Before I pull the cap off the switch, I know that the rubber dome inside has >material on the inner part that meets with the silver contacts to complete the >circuit. I'm told this material will wear out or lose conductivity. > >I reflowed the solder joints on the pcb and this didn't help. Other people >have simply replaced the rubber dome from another dead 102's keyboard. But, >I'd rather attempt applying new material inside that dome. > >I'm hoping there is an inexpensive and mainstream solution I can buy at home >depot or something. > >Any tips? > >Daniel >sysop | Air & Wave BBS >finger | [email protected]
