[cctalk] Re: ADM-3A keyboard improvements?

Does it get better, or WORSE, with extended use? Sometimes, oxidized or dirty contacts clean themselves a little with more use, and are especially bad with non-use. 40? years ago, I was handed a "dead" TRS80 keyboard. After repeatedly beating on one key, it gave a hit! And, would work a small part of the time. I tried with others, and determined that extended excessively heavy use seemed to re-enable keys, at least sporadially! So, I dug out a Rochester Dynatyper Keyboard Actuator. It was like the KGS80, a box of solenoids intended to be set on top of a typewriter keyboard to turn a typewriter into a cheap printer (back when "cheap" computer printers were a thousand dollars). Those would "print" relatively reliably at about 8 characters per second. There also existed the Escon (Walnut Creek) Model E-P, which was the same idea but Selectric specific, and mounted inside the Selectric, and pulled the keys down; that could almost handle the 14.8 characters per second maximum of Selectrics. I set the Rochester on top of the keyboard, and sent enormous text files to "print". After a while some of the keys were working! By the next morning, they all worked! Before trying that, consider that if the problem is mechanical, it might help those keys, or it might wear them out, and finish killing them. -- Grumpy Ol' Fred cisin(a)xenosoft.com On Tue, 6 Oct 2026, Charles Morris via cctalk wrote: > I'll check the p/s, but since everything else works correctly, I suspect > dirty key contacts and a poor debouncing circuit. > Pressing (for example) the "2" key,  sometimes it outputs "22", > sometimes "2v"... the debounce circuit should take care of the first, > and the second has falsely set bits (0x32 vs 0x76). > Some of the other keys have either or both errors too - will have to log > the errors associated with each key and see if I can find it in the logic.