Howdy, I did a recap of the analog board of my SE/30 recently and since then it is intermittently typing the letter “t” over and over — like it’s a stuck key. When it does this, typing on the keyboard seems to cause it to stop temporarily; however, it will insert an errant “m” at random in between keystrokes. After a few minutes, it will start typing “ttttttt” again. Everything else seems to be functioning normally. I initially thought it was a fault with the keyboard, but even with the keyboard unplugged, it still exhibits the same behavior.
Couple of notes:
After reading up on the ADB protocol, it seems like it’s susceptible to RF interference, so that’s my working theory, but any and all feedback/advice is much appreciated!
Couple of notes:
- While recapping the analog board, I did make the mistake of installing one capacitor backwards, which promptly let out the magic smoke a few seconds after the first power-up. I thought that was the cause, but I replaced it, and the issue persists.
- The logic board was recapped a couple of months ago.
- I recapped the (Astec) power supply this weekend.
- The issue happens when booting from a floppy or BlueSCSI.
- The machine is bone stock with the exception of upgrading to 8MB of RAM.
- The power supply voltages have been measured and appear to be within the specified ranges.
After reading up on the ADB protocol, it seems like it’s susceptible to RF interference, so that’s my working theory, but any and all feedback/advice is much appreciated!
