I have an Apple II with the DC-51 keyboard that has the encoder on the main board. It was working, other than the usual bad DC-51 switches. It sat for a while, and I've just installed a new-old-stock DC-51 for the O key. Now I'm having issues with certain keys (O P ; : /) outputting strings of garbage. All other keys seem to work fine. I tried cleaning and reseating the encoder, but I'm not sure what else to check right now.
Checking the schematic does show those keys all on X3 on the encoder chip. The traces seem to test fine, but I'm not 100% sure I'm hitting the right spots or know for sure how they should test. Does anyone know if that sounds like the issue or is it possible the encoder has failed?
Edit: Pressing P outputs N,O,P, and 9 in various orders. I checked the encoder lines for 9 when pressing it, and it doesn't pop up. Holding the bad keys and checking the encoder pins doesn't show any active other than the ones that should be.
Thanks!
Checking the schematic does show those keys all on X3 on the encoder chip. The traces seem to test fine, but I'm not 100% sure I'm hitting the right spots or know for sure how they should test. Does anyone know if that sounds like the issue or is it possible the encoder has failed?
Edit: Pressing P outputs N,O,P, and 9 in various orders. I checked the encoder lines for 9 when pressing it, and it doesn't pop up. Holding the bad keys and checking the encoder pins doesn't show any active other than the ones that should be.
Thanks!
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