sev
Experienced Member
So I picked up an Apple III today, serial number is in the 30k's. When I tested it at the buyer's house, when I first turned it on, the picture was jumbled (due to bad NTSC signal), so i Re-seated the connector and it booted up to the memory diagnostic, but I didnt let it run all the way and shut it down.
So I brought it home and booted it, and now during boot, and pretty much always, the screen is filled with P's from top to bottom. The drive tries to seek at boot, but all the test is garbled on the screen. I'll post a youtube video showing what I mean.
I took it apart and pushed down gently on every chip, some of the memory chips were a tiny bit loose, but not enough to lose contact. I tried booting it, but no difference.
I went ahead and pulled the ram board, which appears to be a 12v ram board, I think with 256k. I removed each ram chip, cleaned a few and replaced each one. I noticed there were several different manufacturer of ram chips, the ones that were from ITT had very clean pins. One was from Motorola and that was clean too. The chips from TI had this dark black corrosion on them, almost as if they had gotten too hot. I cleaned them as best as possible and replace. The system still does the same thing
Also to note, the power supply has a faint sound, not sure if this is normal.
I tried putting it into diagnostic mode but it just freezes.
i'd love to get this thing going... I'm very new to the AIII... Any help would be greatly appreciated!!
https://youtu.be/kjEG8cVpSOE
So I brought it home and booted it, and now during boot, and pretty much always, the screen is filled with P's from top to bottom. The drive tries to seek at boot, but all the test is garbled on the screen. I'll post a youtube video showing what I mean.
I took it apart and pushed down gently on every chip, some of the memory chips were a tiny bit loose, but not enough to lose contact. I tried booting it, but no difference.
I went ahead and pulled the ram board, which appears to be a 12v ram board, I think with 256k. I removed each ram chip, cleaned a few and replaced each one. I noticed there were several different manufacturer of ram chips, the ones that were from ITT had very clean pins. One was from Motorola and that was clean too. The chips from TI had this dark black corrosion on them, almost as if they had gotten too hot. I cleaned them as best as possible and replace. The system still does the same thing
Also to note, the power supply has a faint sound, not sure if this is normal.
I tried putting it into diagnostic mode but it just freezes.
i'd love to get this thing going... I'm very new to the AIII... Any help would be greatly appreciated!!
https://youtu.be/kjEG8cVpSOE
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