I posted a question on here in January in my quest to get my Apple II Europlus to boot. This machine gets power but displays a screen of alternate lines (one inverse, one not) of numbers and characters. There is no beep, and it does not drop to monitor even if I try to force this.
I pulled together the replies and other tips from elsewhere in here and performed the following work:
- I extracted the 80 column card and the 16k memory card and set them aside.
- I reseated every chip and replaced some of the Texas Instruments memory chips as they had alot of black residue on the legs and I had spare chips from the discarded 16k card.
- Most of the rest of the chips were in great shape, but the chips that had 'El Salvador' on them again had alot of residue which I cleaned off as best I could with a pencil eraser and then some isopropyl alcohol. These were mostly 74S138's.
- I dropped a spare memory chip into the slot where the 16k card piggy backed in.
- I cleaned up the machine and extracted alot of dust out of it(very carefully).
I purchased the machine as a non-runner. I noticed when I first got it that the inside of the case had some dark staining (as if the machine had gotten hot at some point).
Having re-assembled it, it pretty much did the same as before though the characters were '/s' on one line, and '2's on the inverse line except for one digit 3 on the third from bottom line.
As I now also have a working machine, I noticed that the basket case motherboard (especially around the memory chips) was getting 'far hotter' than I expected and significantly more than my working machine.
I am not keen to do a chip swap as I don't want to screw up the working machine, especially with the heating up issue. I suspect that I have two issues, heat and a faulty F0 ROM.
Any advice you guys can offer, with the heating up issue would be gratefully recieved. I wonder if I need to either scrap the machine or look to buy a replacement motherboard. If I need a replacement motherboard, can anyone recommend a source (I see the odd one on ebay, but not many, it is an 820-0044-c). I am based in the UK.
Many thanks for reading and any wisdom you can share.