beachycove
Well-known member
A Mac 128k that starts up and displays the Sad Mac with vertical lines has what- capacitor failure? A friend has asked, and I have never even seen one of these before, so any help would be appreciated.
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Mac 128k Sad Mac and Faint Vertical Lines
- Thread starter beachycove
- Start date
The Mac 128K doesn't have surface mount electrolytic capacitors on the logic board, so it does not fail in that manner the way the SE/30 is prone to.
Could be the capacitors on the analog board, in which case it'd be more generally, a lack of proper power.
Do you have a copy of Pina's "Dead Mac Scrolls"? I'm pretty sure this failure mode is covered in there.
Could be the capacitors on the analog board, in which case it'd be more generally, a lack of proper power.
Do you have a copy of Pina's "Dead Mac Scrolls"? I'm pretty sure this failure mode is covered in there.
Mac128
Well-known member
More details please. This is not a common problem. Vertical bars would indicate incorrectly installed ROMs, but since you don't tell us if this is a new acquisition or something that happened since the last time you used it ... well you see the problem here. And what is the Sad Mac code?
beachycove
Well-known member
I haven't actually seen the thing, but the chap whose PB170 I have been working on has just gotten a Mac128k boxed with all accessories, but that is behaving in the way described.
Sad Mac code is 04038C.
Sad Mac code is 04038C.
Paralel
Well-known member
If it has been sitting in someones basement/attic for all these years it has been subjected to many seasonal thermal cycles. It definitely possible the ROMs could have creeped their way out of the sockets causing some kind of weird ROM error.
Give the old Apple III method a shot
If I'm reading this correctly:
http://support.apple.com/kb/TA46376
It failed the memory test, most likely due to a chip that has crapped out.
Give the old Apple III method a shot
If I'm reading this correctly:
http://support.apple.com/kb/TA46376
It failed the memory test, most likely due to a chip that has crapped out.
JDW
Well-known member
With only 3 electrolytic caps on the logic board, and with an absolute dearth of reports of bad caps bringing down these boards, it is unlikely bad caps are the root cause of your problem. Nevertheless, those 3 electrolytics do have meaning, and the fact is that by now all 3 are certainly on their last legs, if not dead. That's why I replaced mine with tantalum versions. You can read more about this in the description under my 128k logic board photo. (Don't forget to click "ALL SIZES" to see the large size.)
