Simisimac w/ horizontal zebra stripes - how terminal?

badferday

Tinkerer
Jan 26, 2024
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I've seen this state referred to as terminal. But... how terminal really? Terminal can mean it's fully dead and needs work. Or it can mean hopeless. Know what I mean? Because I don't! Someone tell me.

- Katrina
 

caver01

Tinkerer
Oct 30, 2021
93
63
18
I think it varies by system and root cause. In my case, my SE/30 was exhibiting this issue and it eventually led me to replace a video mux chip if I recall, not to mention a complete recap and all of the cleanup that goes along with that. In the process of eliminating the problems, I had to remove the ASC sound chip, add bodge fixes on SCSI lines, and even had to run a bodge from front to back because of rotten/missing traces and vias. Along with troubleshooting the analog board, it took me a year to fix my SE/30. Was my simasimac symptom terminal? It might have been with less patience, but theoretically, if you can find and fix all of the contributing issues, it's not hopeless at all.

It could have been a lot worse too, like bombed battery issues or just too many chips to replace and broken traces to correct. I guess what I am saying is terminal for some people is just an added challenge for others.

I repaired a Classic in similar fashion exhibiting simasimac symptoms. Again, it was several bodge fixes over rotten traces and a recap (of course).

I have seen plenty of examples in my research to fix my own issues where a recap and cleanup was all that was required. YMMV, but I might take the plunge again someday if I come across a simasimac system that needs help.
 

badferday

Tinkerer
Jan 26, 2024
175
42
28
I think it varies by system and root cause. In my case, my SE/30 was exhibiting this issue and it eventually led me to replace a video mux chip if I recall, not to mention a complete recap and all of the cleanup that goes along with that. In the process of eliminating the problems, I had to remove the ASC sound chip, add bodge fixes on SCSI lines, and even had to run a bodge from front to back because of rotten/missing traces and vias. Along with troubleshooting the analog board, it took me a year to fix my SE/30. Was my simasimac symptom terminal? It might have been with less patience, but theoretically, if you can find and fix all of the contributing issues, it's not hopeless at all.

It could have been a lot worse too, like bombed battery issues or just too many chips to replace and broken traces to correct. I guess what I am saying is terminal for some people is just an added challenge for others.

I repaired a Classic in similar fashion exhibiting simasimac symptoms. Again, it was several bodge fixes over rotten traces and a recap (of course).

I have seen plenty of examples in my research to fix my own issues where a recap and cleanup was all that was required. YMMV, but I might take the plunge again someday if I come across a simasimac system that needs help.

Thank you. That's very helpful, indeed!

I'm gonna drive 2 hours if the seller accepts my offer, so, yeah... hahaha.

This is the actual device in question going Full Zebra mode.

1708979528313.png
 

caver01

Tinkerer
Oct 30, 2021
93
63
18
Was looking up examples where folks call this "terminal" and I think another reason is that the fix is sometimes replacing RP2 Bourne filter? I don't recall having to do that myself, but those parts were/are apparently hard to find in low quantities, so it was often easier (cheaper) to pull them from a donor system. Unfixable? Certainly not. A bit like a car that gets "totaled" simply because accident damage exceeds its value, even though it might be fine someone took the effort to get the parts and fix it.
 

badferday

Tinkerer
Jan 26, 2024
175
42
28
Was looking up examples where folks call this "terminal" and I think another reason is that the fix is sometimes replacing RP2 Bourne filter? I don't recall having to do that myself, but those parts were/are apparently hard to find in low quantities, so it was often easier (cheaper) to pull them from a donor system. Unfixable? Certainly not. A bit like a car that gets "totaled" simply because accident damage exceeds its value, even though it might be fine someone took the effort to get the parts and fix it.
Nice.

What would you say is a fair price on this SE/30? It also comes with the mouse and the Apple ergononmic keyboard.
 

robin-fo

Tinkerer
Feb 17, 2022
96
49
18
Switzerland
If it‘s a SE/30, are you sure the RAM is compatible? I also had these stripes on mine despite known-good RAM. I tried different modules, and it booted..
 

Bolle

Tinkerer
Nov 1, 2021
46
74
18
Those stripes are the default contents of the VRAM. (depending on the vendor of the VRAM the default contents can also be thick horizontal stripes - yours are the thin variant - or gray background with vertical lines of garbage that are 1 pixel in width)
What that means is that the board didn't get to the point in the boot sequence to initialize the VRAM with the gray background that you usually see when a 68k Mac first displays an image on screen.
Not reaching that point in the boot sequence can have multiple causes... ranging from a simple "ROM SIMM is making bad contact and just needs to be wiggled a bit" to total battery destruction and basically everything in between.
 
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badferday

Tinkerer
Jan 26, 2024
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Well, she's on the way! As is my ColorRadius Pivot and SE/30 card. It's gonna be an interesting weekend!
 

caver01

Tinkerer
Oct 30, 2021
93
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Nice.

What would you say is a fair price on this SE/30? It also comes with the mouse and the Apple ergononmic keyboard.
I might not have the best answer here since mine was a (broken) hand-me-down from my dad (free + repair parts). The repair parts may or may not be a consideration for you.

I have seen broken SE/30s sell for hundreds of dollars if they are not completely battery bombed. They are unique and rare enough now that people are willing to pay more for them than you might for a more typical flavor of SE. Case in point, I paid $150 a couple years ago for a carload that included a classic, four SE's (non FDHD), three SE logic boards, a broken Plus, a couple keyboard IIs, and a bunch of SCSI drives, a pair of HD20s (external), an external floppy. . . . But, there was not an SE/30 in that group. There are deals out there like my carload if you are willing to drive, but I think an SE/30 puts all of this bargaining on its head.

Perhaps others will chime in with their SE/30 price tags.