Hello everyone,

This has been a long time coming... presenting the Macintosh SE/30 Vertical & Horizontal Bars on Display "Simasima" Repair Guide!! [party]



This is a FREE downloadable PDF document (~55 MB) filled with high-resolution pictures and technical details. You can find this PDF file attached to this post.

I can't take sole credit for this guide, many talented people and individuals contributed to this guide. This guide would not exist without the amazing efforts of the many geeky individuals in the vintage Macintosh and electronics community. While it would be impossible to name everyone individually, these fine folks know who they are. [heart] (and you can find some them mentioned in the guide!)

This is an early release of this guide, consider it a beta release. There are some areas that are still a work in progress, refer to page 5 to learn more about that. So apologies if anything is missing, inaccurate or broken, but perfect is the enemy of good.

As updates happen, they'll be logged at the end of this post.

What's included in this guide:

This comprehensive 112-page guide provides expert-level guidance on this common issue. Containing sections on:

1. Theory of the issue
2. Things to check first
3. Troubleshooting & Repair
4. Recommended Tools
5. Clock signal references
6. Resources and helpful links, including the redrawn schematics

What's next?

if you find this guide useful, have success stories related to it, feedback or corrections - please post them in this thread! Be mindful that not all replies can be addressed or reflected in the scope of this document.

Since all future revisions of this guide will be attached to this first post, we kindly ask that instead of sharing the PDF to others, please share this link to ensure they always have the latest version.

There are a number of things we'd like to add to this guide, but for now this makes a very solid first edition.

Thanks again to EVERYONE who helped, this was a monster effort that took years to prepare and I'm super happy to post the initial version here for all to enjoy. [party]

-Steve


Version history & notes:

• October 9, 2025: v0.9a Initial beta release (archived)
• October 25, 2025: v0.9b 2nd release (attached to this post)
  • Changes: Fixed typos, added Table of Contents, added page numbers, cleaned up and consolidated pages, added additional tools information, added links to videos and other resources.

This is amazing work! Good job to all those that contributed. I will link this page on the SE/30 page on my website :)

woah, many many thanks to everyone for the combined effort! def a jewel to have here!

Excellent work everyone! This is a lot more detailed than any guide I have ever seen! I also agree, the Conair Blue Bird is a good blowdryer.

>> Mac84 said:

Hello everyone, This has been a long time coming... presenting the Macintosh SE/30 Vertical & Horizontal Bars on Display "Simasima" Repair Guide !! View attachment 23683 This is a FREE downloadable PDF document (~55 MB) filled with high-resolution pictures and technical details. You can find this PDF file attached to this post. I can't take sole credit for this guide, many talented people and individuals contributed to this guide. This guide would not exist without the amazing efforts of the many geeky individuals in the vintage Macintosh and electronics community. While it would be impossible to name everyone individually, these fine folks know who they are. (and you can find some them mentioned in the guide!) This is an initial release of this guide, consider it a beta release . There are some areas that are still a work in progress, refer to page 6 to learn more about that. So apologies if anything is missing, inaccurate or broken, but perfect is the enemy of good. What's included: This comprehensive 112-page guide provides expert-level guidance on this common issue. Containing sections on: Theory of the issue Things to check first Troubleshooting & Repair Recommended Tools Clock signal references Resources and helpful links, including the redrawn schematics What's next? if you find this guide useful, have success stories related to it, feedback or corrections - please post them in this thread! Be mindful that not all replies can be addressed or reflected in the scope of this document. Since all future revisions of this guide will be attached to this first post, we kindly ask that instead of sharing the PDF to others, please share this link to ensure they always have the latest version. There are a number of things we'd like to add to this guide, but for now this makes a very solid first edition. Thanks again to EVERYONE who helped, this was a monster effort that took years to prepare and I'm super happy to post the initial version here for all to enjoy. -Steve Version history: October 9, 2025: v0.9a Initial beta release Click to expand...

WOOT!
I'm so happy to have resources like this! Thank You!

Typographical error on page 10:

"ROM is not napped into address $0 by the VIA, so the CPU cannot find any ROM code."

@Mac84 , you're a star! [star]

Many years ago, one of my SE/30 boards showed the exact pattern shown below, and at the time I posted in another forum to ask if anyone had seen that instead of the regular horizontal stripes, but no one replied back to say they did. Thanks to your Repair Guide, I see it is simply another variant of the horizontal stripes, differing due to the VRAM being NEC. Great info! (Still haven't read it all, but slowly making my way through it). Kudos!



UPDATE: Just finished going through the entire document. Fantastic work, especially the oscilloscope screenshots showing the signals to look for. That info is extremely helpful!

>> Mac84 said:

This is a FREE downloadable PDF document (~55 MB) filled with high-resolution pictures and technical details. You can find this PDF file attached to this post. Click to expand...

aaaaand this would be precisely the kind of reason I'm glad I found these forums. Kudos to all the contributors! You're making life more wonderful for all of us.

Thank you everyone for the kind words! I'm super glad people are finding this useful and valuable! [heart]

I hope to release a fast follow update this weekend that corrects some typos, adds some additional links/videos/tools, and cleans things up a bit... thanks again for the positive response. [+1]

Few items I just purchased to work on my SE/30 that worked last time I put it away and now no longer works:

20" ATX extender cable for $4+s/h

50Mhz 2ch Oscilloscope

Very detailed document. Amazing work!

Thanks for this very very nice document - just buy me an SE/30 with some battery damage but it was on storage sinds 1995 with the screen face up so the damage is on the battery holder mainly (its gone) and some rust on the metal case, order some part (logic first) DigiKey USA -> The Netherlands (waiting for now) and see if we get an normal image to start..

Update! A second release, v0.9b has been released! [party] This revised PDF is now attached to the 1st post.

Thank you everyone for all the feedback and comments. [heart] I'm so glad this guide is already coming in handy for so many people.

• Changes in this version include:
  • Fixed typos and cleaned up language
  • Added a Table of Contents
  • Added page numbering
  • Cleaned up and consolidated information on a few of the initial pages
  • Added additional tools information, links to more YouTube videos and other helpful resources.

This is a fantastic guide! It helped me repair a board that I would otherwise have given up on.

Are you sure page 46 has the correct frequencies? On two fully working SE/30s, I measure exactly half the frequency listed for each ROM pin.

>> David Cook said:

This is a fantastic guide! It helped me repair a board that I would otherwise have given up on. Are you sure page 46 has the correct frequencies? On two fully working SE/30s, I measure exactly half the frequency listed for each ROM pin. Click to expand...

Thanks for the feedback! It's on the list for us to look into. (y)

>> Mac84 said:

Hello everyone, This has been a long time coming... presenting the Macintosh SE/30 Vertical & Horizontal Bars on Display "Simasima" Repair Guide !! View attachment 24299 This is a FREE downloadable PDF document (~55 MB) filled with high-resolution pictures and technical details. You can find this PDF file attached to this post. I can't take sole credit for this guide, many talented people and individuals contributed to this guide. This guide would not exist without the amazing efforts of the many geeky individuals in the vintage Macintosh and electronics community. While it would be impossible to name everyone individually, these fine folks know who they are. (and you can find some them mentioned in the guide!) This is an early release of this guide, consider it a beta release . There are some areas that are still a work in progress, refer to page 5 to learn more about that. So apologies if anything is missing, inaccurate or broken, but perfect is the enemy of good. As updates happen, they'll be logged at the end of this post. What's included in this guide: This comprehensive 112-page guide provides expert-level guidance on this common issue. Containing sections on: Theory of the issue Things to check first Troubleshooting & Repair Recommended Tools Clock signal references Resources and helpful links, including the redrawn schematics What's next? if you find this guide useful, have success stories related to it, feedback or corrections - please post them in this thread! Be mindful that not all replies can be addressed or reflected in the scope of this document. Since all future revisions of this guide will be attached to this first post, we kindly ask that instead of sharing the PDF to others, please share this link to ensure they always have the latest version. There are a number of things we'd like to add to this guide, but for now this makes a very solid first edition. Thanks again to EVERYONE who helped, this was a monster effort that took years to prepare and I'm super happy to post the initial version here for all to enjoy. -Steve Version history & notes: October 9, 2025: v0.9a Initial beta release ( archived ) October 25, 2025: v0.9b 2nd release (attached to this post) Changes: Fixed typos, added Table of Contents, added page numbers, cleaned up and consolidated pages, added additional tools information, added links to videos and other resources. Click to expand...

Working on two SE/30s now. This could be helpful. Thank you!

>> Mac84 said:

Hello everyone, This has been a long time coming... presenting the Macintosh SE/30 Vertical & Horizontal Bars on Display "Simasima" Repair Guide !! View attachment 24299 This is a FREE downloadable PDF document (~55 MB) filled with high-resolution pictures and technical details. You can find this PDF file attached to this post. I can't take sole credit for this guide, many talented people and individuals contributed to this guide. This guide would not exist without the amazing efforts of the many geeky individuals in the vintage Macintosh and electronics community. While it would be impossible to name everyone individually, these fine folks know who they are. (and you can find some them mentioned in the guide!) This is an early release of this guide, consider it a beta release . There are some areas that are still a work in progress, refer to page 5 to learn more about that. So apologies if anything is missing, inaccurate or broken, but perfect is the enemy of good. As updates happen, they'll be logged at the end of this post. What's included in this guide: This comprehensive 112-page guide provides expert-level guidance on this common issue. Containing sections on: Theory of the issue Things to check first Troubleshooting & Repair Recommended Tools Clock signal references Resources and helpful links, including the redrawn schematics What's next? if you find this guide useful, have success stories related to it, feedback or corrections - please post them in this thread! Be mindful that not all replies can be addressed or reflected in the scope of this document. Since all future revisions of this guide will be attached to this first post, we kindly ask that instead of sharing the PDF to others, please share this link to ensure they always have the latest version. There are a number of things we'd like to add to this guide, but for now this makes a very solid first edition. Thanks again to EVERYONE who helped, this was a monster effort that took years to prepare and I'm super happy to post the initial version here for all to enjoy. -Steve Version history & notes: October 9, 2025: v0.9a Initial beta release ( archived ) October 25, 2025: v0.9b 2nd release (attached to this post) Changes: Fixed typos, added Table of Contents, added page numbers, cleaned up and consolidated pages, added additional tools information, added links to videos and other resources. Click to expand...

Thank you very much for your helpful information.

This guide was the reason I found this site and joined, well done and thank you for this!

I wanted to ask about the Reset section, on page 44, it instructs that UB11 Pin6 should go to 0V.

The picture is showing UB10 highlighted on my logic board, instead of UB11 - I can't get UB10 or UB11 Pin6 to drop below 3.9V with the S1 button pressed.



Can anyone confirm that Pin6 VSNS, should also be at 0V with the S1 button pressed.


Thanks again!

With power off, check the continuity of S1 when pressed and not pressed. This switch often fails due to capacitor juice. I've replaced several.

You should still check S1 (to make sure it isn't shorted). However, given the resistors (100/(100+27))*5V = 3.94V, the voltage when pressed should be about 3.9V volts.

What are you getting for pin 5 of UB11 and pin 5 of UB10 when the button is pressed and released?