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Trying to coax a “clean” SE/30 to life…
Posted by: CYB3RBYTE on 2022-11-21 08:04:43
Hey all,

I finally acquired one of my white whales, a non-battery bombed SE/30. Upon getting it open and running, it would chime, albeit very softly, and if you pressed the reset button, would instantly error out to a sad Mac message, as shown below:

33574678-2152-4802-A3F2-953B93413CAA.jpeg

It of course had some capacitor leakage, so I replaced all the caps on the analog board, Sony CR-44 power supply, and the logic board. I first removed the old SMD electrolytics on the logic board, then scrubed it with 91% IPA and left it to soak overnight. Then dryed it in the morning, continued with recapping and inspecting the board.

7170CEC4-85E6-44B4-8582-8A37D9A9D5A8.jpeg


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Posted by: CYB3RBYTE on 2022-11-21 10:10:15
Ran out of time when editing the last post, but regardless, this error screen does not let up. I’ve replaced the RAM with 4 known good modules, cleaned and reseated the ROM, etc. If I disconnect all SCSI devices and insert a floppy (it has a known good drive which I disassembled and lubed) it will very briefly show a happy Mac, but then it ejects the disk.

It will not boot off a hard drive, as when one is connected, it will not get to the flashing folder because it is probably seeing a SCSI device, but will not start the rest of the boot chain. I connected a blueSCSI externally and get nothing from it’s indicator LEDs other than three flashing lights in a row.

Any ideas what‘s keeping it from booting up / causing the immediate reset error? Thanks!
Posted by: unity on 2022-11-21 15:39:03
I think that is a software error. Disconnect the internal drive and boot from a floppy incase the SCSI chain is an issue. And I will add, it will need a recap. So dont bang your head too hard getting it going, it may never until you recap. Although that is a very clean board, so it will be easy work.
Posted by: CYB3RBYTE on 2022-11-21 17:36:36
I think that is a software error. Disconnect the internal drive and boot from a floppy incase the SCSI chain is an issue. And I will add, it will need a recap. So dont bang your head too hard getting it going, it may never until you recap. Although that is a very clean board, so it will be easy work.
Interesting. I recapped it with solid tantalums before posting, should have made that more clear. I was talking to someone and they mentioned perhaps the corrosion around the audio chips is causing issues with other VIAs in that area?
Posted by: croissantking on 2022-11-22 00:34:24
Have you tried other RAM? Also, the ROM SIMM may not be making good contact.
Posted by: bibilit on 2022-11-22 01:57:32
The F code is an exception code, probably not related with Ram or Rom.

Hard to troubleshoot
Posted by: croissantking on 2022-11-22 02:13:33
The F code is an exception code, probably not related with Ram or Rom.

Hard to troubleshoot
What would it be related with?
OP should check for corrosion. Could be a marginal trace somewhere?
Posted by: bibilit on 2022-11-22 02:28:59
What would it be related with

hard to say, no way to know for sure
Posted by: croissantking on 2022-11-22 02:39:18
hard to say, no way to know for sure
Lol, that’s uplifting for the OP 🙄
Posted by: croissantking on 2022-11-22 02:49:28
Interesting. I recapped it with solid tantalums before posting, should have made that more clear. I was talking to someone and they mentioned perhaps the corrosion around the audio chips is causing issues with other VIAs in that area?
I would check the board very carefully for any signs of corrosion or anything else that looks not quite right. If you wanted to upload some hi-res photos of your board then we could have a look too.

As has been mentioned it could be anything but in order to troubleshoot you have to be systematic and narrow down the possible causes.

Also, I noticed some junk on screen above the sad Mac icon. This might be a clue.
Posted by: CYB3RBYTE on 2022-11-22 14:13:13
Thanks for the help so far everyone. Yes, I have changed RAM simms to known good ones I took out of my working SE with no change. I’m ordering specific RAM for this machine anyways just in case it is that picky.

As for corrosion, yes there was originally corrosion around the audio chips prior to the board being recapped. I let it soak in 91% alcohol overnight and scrubbed it well with a ESD brush (including RAM and ROM slots) but perhaps this didn’t get everything. Perhaps it would be good for me to try vingear next.

I’ve used this diagram below to check the VIAs and connections in the sound chip area with my Hantek scope / MM, and so far everything has continuity. Any idea where any more of these schematics exist so I can test more of the board?

CFE9229A-64F8-4B71-951F-0B7F51CEB561.jpeg
Posted by: CYB3RBYTE on 2022-11-28 14:47:47
After dipping the board in vinegar overnight, and letting it air dry for 5 days (plus using compressed air), there’s no change in behavior when booting. Here are some close-ups of the board. It now will only turn on and display the cursor for a brief moment (and a happy Mac if a known good HD is connected), then video cuts out and I hear a clicking from the analog board area (which is known good).

Here are the close ups of the board, I’ll include a link to a video of what it’s currently doing.


EA46BE5B-2719-43F6-96FF-AAAA1B4F397A.jpeg
8CBADAB3-CC9C-47C6-9E09-B2502B0F9786.jpeg
1BD80E12-5407-468C-8C8B-2E6EBBB18D4B.jpeg
C07A0FFC-B8DF-4409-BBD7-2EB6D9765AC9.jpeg
218C7851-B8FF-430A-86B1-3433345B35F2.jpeg
1368823F-75CA-4844-8A15-E85E27C7F7F0.jpeg
87DE3DFB-50E3-40B5-88F8-B87E3543E5A4.jpeg
C9707878-6A9F-491A-B91F-9F8484416BFE.jpeg
6C0DD6B3-530B-4A7D-A522-6C7485CBC9C9.jpeg
FDDCB489-5881-4666-8DA2-2AE2526E05D9.jpeg
Posted by: imactheknife on 2022-11-28 18:54:39
Well, for one vinegar in my opinion is good for cleaning and rinsing right away afters over night might be pretty harsh on solder joints, but someone else can confirm that. I use isopropyl and scrub then sit for a few hours. Rinse with distilled water, let dry..
Posted by: imactheknife on 2022-11-28 18:55:29
Well, for one vinegar in my opinion is good for cleaning and rinsing right away afters over night might be pretty harsh on solder joints, but someone else can confirm that. I use isopropyl and scrub then sit for a few hours. Rinse with distilled water, let dry..
Where is the link
Posted by: CYB3RBYTE on 2022-11-28 18:56:29
Where is the link
Posted by: CYB3RBYTE on 2022-11-30 07:33:15
So at this point, after testing all the VIAs near the audio chips, I'm really considering sending the board to someone to get it diagnosed / fixed. I'd love any recommendations that you all have. Thanks!
Posted by: CYB3RBYTE on 2023-01-10 18:02:38
I had Thomas from Amiga of Rochester service the board, and the most random failure occurred: the crystal oscillator! No wonder it wouldn't get far in the boot process.

He repaired several bad cap solder pads that I damaged during my recap attempt (oops) and now the machine is running great! I have installed a SCSI2SD v5.2 I had lying around, 16MB of RAM, and a GGLABS 512kb ROM SIMM for 32-bit clean ROM. I can't wait to show this machine off and redrobright the case in summer.
Posted by: LaPorta on 2023-01-10 19:59:21
What a great story in the end!
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