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SE/30 logic board is just dead
Posted by: mraroid on 2019-01-03 13:50:30
The logic board is recapped and cleaned in the ultrasonic cleaner
Were you able to find a ultrasonic cleaner that was big enought to put the entire board in at one time? What is the name and model number of the one you used?  I have a small one from Harbor Freight and need a new one. Thanks.

mraroid
Posted by: NE555 on 2019-01-03 14:58:05
Were you able to find a ultrasonic cleaner that was big enought to put the entire board in at one time? What is the name and model number of the one you used?  I have a small one from Harbor Freight and need a new one. Thanks.

mraroid
The one I have is from crest. It holds 3.25 gallon of fluid and costs $1150. Not sure if that is the kind of money you are looking to spend
Posted by: NE555 on 2019-01-03 16:23:49
So as I said, I didn't have a connection from C2 to UB10 or UB11 on the 12v line. Once I connected it I get a simasimac with normal chime That means there is a non connection to the ROM, correct? or was it the RAM? or both?

IMG_4628.JPG
Posted by: NE555 on 2019-01-03 20:50:04
I noticed that the 5 PAL chips get pretty warm. No other chips do.
Edit; Replaced the Video ROM and all is good now
Posted by: AwkwardPotato on 2019-01-03 20:56:38
Correct me if I'm wrong, but I'm almost certain that if you're getting a normal startup chime, the connections to the ROM and RAM are good. Maybe it's a VRAM issue?
Posted by: NE555 on 2019-01-03 21:06:03
Happy Ending 

IMG_4630.JPG
Posted by: NE555 on 2019-01-03 21:07:28
Correct me if I'm wrong, but I'm almost certain that if you're getting a normal startup chime, the connections to the ROM and RAM are good. Maybe it's a VRAM issue?
see my post above yours
Posted by: AwkwardPotato on 2019-01-03 21:10:12
Ah, I see. Nice job getting it running!
Posted by: superjer2000 on 2019-01-03 21:25:00
I noticed that the 5 PAL chips get pretty warm. No other chips do.
Edit; Replaced the Video ROM and all is good now
Congrats on a successful repair. One question:

What chip(s) did you replace to replace the video ROM?  Was it the VRAM?

Thanks!
Posted by: NE555 on 2019-01-04 08:31:45
So here is what I have done.
I first took off the Sound chips and cleaned underneath them and checked the traces beneath the chips. Then I installed some double wipe sockets.

After that I reconnected the 12v+ to the sound chips from C2. I coated the spaghetti wire with conformal coating to epoxy the wire to the substrate.

And finally replaced the Video ROM.

Next is a final ultrasound clean and it's a done deal. SE/30 made happy again.

IMG_4632.JPG

IMG_4631.JPG

IMG_4634.JPG
Posted by: superjer2000 on 2019-01-05 10:35:40
What "Video ROM" chip did you replace?
Posted by: NE555 on 2019-01-05 10:51:32
What "Video ROM" chip did you replace?
There is only one Video ROM or VROM, as it's sometimes called. 
you can see it in the picture of the Logic Board I have posted in my last post. It's the chip next to the Silk screen label , which reads 'Video ROM'
That's how I found it first, anyway.
Posted by: AwkwardPotato on 2019-01-05 12:50:09
The conformal coating over the patch wire looks pretty neat and tidy. I'm definitely trying that out the next time I have to run a jumper.  🙂

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