General Category > Lisa Troubleshooting and Repair

Recent Lisa acquisition and repair - really bad NiCad leak.

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rayarachelian:
So since there was a recent thread on 68kmla about trying to transfer BLU images to LisaEm, I took this Lisa out and one of my ProFiles and an old dell E6500 laptop, I've upgraded to Ubuntu 20.04 and installed minicom on and tried to image it as I wanted to make some BLU images to play around with, and also since I haven't powered on any of my ProFile drives in at least 4 years and got worried that the lubricant would freeze.

This Lisa's not doing so good. I mentioned that the display is bleeding and it gets worse with time. By the end the display turned off and tweaking the brightness showed just a white screen with diagonal scan line reflections. I used a 1.8A known good power supply from another Lisa, so it must be the video board in addition to the I/O board.

I also saw all sorts of issues such as COP failures on the I/O board turning the Lisa on as soon as power was applied, random beeping, moving the mouse causing the COP to interpret mouse movement as keystrokes, and all sorts of other fun. I wasn't able to transfer the Profile it all.

If I remember correctly I had swapped out the I/O board with a spare, so this one is now bad too, and had swapped the motherboard too since the original one was corroded. But this spare was also from a Lisa that had leaky NiCads... so more work to do...

There was a very tiny bit of good news in that when I first plugged it in, I heard the 30M SunRem hard drive spin up, which when I put this Lisa away had stopped. I didn't want that to happen, but I'm glad it's still alive. But there's probably some capacitor issues there since it started somewhat working after an extended period of being left alone (almost a year now!)

I'm going to try to take another BLU image tonight, and I got the top lid unscrewed so I can get to the video board and catalog the capacitors. I think I should start creating Lisa capacitor spreadsheets as part of this. I'll start with this. Last time I fixed my power supplies, I sort of had a shopping list, but... I think I need a better way to track this.

snuci:
Hi Ray,

When I cleaned my badly corroded I/O board (and other boards), I used an Ultrasonic cleaner with 50% vinegar and 50% water and do this for about 50 minutes.  The traces where the corrosion was turned black but you could use a fiber pen to clean the black stuff off and you would get the copper traces underneath is some cases.  Note: I did have a couple of components fall off :)

Pictures of before:



Ultrasonic cleaner I use:


After:

rayarachelian:
Is it this guy? https://www.amazon.com/VEVOR-Commercial-Ultrasonic-Capacity-Solution/dp/B01HGNYO0U/ 6L?

Fall off you say? I remember an old joke about a guy who gets his willy infected and the doctor wants to chop it off, so he goes to another one and another and they all say the same thing, then he gets to the last one, and the doctor goes "Cut, cut cut, that's all these butchers know how to do. Just give it a week and it will fall off by all by itself." :-D

snuci:

--- Quote from: rayarachelian on May 18, 2020, 02:36:01 pm ---Is it this guy? https://www.amazon.com/VEVOR-Commercial-Ultrasonic-Capacity-Solution/dp/B01HGNYO0U/ 6L?

--- End quote ---

Mine is also 6L and heated but it is probably a different manufacturer but that ought to do it.  I hadn't heard of anyone trying this before on a PCB let alone a Lisa I/O board so if you do decide to go this route, you can always do other boards you have that may have had corrosion just to make sure it is all off.  I was pretty amazed.  Good luck!

patrick:
Ultrasonic cleaning is fine for PCBs. However, you should remove crystals and ceramic cavity packages like EPROMs -- these might crack.

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