LisaList2

Advanced search  

News:

2019.06.07 fixed NChat for the "Curve" theme, will eventually move it to its own page and add it to the default theme as well. Other plugins are next. see post in the Meta board for details

Pages: [1]   Go Down

Author Topic: Recent Lisa acquisition and repair - really bad NiCad leak.  (Read 794 times)

rayarachelian

  • Administrator
  • Sr. Member
  • *****
  • Karma: +7/-0
  • Offline Offline
  • Posts: 143
  • "But what's puzzling you is the nature of my game"
    • LisaEm
Recent Lisa acquisition and repair - really bad NiCad leak.
« on: March 16, 2019, 06:09:58 pm »

I recently picked up another Lisa, this makes it four.
This one is an XL. It has the 800K Sony drive and I/O ROM, and Sun Rem hard drive inside that self-identifies as a Profile, but uses a ST-138 (which is a 30MB drive?). The drive is connected from the external motherboard parallel port via ribbon cable snaked back internally from the back to the drive cage.BLU identifies the drive as having f1b8 blocks or 61880 blocks, or 30940K, so it's a 30MB disk. Block size shows up 0x214 (512 + 20), revision as 390 spares as 0x20 (32), 0 spares allocated, 0 bad blocks.

What's interesting is that the drive shows up as PROFILE (but not PROFILE-30!) so perhaps I can manage to get LOS on it if I swap out the ROMs with H ones, not sure, unless the ProFile driver hard codes the size of the disk or has other limits, that might be an interesting thing to try. If it works, or if I can find where in the driver such limits exist, it would mean that we can get larger disks in LisaEm.

The drive isn't bootable unfortunately, it shows a single line of text saying "LOADING." and then shows more ...'s like "LOADING......" and eventually goes back to the boot ROM without starting up. Likely it has some version of MacWorks on it, but got damaged. Perhaps I can clone it with BLU and see what's there.

I wasn't able to boot NeoWidex as it got a disk error 47 after reading about 65K or so, so I'll need to dig up a floppy cleaning disk and some isopropyl alcohol, or will need to take the drive apart and use q-tips, etc. But BLU booted up fine.

The Video display also bleeds to the right, that is if there's a vertical line on the display, it smears to the right of that line, such as from the hourglass icon or text or the border of windows, so either the video board or the power supply I used needs a bit of work as well.

Some lessons about this Lisa.
1. The floppy cable was connected backwards into the LisaLite adapter, when this happens, the power light will light up for about half a second, but will go out before you let go of the button - so that's something to add to the LisaFAQ. This is different from the tick-tick-tick of a bad power supply.

2. There is corrosion not just on the I/O board but also on the CPU board and mostly ABOVE the batteries! Infact I wasn't able to get video out of it with its original CPU board at all, and had to use a spare.
There is a pin messed up on the I/O board connector of the motherboard, but it seems not to affect it - or maybe it does and I haven't noticed it, or is causing the floppy issues, not sure yet.
Other than this damage, this Lisa looks impressively clean and only slightly yellowed. I don't actually think it was cleaned. I suspect it wasn't used very much, and perhaps stored in a sealed environment, which then concentrated the corrosive gas from the NiCAD pack.
The back of the CPU board had some of this crud crystallized into weird patterns, but it was like a film of dust.

Besides the corrosion on the I/O boards and CPU board, the boards inside were very clean, the memory boards were pristine.

But the lesson here is that the NiCAD's don't just leak alkaline fluid, but also offgas corrosive gas which then damages other things. I found some slight corrosion on the inside corners of the case on the steel casing itself, and even some stuff on the outside of the CRT - now that might just be regular dirt, I don't know, but as it had the nylon screen protector and the dirt was between the nylon and the CRT, I'm kinda thinking maybe it is the stuff from the battery after all!
Incase you're wondering, I used a high power electric air blower meant to replace compressed air to clean the cruft off the boards. Next, I soaked a paper towel with some distilled white vinegar and RO filter water (not as good as distilled, but close enough) and wiped both the I/O and CPU board thoroughly and then used an antistatic electronics cleaning brush to scrub (it's much like a toothbrush but bigger).
I then used WD40 Electronics Contact Cleaner spray (no this is not regular WD40, do not use that!), and gave both boards a generous spraying on both sides until they were dripping with it, and then left them to offgas the alcohol and whatever else overnight in the garage.

That spray is very strong and gave me a bit of a headache even though I did that outside the house, so take that into consideration before using it. It did clean the boards, but looks like there's still a lot of corrosion on the solder points and on some legs of various ICs. Likely I'll have to reflow the solder on these and check for broken traces, but weirdly there's more damage on the CPU board than on the I/O board. Most of the damage is ABOVE the batteries, only a little is below. This is why I say these batteries offgas.
« Last Edit: March 16, 2019, 07:31:32 pm by rayarachelian »
Logged
Fate whispers to the warrior, 'You can not withstand the storm.'  The warrior whispers back, 'I am the storm.'

rayarachelian

  • Administrator
  • Sr. Member
  • *****
  • Karma: +7/-0
  • Offline Offline
  • Posts: 143
  • "But what's puzzling you is the nature of my game"
    • LisaEm
Re: Recent Lisa acquisition and repair - really bad NiCad leak.
« Reply #1 on: March 16, 2019, 07:32:06 pm »

photos 2
Logged
Fate whispers to the warrior, 'You can not withstand the storm.'  The warrior whispers back, 'I am the storm.'

rayarachelian

  • Administrator
  • Sr. Member
  • *****
  • Karma: +7/-0
  • Offline Offline
  • Posts: 143
  • "But what's puzzling you is the nature of my game"
    • LisaEm
Re: Recent Lisa acquisition and repair - really bad NiCad leak.
« Reply #2 on: March 16, 2019, 07:34:29 pm »

photos 3
Logged
Fate whispers to the warrior, 'You can not withstand the storm.'  The warrior whispers back, 'I am the storm.'

rayarachelian

  • Administrator
  • Sr. Member
  • *****
  • Karma: +7/-0
  • Offline Offline
  • Posts: 143
  • "But what's puzzling you is the nature of my game"
    • LisaEm
Re: Recent Lisa acquisition and repair - really bad NiCad leak.
« Reply #3 on: March 16, 2019, 07:36:02 pm »

corroded cpu board front
Logged
Fate whispers to the warrior, 'You can not withstand the storm.'  The warrior whispers back, 'I am the storm.'

rayarachelian

  • Administrator
  • Sr. Member
  • *****
  • Karma: +7/-0
  • Offline Offline
  • Posts: 143
  • "But what's puzzling you is the nature of my game"
    • LisaEm
Re: Recent Lisa acquisition and repair - really bad NiCad leak.
« Reply #4 on: March 29, 2019, 03:21:59 pm »

This 5 video youtube list: https://www.youtube.com/watch?v=OQIWmmxifow&list=PLOkflnR85gThmBTDaI1hAmYPGSeYlayys&index=1 is relevant to this discussion though you don't see the actual repairs in action.

These two links are useful as well:BTW, The fiber glass pens should be used with care and masks as you don't want to breathe that stuff in.
I'll wait for a warmer sunny, day and do that bit outside on the deck while wearing a facemask.
Logged
Fate whispers to the warrior, 'You can not withstand the storm.'  The warrior whispers back, 'I am the storm.'

jamesdenton

  • Full Member
  • ***
  • Karma: +20/-0
  • Offline Offline
  • Posts: 27
  • ArcaneByte
    • ArcaneByte
Re: Recent Lisa acquisition and repair - really bad NiCad leak.
« Reply #5 on: May 07, 2019, 09:34:55 pm »

Good luck in your resurrection attempts. Thanks for sharing!
Logged
Pages: [1]   Go Up