68kMLA Classic Interface

This is a version of the 68kMLA forums for viewing on your favorite old mac. Visitors on modern platforms may prefer the main site.

Click here to select a new forum.
Powerbook 100 extreme screen repair
Posted by: Cedsrepairs on 2021-10-05 03:32:44
Hey, just wanted to share how proud I am of my "extreme" repair. 😎


ced_2021-10-04@21h47_IMG_5253.JPG

This PB100 screen has a problem I don't really understand.

At first I thought I caused it, but the more I looked at it, it seems I did not.

I got the PB100 is a sorry state ( yellowed, stuck hard disk heads, needed a complete recap , and... screen was you see it )

The problem is that the opaque paper just behind the backlight has somehow "melted" on top of the LCD glass.

ced_2021-10-05@10h16_IMG_5257.JPGced_2021-10-05@10h21_IMG_5259.JPG

ced_2021-10-05@10h21_IMG_5259.JPG

This was a difficult repair as that thing really melted on top of the glass for whatever reason

I cleaned that residue with Acetone (after carefully testing) then quickly wiped with IPA.

I then created a new silk screen out of translucent paper I found in my daughter's school stuff. 🤣

ced_2021-10-05@11h32_IMG_5271.JPG

That's the original paper there, with the horrible stain/melted zone. And the cut I did to replace it.

And here's the result

Paint_Shop_Pro_XJt4FOtoQg.png
(ignore the white balance which differs - the screen color is the same as it was)

I can live with the 30 or so dead/red pixels in the middle - due to impact of the trackball ( thanks @desertrout for the explanation )

Just shared this in the hope this helps someone in the future.
Posted by: desertrout on 2021-10-05 09:59:44
Nice work! I guess you can move the 100 up from the 'Current Projects' line to the 'Restored / Working' line in your signature. 😉

PS - that paper is the diffuser, and you can get replacement sheets pretty inexpensively (https://www.bhphotovideo.com/c/prod...02302162124_E_Colour_216_White_Diffusion.html), but the paper seems to be working well enough. 👍
Posted by: Cedsrepairs on 2021-10-05 10:08:16
I’m still waiting for a scsi2sd which will be a bluescsi ; I’m importing there in Europe ; the package just got delivered to the company that will send it back to me

when I see a pb100 with a better screen I’ll probably swap
Posted by: desertrout on 2021-10-05 10:11:24
Nice. BlueSCSI is fantastic!
Posted by: Byrd on 2021-10-05 17:55:13
Nice work - to prevent further LCD leakage (the pink blotch), put some rubber feet/spacers between the LCD and the palmrest - the existing rubber bumpers wear down in height/degrade over time, pushing the trackball into the LCD which causes small micro fractures on the LCD panel and further damage. Your damage is minimal - I've come across half a dozen PB100's in the past few years which had much broader damage around the trackball site.
Posted by: Cedsrepairs on 2021-10-06 00:05:57
Thanks @Byrd !
this unit is really back from the dead ( nothing was working when I got it ; even the power brick is dead ) and it’s nice to see it start.

The recapping was relatively easy once you have the right components ( it took me 3 orders to get the sizes right ) but the recapping of the screen is difficult (imho)

the hard disk is still stuck ; I unstuck it manually but I think it just sticks back ; I may need to add tape or something . I’ve seen that on a video but my conner drive doesn’t look like it’s built the same as the one of the video ( the part where the guy puts tape on cannot be removed on my hard disk )

ill probably repair the powerbrick while waiting for the bluescsi to be imported in Belgium 🙂
It’s probably - again - leaky caps . It currently outputs zero volts .
Posted by: cheesestraws on 2021-10-06 02:29:19
What a nice result. Well done.
Posted by: desertrout on 2021-10-06 13:32:28
re: PSU recapping - there are some good threads here on that procedure, a quick search should bring them up.
1