Prototype PowerBook 550 advice

[Durosity]

So I’ve managed to pick up what seems to be a Prototype PowerBook 550. The screen doesn’t work, and it doesn’t have the original 68040 processor (it’s been upgraded to a 167mhz 603), but other than that it’s working.

Now the weird thing about this 550 is that it isn’t black like the retail models. It’s the same grey as the 520/540 models. Never seen one of these before. The lower case is just stock 500 series with the usual texture, but the screen assembly is the typical untextured indicative of a prototype, and also has some odd markings where symbols would usually be:






What I want to do is open the screen assembly to check out the panel that’s in it and see if it’s that or maybe the ribbon cable that’s broken. However I don’t want to break the connector cover at the bottom that has somehow managed to remain intact, despite the fact that even when new they’d snap off if someone sneezed near the machine!

Any advice on best way to remove it without causing damage?

 

[Durosity]

It occurs to me this is a stupid place to have put this thread.. can mods move it to the appropriate forum?

 

[Daniël]

Not too surprised it's still PowerBook 520/540 grey, I always assumed the 550c was black due to the fact Apple stopped producing the 500 series before the one-off 550c Japan launch, meaning they weren't producing plastics with that coloring (would have probably been expensive to continue to produce for such a one-off), and resorting to just using the new black colored plastics for the PowerBook 5300 series. During the prototype phase, they hadn't yet canned the 500 series, I would assume.

EDIT: The fact that it's been PowerPC upgraded is a bit of a shame, given the scarcity of "full-fat" 68040 CPU cards for the PowerBook 500 series, but it's also highly amusing to me that a prototype was seemingly used as someone's personal machine.

 

[Durosity]

I suspect this may be an earlier prototype before the decided to make it black. But that’s just conjecture.

Also.. as the lower section is just that of a 540 it may well have just had a 68LC040. I guess we’ll never know!

And yeah it certainly was used as someone’s machine.. it’s full of software and documents, which I will check for any software that may be of use then wipe it

 

[3lectr1cPPC]

You can try blasting the clutch cover with a hair dryer before you try to get it off, that could help to soften the plastic enough that it might not break.
Getting one off without breaking the clips isn't impossible though, I managed it on my 540. One set of clips was broke but they already were before I removed it.
Also - would you mind if I used your images of this thing on MacDat?

 

[croissantking]

it doesn’t have the original 68040 processor (it’s been upgraded to a 167mhz 603)

On paper this sounds amazing, but we all know the full 040 is more coveted.

 

[Durosity]

You can try blasting the clutch cover with a hair dryer before you try to get it off, that could help to soften the plastic enough that it might not break.
Getting one off without breaking the clips isn't impossible though, I managed it on my 540. One set of clips was broke but they already were before I removed it.
Also - would you mind if I used your images of this thing on MacDat?

Yeah that’s a good idea.

And yes of course. I’ll send some pics when I take the screen apart!

On paper this sounds amazing, but we all know the full 040 is more coveted.

It is! But.. I am hoping to still get a full 550c with the original processor!

 

[Durosity]

I’ve been able to successfully dismantle the screen of this machine. Interestingly I’m not the first person in here, but then being a prototype that’s hardly surprising. Here’s what I found:

Markings on the inside of the case:




Inverter:

Inverter ribbon

Screen:
View attachment IMG_2365.jpeg

 

[3lectr1cPPC]

What’s the LCD part number? Same as production 550cs?

 

[Durosity]

Controller board:



A quick search for the part numbers SHARP LQ045 and SHARP X1340KA doesn’t come up with anything.

I’m debating next steps. Ideally I want to try and get the screen working, and it’d seem the next logical step is to recap the screen itself, but.. is it sacrilegious to replace parts of a sample unit?

 

[Durosity]

What’s the LCD part number? Same as production 550cs?

Not sure, I’ve not yet had a look at a 550c teardown to compare the parts. Would be interesting to see if anyone has a good link for one as I’m too exhausted right now. It’s been a long day!

 

[jmacz]

Both the inverter board and the control board look different than anything I've seen so far in 540c's or 520c's. And that LCD display's caps also look different from the Sharp display my 540c has.

 

[3lectr1cPPC]

I do have cap reference with images for the 550c up on my website: https://macdat.net/cap_reference/apple/powerbook/550c.html
(Thanks to AEChadwick).
The production units used Sharp LQ10D32A displays.
The inverter board production 550cs use is the same as the one the 190/5300 series uses.

I'll also link my PowerBook LCD Index here for future reference, it has part numbers for most of the PowerBook displays.

PowerBook LCD Index - MacDat

macdat.net

 

[jmacz]

The inverter board production 550cs use is the same as the one the 190/5300 series uses.

Ah yes, you're right.

 

[croissantking]

and it’d seem the next logical step is to recap the screen itself, but.. is it sacrilegious to replace parts of a sample unit?

I think it’s more than OK to recap it personally as you are looking after a piece of history. Maybe stick to tin cans (so electrolytic, or polymer) for the correct aesthetic.

 

[Performa450]

Controller board:
View attachment 68976
View attachment 68977

A quick search for the part numbers SHARP LQ045 and SHARP X1340KA doesn’t come up with anything.

I’m debating next steps. Ideally I want to try and get the screen working, and it’d seem the next logical step is to recap the screen itself, but.. is it sacrilegious to replace parts of a sample unit?

I like the EVT serial # on that!

 

[Durosity]

Thanks for all the input from everyone above…

Good news.. it’s now working!


Kinda. It still occasionally glitches. I think it’s also partially due to the ribbon cable that goes from the board under the Apple logo to the LCD itself.

But at least I know it’s worth trying to save! And the screen looks really nice and bright too!

 

[croissantking]

Kinda. It still occasionally glitches. I think it’s also partially due to the ribbon cable that goes from the board under the Apple logo to the LCD itself.

But at least I know it’s worth trying to save! And the screen looks really nice and bright too!

Nice, how did you get it working? A specific fix (like a recap) or just playing around?

Is the LCD the same as the one found in the 5300c? Or is it just the inverter board that's the same?

 

[joshc]

Thanks for all the input from everyone above…

Good news.. it’s now working!

View attachment 69097
Kinda. It still occasionally glitches. I think it’s also partially due to the ribbon cable that goes from the board under the Apple logo to the LCD itself.

But at least I know it’s worth trying to save! And the screen looks really nice and bright too!

Two aliases to internet explorer 3 right next to each other, so you definitely CAN get on the Internet there without any confusion.

 

[3lectr1cPPC]

Issue looked just like a loose display cable, I've seen stuff like that before so that would be my guess. @imactheknife - you should dump the contents of the hard drive!

LCD MAY be compatible between them. 550c is Sharp LQ10D32A. The 5300c used either a Toshiba, Sharp, or maybe also a Hosiden LCD, and all three use different cables. However, the 5300c Sharp LCD is an Sharp LQ10D32M. So they're very similar part numbers. May be compatible, may not be. I don't think anyone's tried it yet.