Having taken the leap from desktop (compacts as well the various II series and quadras), the laptops are in no way like the desktops in terms of reliability. I have a fully restored 540c and 5300c. But I have to really baby them, constantly worried about the screens (the 5300c just started...
I don’t have any info to share as I don’t own the hyperdrive but asking out of pure curiosity, did the rom image allow you to restore the second drive you picked up? Is that one working now?
There is a latch under the closest corner in that picture. It’s built into the
plastic floppy/hard drive bracket. It’s on the half circle thing on the bracket. It holds the corner of the PSU closest to the half circle. You push it in towards the floppy/front of the case. There is nothing else...
I've just been using a sharp x-acto knife and just cutting along the seems over and over again until it starts spreading. That way there's minimum loss of material so I can close it up again, vs a dremel which will cut up a lot of material.
My EMM chip had a short on one of the pins (confirmed with chip removed) so something definitely seemed wrong with it. It did not have any physical damage, or visible corrosion. Could have been ESD although I was grounded and took precautions. Mine didn't exhibit as flakiness. It was dead.
Congrats!! I was only 2 for 3 on mine.. the one that failed has a bad Apple EMM chip. It's pretty awesome having these working batteries as it makes the PowerBook's that much more enjoyable. Mine have held up for months now. I assume you already fixed the PRAM battery too?
Hmm, interesting. Does look simpler/more crude. My two programmers don't look like they support that chip. Would be great if it can be copied opening the door to some clones.
Just curious, which transistor went bad for you?
I had an issue with the one pointed at by the blue arrow on one of my batteries and had to replace it. (Ignore the other arrows, I am re-using a previous picture).
Mine wasn't physically broken like yours (or maybe it was, I just wasn't...
Nice, progress! How did you get it to detect? What was wrong?
For the uncorrectable errors, some folks said you need to keep trying a few times. For me, after 10 attempts, I gave up. It looked like the errors were in the stored data in the battery so I decided to replace the Atmel 93C66 memory...
It has two mini din 8 ports but they are full 8 pin and I thought those were for serial connections. It doesn't have the usual ADB mini din 8 size ports with 4 pins. I think it was Sound Box peripheral that had the ADB port on it? I think there were some DIY adapters that were made so need to...
Also no corrosion on the internal spring loaded contacts?
Oh and was the one SMD cap on the main board near the spring loaded contacts replaced? I think someone mentioned it might be involved with the battery functions.
Hmm, so ruling out some obvious ones:
All four ribbon wires are connected? The EMM board takes two grounds, one vcc, and the two inner ones used to talk to the laptop.
The continuity is there from the external pads (on the case) to the emm board?
You are seeing power get to the EMM chip with...
A few more items...
Thanks to a tip from @History_SE30_Dude, picked up two SCSI drives off Craigslist primarily for the enclosures. Should make it easier to test SCSI drives going forward. They came with working drives but way too large for my 68K Macs.
And yes.. another SE...
Got it...
Sending one working and one failed Spectrum 24/III accelerator boards to @Bolle for reverse engineering. Hopefully he'll be able to get around the security fuse set on the GALs. 🤞 In which case I will have two fully functional copies of this particular video card to add to my growing SuperMac...