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You could try fixing the pin, it would be difficult to swap the entire socket without doing reflow soldering with solder paste, but that's also possible.

Yup I have one of these! I have to fix the backlight but it does work :-)

That's rad and very promizing!

So I wend deep into the details on how voltages are generated and learned a few things. - The main +5V is generated using a MOSFET and a feedback loop with an op amp to drive the gate with a PWM signal. This can go wrong and is the reason why I'm seeing the hiccups on the power supply. When...

Unplug the hard disk, and dial current down to 400-500mA. It should power when you press the keyboard and display the floppy icon. Pretty much all the portables I have seen (well, 3 so far) have had supper finicky power supplies, but with the 5V hardwired like that it powers on rock solid. So it...

I have one here to work on. You can tie +5V to the heatsink of Q16 and ground to the battery ground. Make sure you have a regulated power supply, and set current limiting to make sure that nothing release the magic smoke. Note that this will power the entire +5V rail but not some other rails...

It could fit in 1/4th the footprint, so certainly in the volume of the module. It could also bypass some of the old power components and capacitors that are around the module.

I do know, but it is a 1:1 replica of the original module using the same hard to source components and precision resistors... not to undermine the immense effort of the task, it seems the hybrid just generate +5V and -5V, as well as a couple control signal for the PMU.

The hybrid module pretty much deal will all the voltage rail generation on the motherboard, with power sources coming from both the power adapter, and the battery. It uses some external components, a couple MOSFETs that are around it, and a LT1070 to generate the +12V rail. 1989 vintage DC/DC...

I have to look at the schematics in more details but I don't think it does.

Big question, as I currently have a Macintosh Portable from a friend that is suffering from a bad hybrid (it has taken a toll of some chips in the audio section, and the 5V rail is looking absolutely horrible with spikes up to VBAT). It seems the hybrid does not do much, other than generating...

Well it was a good plan to add the DIP switches then! Did not thought of the impossibility to use software PLL settings in specific cases.

Oh no way! I'll check that! All the vias are tented under the BGA and under the PGA, otherwise. Edit: I checked that little solder blob and it did not make connection to anything, took it off.

It does, I did put 256MB in mine. It's absolutely useless and makes it very slow to boot, but it works! :D

I honestly though no one would try because the board is exceedingly rare, and also it's a very difficult project. It took me two full month to sand down the PCB and retrace it all, and make verifications. Getting the 8 layer PCB manufactured also took a long time. Ultimately there was the...

I'm afraid I have missed the thread, but I have already made a replica of the PowerLogix 750GL accelerator... It however does not work as I did blow the VRM, so there's possibly a short somewhere in my design that I need to trace. I had a PowerLogix board that I recovered from a scrap lot, that...

I'll probably make a bunch of 16MB SIMMs as well, which would be more economical if you want 64MB.

I have ordered the chips, but shipping is usually super slow. Hopefully within 6 weeks I will have them to make 4MB sticks!

Unfortunately I do not know further easy ways to debug. Having a logic analyser to look at the bus activity during boot would greatly help I'd guess, to see if the CPU does something, and where it would hang. But I have no idea about the boot sequence, this would have to be reverse engineered...