castrwilliam
New member
Recently I picked up a Powerbook 170 from a surplus store. After ordering a power brick off Amazon (brand new, not the Apple version), it would at least boot to a gray screen with a cursor, but the hard drive was dead and seemed to hang the boot process so it never got to the question mark icon. I opened it up, took the hard drive out and it got to said icon, but since I don't have a working floppy drive anywhere anymore, all I could do is put in a blank floppy and see that it accessed one and then ejected it. I had the hard drive out and eventually decided to open it and un-stick the heads and put it back in to see if I could even get it to initialize. Before, it would spin up and down but there was no evidence it would ever try to seek.
The drive seems to spin up and initialize just fine after that, but I have a far worse problem now.
When I put the machine back together, I think I must have hurt the CPU/FPU card because now it won't do anything at all. The screen lights up, displays the weird pattern you get before the gray screen, but there's no chime and neither of the drives spin up. Before, it had some manner of loose connection. All the standoffs on the bottom of the case had separated from the case itself so I had to fiddle with it a few times I put it back together to get it to boot. Usually it would act like it does now when I re-assemble it but after fiddling with the ribbon between the top of the case and the CPU card it would eventually chime and then after a little more it would boot fully once again, but now it doesn't even chime after trying over and over.
I decided to fully disassemble it until I could figure out a way to fix the standoffs so it didn't get stressed any further. To make matters worse, the standoffs over the hinge near the display panel were broken as well and when I tried to separate the front of the LCD case from the back (like it says in the Apple service manual) the left-hand one tore the data cable to the display panel and broke the four leftmost traces. I found another on eBay and ordered it last night even though I'm not sure I'll ever get the motherboard to boot again because I'm sure parts for these machines are impossible to come by and it was only $10.
So, the first thing I want to know is: will/should the system boot to a chime with only the lower motherboard and the CPU card and a charger connected? I've tried this but still nothing happened, although I got an audible pop out of the headphones. Second, if not, how would I go about fixing this with absolutely zero diagnostic information? Does anyone have a schematic for these perhaps? I've already booted it without the 2MB RAM card on the off chance there was ESD damage or something to that, but nothing changed.
I know what I did was fairly rash and stupid but I'm not about to throw this thing out.
I have a degree in EE so if I could get access to a logic analyzer, some schematics and a LOT of time I might be able to find out exactly what got bent out of shape and how, but that's a long shot. Old Macs didn't have debug headers, did they? I don't see any.
Photos of the releveant boards are coming as a reply to this post. They look mint, I just wish they would work.
The drive seems to spin up and initialize just fine after that, but I have a far worse problem now.
When I put the machine back together, I think I must have hurt the CPU/FPU card because now it won't do anything at all. The screen lights up, displays the weird pattern you get before the gray screen, but there's no chime and neither of the drives spin up. Before, it had some manner of loose connection. All the standoffs on the bottom of the case had separated from the case itself so I had to fiddle with it a few times I put it back together to get it to boot. Usually it would act like it does now when I re-assemble it but after fiddling with the ribbon between the top of the case and the CPU card it would eventually chime and then after a little more it would boot fully once again, but now it doesn't even chime after trying over and over.
I decided to fully disassemble it until I could figure out a way to fix the standoffs so it didn't get stressed any further. To make matters worse, the standoffs over the hinge near the display panel were broken as well and when I tried to separate the front of the LCD case from the back (like it says in the Apple service manual) the left-hand one tore the data cable to the display panel and broke the four leftmost traces. I found another on eBay and ordered it last night even though I'm not sure I'll ever get the motherboard to boot again because I'm sure parts for these machines are impossible to come by and it was only $10.
So, the first thing I want to know is: will/should the system boot to a chime with only the lower motherboard and the CPU card and a charger connected? I've tried this but still nothing happened, although I got an audible pop out of the headphones. Second, if not, how would I go about fixing this with absolutely zero diagnostic information? Does anyone have a schematic for these perhaps? I've already booted it without the 2MB RAM card on the off chance there was ESD damage or something to that, but nothing changed.
I know what I did was fairly rash and stupid but I'm not about to throw this thing out.
I have a degree in EE so if I could get access to a logic analyzer, some schematics and a LOT of time I might be able to find out exactly what got bent out of shape and how, but that's a long shot. Old Macs didn't have debug headers, did they? I don't see any.
Photos of the releveant boards are coming as a reply to this post. They look mint, I just wish they would work.
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