I recently agreed to assist someone with their PowerBook 100, which although in very good condition cosmetically, doesn't boot.
The owner stated that the original power supply - model M5140Z (Output DC 7.5V, center positive, 2.0A) was probably defective. Currently unsure whether the powerbook was functioning correctly when purchased by the owner.
Firstly with a multimeter I confirmed that the power supply was unserviceable. Using a generic switching supply (Output 7.5v dc, center positive, 1200mA 14.4VA max), the powerbook booted to a dark blue screen. Turning the screen brightness and contrast knobs resulted in no change in the blue screen. These initial boot tests were performed without the main battery or any PRAM batteries installed. The original floppy-drive unit is available and was connected, and to the best of my knowledge, no original system disks came with the unit.
Assuming that after all these years the PBook needed some serious t.l.c, I removed all the components, fortunately with no breakages to plastic inserts etc. And what a joy it was to disassemble this model - unlike many later MacBooks.
The strange 'U' shaped onboard fuse was tested and found ok.
General views follow:
It was no real surprise to find at least 6 leaking electrolytic caps on the main board. Surprised however to observe several areas on the logic board that had apparently been repaired and/or modded.
Not knowing what prompted these repairs(?) or mod enhancements(?) I'm left wondering whether this board would be a good candidate for re-capping.
The serviceability of the SCSI drive is yet unknown, and I'm aware that that chances of it working are very slim, and that replacements are hard to come by, and when available pricey.
The display has yet to be disassembled. I read that there are often a number of caps on the inverter and other boards within the screen assy that don't age well, so I guess they may require attention too. The two caps on the trackball board showed no obvious leakage, but would probably benefit from replacement.
Any comments in general would be appreciated, especially on the condition of the main board.
The owner stated that the original power supply - model M5140Z (Output DC 7.5V, center positive, 2.0A) was probably defective. Currently unsure whether the powerbook was functioning correctly when purchased by the owner.
Firstly with a multimeter I confirmed that the power supply was unserviceable. Using a generic switching supply (Output 7.5v dc, center positive, 1200mA 14.4VA max), the powerbook booted to a dark blue screen. Turning the screen brightness and contrast knobs resulted in no change in the blue screen. These initial boot tests were performed without the main battery or any PRAM batteries installed. The original floppy-drive unit is available and was connected, and to the best of my knowledge, no original system disks came with the unit.
Assuming that after all these years the PBook needed some serious t.l.c, I removed all the components, fortunately with no breakages to plastic inserts etc. And what a joy it was to disassemble this model - unlike many later MacBooks.
The strange 'U' shaped onboard fuse was tested and found ok.
General views follow:
It was no real surprise to find at least 6 leaking electrolytic caps on the main board. Surprised however to observe several areas on the logic board that had apparently been repaired and/or modded.
Not knowing what prompted these repairs(?) or mod enhancements(?) I'm left wondering whether this board would be a good candidate for re-capping.
The serviceability of the SCSI drive is yet unknown, and I'm aware that that chances of it working are very slim, and that replacements are hard to come by, and when available pricey.
The display has yet to be disassembled. I read that there are often a number of caps on the inverter and other boards within the screen assy that don't age well, so I guess they may require attention too. The two caps on the trackball board showed no obvious leakage, but would probably benefit from replacement.
Any comments in general would be appreciated, especially on the condition of the main board.
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