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Six PowerBook 100


One of my PowerBook 100 is back from the grave!
Nothing worked but I couldn’t give up….
I know from some electrical parts that they work better if the temprature is right …so I got my wifes hairdrayer and heated the MB a little bit… And…yes! I had a blinking floppy.
Now I’m testing HD’s and found one to work!

Will post some pictures later.

Booting from the external SCSI disk didn’t work. I got a walking SCSI sign with number 6 and sometimes number 1 in my screen. This stayed also so if I detached the HD but left the adapter in the PowerBook.

To look into….

I have tested 10 LoBo with 10 displays and to my surprise some combinations work. So it must be that bad but not dead capacitors in the display must be helped by a good LoBo and the other way round.

My Powerbook 100 works, except for a small problem where the screen doesn’t show up. I have found out that this is being caused by 8 small electrolytic capacitors on the back of the LCD which have ALL leaked. I have cleaned up the mess, but the capacitors don’t work (no picture on LCD).

I need to know the type of capacitor to replace them with. They are all marked “3.3 3.5V” and the polarity is noted below that. Can I use anything that is greater than this? E.G. would a 16V 33uF capacitor work as a suitable replacement? or should I get the voltage as close as possible (6.3V 47uF)?

There should be a model/type/serial # on the Caps. If you can, Take one to a radio shack and have a tech look it up. I would think that it should be as close to the original Caps. as possible. if it goes to use the Cap. it could prob get a surge.

The voltage listed on the cap is the voltage at which the dielectric breaks down. So it does not hurt to go over.

I always get confused when reading the values on the caps but I think 33uF is correct.

So a 16V 33uF cap is the type to get?

a replaced the 8 capacitors…

… and the screen now appears: no longer the dreaded dark blue screen. Then I tested this good LCD with some of the spare logic boards that I have in the basement ( and I got the dark blue screen, so it means that the same symptom is shared by two different problems: the 8 caps behing the LCD and something else in the LoB

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