ByteRot :: Disassembling Macintosh IIsi Power Supply

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Disassembling Macintosh IIsi Power Supply

Device	Macintosh IIsi
Difficulty	Moderate
Time	15 - 30 minutes
Steps	8

This guide is by Chris Green on iFixit and is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0. ByteRot mirrors it for non-commercial preservation: formatting changed and photos resized for old browsers; full-size photos and the text are on the FTP in /DOCS/REPAIR. Original guide >>

The Macintosh IIsi Uses a 120/240V AC Power Supply. It provides power directly to the logic board. From there, it is distributed to the rest of the computer.

Tools: Phillips #0 Screwdriver

Step 1

• Start by turning the computer around, and remove this #0 Phillips Screw.
• NOTE: There may or may not be a Phillips #0 screw here, depending on whether or not the computer has ever been serviced.

Step 2

• Now lift these two clips, and slowly pivot the case up.
• You can now seperate the top of the computer from the rest of the machine.

Step 3

• The "SuperDrive" is mounted similarly to the hard drive, and positioned right next to it.
• Push these two tabs out, and lift the drive up.

Step 4

• Flip the drive so it is on top of the power supply, and remove the "Red-Ribbon" cable.
• REMINDER: 1.44MB floppy drives need a ribbon cable with a red stripe on one side. 400KB floppy drives use a ribbon cable with a yellow stripe on one side. 800KB floppy drives can use a red, or yellow striped cable.
• This drive was manufactured by Sony in 1990.

Step 5

• The fan recieves power from two contacts on the logic board and has no connector.

Step 6

• In all of the years that I have worked on this machine, I have found no good way to remove the fan.
• The best way to start, is to push in here on the side of the fan.
• Being careful not to exert too much force, try to push in, and wiggle the fan outward as such. (2nd Photo)
• You can now lift the fan all the way out, and remove it.
• The Fan Power Contacts on the Logic Board:

Step 7

• To remove the power supply, squeeze these two tabs and lift the front up.
• On the back of the power supply, there is a tab that also must be pressed to remove the power supply fully. You can then lift it out all the way. A firm tug may be necessary to seperate the power connector.

Step 8

• Information on the power supply:
• It was made by Sony in 1990, and uses a 10-Pin power connector.

Conclusion

To reassemble your device, follow these instructions in reverse order.

Credit