Apple twentieth anniversary mac Service Manual

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Connecting the keyboard
To connect the keyboard to the back of your computer, follow these steps:
1
Pass the keyboard cable under the computer.
2
Plug the keyboard cable into the port marked with the 
V icon on the back of the computer, and press
the cable into the cable guides.
Be sure to use the correct port, which is marked with the V icon. Don’t use any other port, even if the
cable seems to fit.
By the way:  A port marked with the V icon is called an Apple Desktop Bus (ADB) port.
Port marked with a V icon
Cable guides
Setting Up     
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