IMPORTANT The total length of the cables in a SCSI chain should not exceed 6 meters (20 feet). SCSI cables must have a 110-ohm impedance. For best results, use SCSI cables manufactured by Apple Computer.

mMake sure that the last (or only) device in the SCSI chain has a terminator. Make sure that no other external SCSI device has a terminator.

To ensure accurate transmission of information, a terminator must be at each end of a SCSI chain. Your internal hard disk, which is the first device in the chain, has a built-in terminator.

Some external SCSI devices from manufacturers other than Apple have built-in terminators. (Check the information that came with the device.) If the device at the end of the SCSI chain does not have a built-in terminator, you need to attach an external terminator.

SCSI terminator

If your SCSI device has a built-in terminator, you may choose to use it as your first or last device in the chain, or you may have your Apple-authorized service provider remove any extra built-in terminators. You can attach or remove external terminators yourself.

Connecting Additional Equipment

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Apple 8500 manual Scsi terminator