Apple Macintosh PowerBook 150 - Manual (Page 108)

4 Repeat step 3 for each additional device you want to connect.
The illustration shows where to add cable terminators.
IMPORTANT The total length of a SCSI chain should not exceed 20 feet
(6 meters). Apple SCSI cables are designed to meet this restriction. If you
are using SCSI cables from another vendor, check the length of the chain.
WARNING Once your SCSI devices are connected, always turn them on
before turning on your PowerBook. If you turn the computer on first, it
may not be able to start up, or it may not recognize the SCSI devices.
Terminator
(If this SCSI device has an internal
terminator, omit this external terminator.)
SCSI peripheral interface cables HDI-30 cable
Terminator
(If this SCSI device has an internal
terminator, omit this external terminator.)
Terminator
(If this SCSI device has an internal
terminator, omit this external terminator.)
Terminator
HDI-30 cable
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