Michael_J_Ward@cup.portal.com (12/03/90)
Per my earlier message on incompatibilities of the fx and the apple cd-rom
drive, mail fell into two camps: one had the cd drive connected directly to
the fx and had no problems, and the other had other items on the SCSI bus and
had loads of problems. Apple's official "fix" is to try different lengths of
SCSI cables between the devices.
Clearly they are having problems with reflections and/or impedance
mismatches between the devices and the terminations. These show up as
resonances in the cables and may be worked around by selecting lengths of
SCSI cable which do not aggravate the mismatch.
I connected my cd-rom drive directly to the fx and have had no problems.
Perhaps Apple would like to say something further to us...time@tbomb.ice.com (Tim Endres) (12/03/90)
In article <36485@cup.portal.com>, Michael_J_Ward@cup.portal.com writes: > I connected my cd-rom drive directly to the fx and have had no problems. > Perhaps Apple would like to say something further to us... > > Cable length, impedance, and reflectivity have been problems with the Apple SCSI bus since the bus first appeared! Granted, certain Macintoshes/Systems have had better/worse performance in this area, but I have *never* had a Macintosh that did not have a SCSI cable problem with one or more of my devices. It usually depends a lot on the SCSI device being hooked up. The moral of the story is to buy your SCSI cables *carefully*. Third party cables that are thin and long are obvious recipes for problems. Get short thick cables, preferrably from Apple. I know that Monster Cable (the guys who did the *thick* audio wiring) now makes a SCSI cable. That is probably a good bet. BTW: I run an fx with the CD ROM being the third device on the chain and have *no* problems. Just good cables. tim. ------------------------------------------------------------- Tim Endres | time@ice.com ICE Engineering | uunet!ice.com!time 8840 Main Street | Whitmore Lake MI. 48189 | (313) 449 8288