cbradley@Busl.COM (Chris Bradley) (12/07/90)
Over the past several months, a number of messages in this newsgroup have mentioned that having a system unit fan that blows the wrong way may increase the chances of dust accumulation inside the magneto-optical disk drive in a NeXT Computer. In the first production-runs of the NeXT Computer, the cooling fan operated in a reverse direction from that of later units. In these early machines, the fan drew cool air inwards -- mostly through the optical drive slot in the front of the cube -- and exhausted the heated air through the fan grating in the rear of the system unit. Drawing air in through the optical disk slot allowed for the accumulation of dust inside the magneto-optical drive, which has been blamed for the early failure of some OMD-1 drive units. In a few cases, it seems that the problem was aggravated by leaving an optical disk in the drive for long periods of time: several weeks or months. In all cases, the environment appears to be the most important factor. If you leave your cube on the floor, or if the items in the surrounding area seem to quickly gather a surface layer of dust, then you should take precautions. NeXT redesigned the cooling system to reverse the airflow and to add more ventilation ports to the cube, providing more air exhaust routes than solely through the optical drive slot. According to Ken Jochims of NeXT Computer, Inc., the last of the "wrong-way fan" machines was shipped on or about September 28, 1989. The serial number of the last "wrong-way fan" machine was in the neighbourhood of AAK0004000. You can test your machine to see if its fan blows the "right" way: take a small piece of paper and place it against the fan grating on the rear of the system unit. If the indrawn airflow causes the paper to stick against the fan grating, then your cube probably has the new airflow system. If, instead, the paper blows away from the fan grating, then your machine is probably using the older airflow design. For users with older cubes that employ the original cooling design, NeXT is providing a head cleaner, a disk cleaner, and a dust filter for the optical disk drive. Part # Price Description ======= ===== ========================================== S3901-p $60 Canon OM-HC1 Head-Cleaning Kit S3902-p $15 Canon MO-CK1 Magneto-Optical Disk Cleaning Kit S3900-p $10 MO Drive Filter These items are available at NeXT Authorized Service Centers. -- Chris Bradley | "Nothing is more certain than incertainties; Businessland Advanced Systems | Fortune is full of fresh variety: Dallas, Texas US | Constant in nothing but inconstancy." cbradley@busl.com | -- Richard Barnfield 1574-1627
bennett@mp.cs.niu.edu (Scott Bennett) (12/08/90)
In article <1990Dec7.002527.358@Busl.COM> cbradley@Busl.COM (Chris Bradley) writes: >Over the past several months, a number of messages in this newsgroup >have mentioned that having a system unit fan that blows the wrong >way may increase the chances of dust accumulation inside the >magneto-optical disk drive in a NeXT Computer. > > [much good info deleted --SJB] > > Part # Price Description > ======= ===== ========================================== > S3901-p $60 Canon OM-HC1 Head-Cleaning Kit > > S3902-p $15 Canon MO-CK1 Magneto-Optical Disk Cleaning > Kit > > S3900-p $10 MO Drive Filter > >These items are available at NeXT Authorized Service Centers. Yes, Chris, but when will *optical disks* be available from NeXT Authorized Service (and Sales:-) Centers? I ordered mine about a month ago and I'm still waiting. When they show up and I can make a backup of the NeXT software disk, it will be safe to start *using* my computer that has been sitting idle since it arrived a month ago. Got any news for us would-be NeXT users? >-- >Chris Bradley | "Nothing is more certain than incertainties; >Businessland Advanced Systems | Fortune is full of fresh variety: >Dallas, Texas US | Constant in nothing but inconstancy." >cbradley@busl.com | -- Richard Barnfield 1574-1627 Scott Bennett, Comm. ASMELG, CFIAG Systems Programming Northern Illinois University DeKalb, Illinois 60115 ********************************************************************** * Internet: bennett@cs.niu.edu * * BITNET: A01SJB1@NIU * *--------------------------------------------------------------------* * Visit the scenic Illinois Craters! Just 10 minutes * * from New Chicago! * **********************************************************************
garnett@cs.utexas.edu (John William Garnett) (12/08/90)
In article <1990Dec7.002527.358@Busl.COM> cbradley@Busl.COM (Chris Bradley) writes: >1989. The serial number of the last "wrong-way fan" machine was >in the neighbourhood of AAK0004000. > I can provide one piece of evidence that verifies that AAK0004000 number. My cube has a fan that blows in the right direction and its serial number is greater than AAK0004000 (less than 500 greater). However, NeXT Inc. has claimed to at least one person (via telephone) that the machines with the new fan design were introduced over time (mixed in with machines having the old style fan) so that there is no sharp cutoff in serial numbers between the two models. I would assume that if the previous sentences in this paragraph are correct, then some small number of the cubes with serial numbers sequentially less than AAK0004000 have new style fans. -- John Garnett University of Texas at Austin garnett@cs.utexas.edu Department of Computer Science Austin, Texas
cnh5730@calvin.tamu.edu (Chuck Herrick) (12/09/90)
In article <1990Dec7.002527.358@Busl.COM) cbradley@Busl.COM (Chris Bradley) writes:
)For users with older cubes that employ the original cooling design,
)NeXT is providing a head cleaner, a disk cleaner, and a dust filter
)for the optical disk drive.
)
) Part # Price Description
) ======= ===== ==========================================
) S3901-p $60 Canon OM-HC1 Head-Cleaning Kit
)
) S3902-p $15 Canon MO-CK1 Magneto-Optical Disk Cleaning
) Kit
)
) S3900-p $10 MO Drive Filter
)
)These items are available at NeXT Authorized Service Centers.
Would use of these items benefit optical drives in "new" cubes?gilgalad@caen.engin.umich.edu (Ralph Seguin) (12/09/90)
In article <1990Dec8.043823.22185@mp.cs.niu.edu> bennett@mp.cs.niu.edu (Scott Bennett) writes: > Yes, Chris, but when will *optical disks* be available from NeXT >Authorized Service (and Sales:-) Centers? I ordered mine about a month More interestingly, when will we be able to buy inexpensive magneto-optical cartridges? Double sided ones? $150/disk is getting up there for a student's budget :) > Scott Bennett, Comm. ASMELG, CFIAG > Systems Programming > Northern Illinois University > DeKalb, Illinois 60115 >********************************************************************** >* Internet: bennett@cs.niu.edu * >* BITNET: A01SJB1@NIU * >*--------------------------------------------------------------------* >* Visit the scenic Illinois Craters! Just 10 minutes * >* from New Chicago! * >**********************************************************************