bach@vax1.acs.udel.EDU (Baskaran Subramaniam) (07/18/90)
We just got a MacIIci in our lab today. One of the items in the packing list is a SCSI cable terminator. But, I cannot find any object corresponding to this inside the packing. Could netter tell what it looks like? And what is it used for? Thanks, Baskaran.
cory@three.MV.COM (Cory Kempf) (07/22/90)
bach@vax1.acs.udel.EDU (Baskaran Subramaniam) writes: >We just got a MacIIci in our lab today. One of the items in the packing list >is a SCSI cable terminator. But, I cannot find any object corresponding to >this inside the packing. Could netter tell what it looks like? And what is >it used for? A SCSI terminator looks like a gender-mender for SCSI: i.e. it is about 2-3cm from one SCSI connector to the other (the SCSI connectors are the "centronics" style ones). It is not a gender mender though. If you have an Apple SCSI manual (yes, they do make them), there are several sketches inside. It also tells how to use them. A terminator is just a set of resistors. When a high frequency signal is sent down a wire (as is the case with SCSI, ethernet, video, etc), when it hits the end of the wire, it has a tendancy to bounce. If you terminate the line with a resister (or, in the case of parallel connections, a bank of resistors), The bounce will fade away and not interfere with the signal. (e.g., your disk drives will be happier campers) The rules for use are real simple: If you have only an internal disk, you don't need one. If you have only an external disk, you need one (on either connector spot of the disk). If you have an internal HD and an external, you need one. If you have two or more external HDs, you need one on the first device in the chain and one at the end of the chain. If you have several HDs, including an internal HD, you only need one at the end (the internal one is already terminated). +C -- Cory Kempf I do speak for the company (sometimes). Three Letter Company 603 883 2474 email: cory@three.mv.com, harvard!zinn!three!cory