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From: penzance!tek@uunet.uu.net (Ted Kim (ATW))
Newsgroups: comp.sys.sun
Subject: Re: SCSI cable length
Message-ID: <18328@shemp.CS.UCLA.EDU>
Date: 12 Dec 88 06:55:51 GMT
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Original-Date: 29 Nov 88 19:52:56 GMT
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erickson@ics.uci.edu (Gary Scott Erickson) writes:
>I would like to attach a shoebox disk to the SCSI port of a 3/60.  Anyone
>know what the maximum length can be?  The person using the 3/60 would like
>the disk in a different room because of the noise.

The recommended maximum is 6 meters. With the cable in the box and the
various connectors, we cut our cable to be 18 feet.

The length figure comes from what we read in the back of the Adaptec 4000
(SCSI controller) manual. It is supposed to be based on the following: 

True (LOW signal) = 0 to 0.4 VDC @ 48 mA (max)
False (HI signal) = 2 to 5.25 VDC 

open collector drivers terminated with 220 ohms to +5 V (nominal)
	and 330 ohms to ground at each end

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