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From: gtc@aloft.att.com (gary.corcoran)
To: jkh@time.cdrom.com, lehey.pad@sni.de
Cc: hackers@freebsd.org
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Date: Thu, 28 Mar 96 14:21:49 EST
Original-From: aluxpo!aloft!gtc (gary.corcoran)
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Original-To: time.cdrom.com!jkh, sni.de!lehey.pad
Subject: Re: Can't read this stupid DAT tape - ARGH!
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Concerning DAT tapes and drives:

>usually in the top right hand corner, there is a
>sequence of three or four symbols that after some examination can be
>considered to represent the letters "DDS", possibly followed by a
>"2".  The other way is the length of the tape: 60 and 90 m are DDS,
>120 m is DDS-2.

I was under the impression that a DDS-2 drive actually writes at a
_higher density_ on *any* DAT than a DDS-1 drive.  For example, if the ads
I see are correct, DDS-2 drives can put 4GB on a single tape without
compression.  What they don't say, of course, is that 4GB is on a 120m
length tape.  But, doesn't that imply that you can get 3GB on a 90m tape?
Whereas a DDS-1 drive can only put 2GB on a 90m tape (without compression).

Please tell me this is true...   ;-}
- I'm just about to order a DAT backup drive, and was planning on getting
a DDS-2 drive (HP C1533) so that I could fit more data on my 90m backup
tapes (the 120m tapes are too expensive).

Gary