OT: SLR 5 Tape drive vs DAT

[Bill Vermillion]

On Wed, Feb 02 10:09 , Joe Chasan gie sprachen "Vyizdur zomen 
emororz izaziz zander izorziz", and continued with: 

> On Wed, Feb 02, 2005 at 09:43:58AM -0500, Scott Walker wrote:
> > One of my customers has an old QIC tape drive that has finally died.

> > I told him to get a quote on a DAT drive to replace it.

> > The hardware guy quoted him a Tandberg SLR 5 Tape Drive for $610.

> > How does this compaire to a DAT drive. This customer only has
> > about 2gb that needs to be backed up.

> > What really got my curiosity up is the fact that they quoted
> > hime $50 each for the SLR 5 Data Cartridges. What makes them
> > so expensive?

> i'm sure bill vermillion or tom podnar will pick up on this
> thread with some more in-depth knowledge.

> the main advantage of the SLR5 in your case would be the ability to
> read/re-use the QIC tapes you already have.

Read would usually be the operative word - because you problaby
upgrade because of space problems.  I'd have to look at the charts
from the mfrs - but most QIC media can be read - but there are some
that can not.  Most of my knowledge started so long ago when our
school got a Brush SoundMirror audio tape machine and I later
recorded our high school band on one - and got hooked on magnetic
media.  That's been close to 50 years ago.   I worked with audio
tape daily in broadcast before I moved to recording where I used
a LOT of tape.  My least amount of experience is in data - but
magnetic technology is all the same at the heart of it.

Recording has always fascinated me since the first time I heard my
voice recorded and played back - when I was probably about 8 years
old on a friend of my father Wilcox-Gay Recordio - with platic
coated paper record.  That was soemtime during WWII.

> the DAT media may go under $12 at buy.com, whereas the SLR5 media is
> three times that (which is still a little cheaper than your source).
> 
> the SLR5 is a 4/8 GB tape, price for that size drive is about on par
> with a DDS-3 12/24 GB DAT drive - i don't have specs in front of me,
> but I'd guess the dds-3 should be much faster than the SLR5 (and 
> certainly dds-4 20/40 GB DAT and the dds-5 36/72 GB).  you can see 
> where you'd get more bang for the buck.  

> I'm sure the QIC market share has been significanty eroded which may
> account for the media price.

Take a look at a QIC drive.  The tape path and stability are
dictated by the cartridge with a rigid base plate and the internal
belts to support the tape, the moveable door for tape head access,
etc. You may not notice the internal belt but it supports the tape
on the trip around the full length of the cartridge.

Notice also there is a mirror so that when the EOT holes pass by
the light will be refelcted so the tape does not run off the end of
the reel.  You will also notice that the pinch roller is part of
the cartridge that the capstan of the drive presses against.

It's a pretty rugged piece mechanically.  And it was designed for
reliable data backup.  Having the pinch roller with the tape means
you don't have to take a drive apart to replace a pinch roller when
the rubber hardens.    It's more of a fail-safe design

The DAT spawned the DDS drives.   So it was a consumer audio device
adapted for data storage because it was so much cheaper.   There are
not that many mechanical parts in the DAT/DDS cartridge as the
smarts are in the drive.  It became popular because it was cheaper.
But as data storage increased the tape in it had to be improved and
it's basically at the limit of magnetic storage ability.  Sony
had said there would be nothing past the DDS-4 and went with their
AIT technology.  But others went ahead with the DDS-5.   But that
just has to be the limit.

The AIT is 8MM so it give twice the arial density for the same
length of tape.  IMO the DDS will slowly fade.  For inexpensive
solutions the Ecrix VXA [ now part of Quantum ] are a decent
alternative to DDS.  8MM tape and the VXA-1 lists for $699 - with
33/66GB capacity - and that's with internal HW compression - not
the fudged capactiies often shown with things like the Travan's
that depend upon SW compression to get the capactiy.

Tom posted the specs and prices on the AIT a couple of weeks ago -
for people who need larger capacity.

> Also, i'm not sure there are any other QIC/SLR drive vendors
> still making drives anymore other than Tandberg, whereas the
> DAT market has HP/IBM/Certance/Sony to name a few.

The DDS market is going to go away as data storage increases.
You can easily get 200GB on the 8mm products but DDS just wont cut
it at that capacity, and as they get larger you will need changers.

Pretty amazing at how far tape has come since the early QIC tapes
of 20MB that had 4 tracks on them to the ones today with huge
number of parallel tracks.

Bill

-- 
Bill Vermillion - bv @ wjv . com