Are old SCSI tape drives not all created equal?

[js at cimmeri.com]

On 8/21/2016 12:46 PM, Chuck Guzis wrote:
> On 08/21/2016 10:12 AM, js at cimmeri.com wrote:
>
>> The final matter is that I'd still like to get the Teac to function
>> with some software, just to watch it operate (you have to really
>> like mechanical things to understand this strange fascination).
>> Having put some time and $ into the Teac, it'd be nice to get some
>> reward, even if only then it gets placed on the shelf afterwards.
>
> Back in the day, I wondered if the DDS drives being as complex as they
> were, with the skinny less-than-4mm wide tape could even have the
> possibility of any longevity.
>
> But the old DDS-1 tapes I recorded more than 20 years ago are still
> quite readable as are the DDS-4 tapes I wrote over a decade ago.  One
> advantage that DDS (and DLT...) has over most of the "QIC" tapes is that
> they use a read-after-write system like the big 1/2" tape drives, making
> a separate verification pass unnecessary.  They also tend to follow the
> ANSI sequantial-access SCSI standard more carefully.
>
> You may want to consider DDS or DLT for your DEC gear.
>
> --Chuck


Chuck,

   I agree wholeheartedly with your assessment.  I do have a
variety of 4mm, 8mm, and DLT tape drives in addition to the
problematic ones discussed earlier.  But trying other, novel
mechanisms that contain brilliant design ideas is quite a
bit as fun as well, beyond just the practical concern.

   Bet: I think 9 track or DLT will outlast them all, mechanism
longevity included.  Specifically, I think my HP 7970E will
likely outlast every other mechanism / media combination I've
got, with the only uncertainty being the longevity of 9 track
media... but there, at least I've got a Mark III tape cleaner.

- John