[rescue] VS80 DLT tape drive question

[Curtis H. Wilbar Jr.]

Mr Ian Primus wrote:
> --- "Curtis H. Wilbar Jr." <rescue at hawkmountain.net>
> wrote:
>
>   
>> I might have to experiment... even with Ultra SCSI,
>> 6M/sec should
>> be attainable.... so if the drive tops out (in
>> compressed mode) at 6M/sec
>> I shouldn't be shoeshining even at 10M/sec SCSI.
>>
>> I did have the tar running as time tar ... so I got:
>> 313m34.661s to backup 43678188K (as reported by du
>> -sk)
>>
>> That translates to: 42654.48M/18814.66s = 2.27M/sec
>>
>> Most of the data was .tgz, .iso, .zip, etc... so I'd
>> expect to see not
>> much over 3MB/sec... so... maybe not bad considering
>> there were
>> periods of shoeshining.
>>     
>
> Yeah, it should be faster than that - and it ought not
> shoeshine too much. Do you have a cleaning tape for
> the drive? If the heads are dirty, poor performance
> will result. A CleaningTape III is used for all of the
> DLTX000 drives. Don't know about VS80, but I'd
> _imagine_...
>
>   
>> Now... on bulk erasing DLTs... any idea of a Radio
>> Shack bulk eraser
>> is going to have the 'punch' required ?  works great
>> on floppies (I've
>> 'rescued' lots of floppies that would format with
>> bad sectors by bulk
>> erasing and reformatting)... but I seem to recall
>> trying a VCR tape at
>> one point and it not being very effective.
>>     
>
> Yeah, I don't know how much that Radio Shack eraser
> will be able to do - 3 1/2" HD floppies are 720
> orsted, and DLTIV tapes are 1850. VHS is only 700 - so
> it should work on those if it worked on floppies.
> Worth a shot though. For the most part, you just need
> to erase enough of the header info to trick the drive
> into re-writing it in a new format.
>   

The RS eraser.... NO GO !  I gave it 30 seconds on the top,
30 seconds on the bottom, I can still READ ! the tape....

>   
>> on bulk erasing.... bulk erase top, top and bottom,
>> or the sides ?  Which
>> way will orient the magnetic field of the bulk erase
>> for maximum
>> effect ?
>>     
>
> I'd bulk erase the top, bottom, front, edges, back,
> and the clear plastic case it came in. You need all
> the help you can get with that little eraser :)
>
>   
Too bad the drive can't erase (i.e. separate full width erase head)...

What sort of bulk eraser would be required to do DLT tape ?

Or since DLT has been around long enough... just try finding used
DLT8000 formatted media or unused media... ?

-- Curt

> -Ian
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