[comp.sys.dec] Using TK50s as TK70s

awpsys@ultb.UUCP (Andrew W. Potter) (12/15/88)

Question:

	Has anyone succeeded in writing a TK50 on a TK70 drive?

I understand that this works if you bulk erase the TK50 to eliminate
the TK50 formatting.  I also understand that the party line from DEC is that
the two tapes have different formulations  making this risky.

My question is:

	Has anyone done this?

	How well does it work?

The reason I ask is that I have crates full of old TK50 distribution media
that is dying to be reused.

	- Andy
-- 
Andrew W. Potter                         Email: awpsys@ritvax.BITNET
Systems Programmer                              awp8101@ritcv.UUCP
Information Systems and Computing
Rochester Institute of Technology, Rochester NY, 14623 (716) 475-6994

tony@gvgpvd.GVG.TEK.COM (Tony Ivanov) (12/17/88)

In article <258@ultb.UUCP> awpsys@ultb.UUCP (Andrew W. Potter) writes:
>Question:
>
>	Has anyone succeeded in writing a TK50 on a TK70 drive?
>

Yes, this seems to work fine.  We bought a cheapo bulk eraser from Radio
Shack and bulk erased our TK50s once.  After that, we've used them in the
TK70 drive with no problems and haven't had to re-erase them yet (it's
been about 5 months).  No problems.  We are using them on an Ultrix system,
but that should have no bearing on the results.
-- 
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michael@ddsw1.MCS.COM (Michael Duebner) (12/17/88)

In article <258@ultb.UUCP> awpsys@ultb.UUCP (Andrew W. Potter) writes:
>Question:
>	Has anyone succeeded in writing a TK50 on a TK70 drive?
>I understand that this works if you bulk erase the TK50 to eliminate
>the TK50 formatting.  I also understand that the party line from DEC is that
>the two tapes have different formulations  making this risky.
>Andrew W. Potter                         Email: awpsys@ritvax.BITNET
>Systems Programmer                              awp8101@ritcv.UUCP
>Information Systems and Computing
>Rochester Institute of Technology, Rochester NY, 14623 (716) 475-6994

We have been doing this for some time now.  

You must bulkerase the tapes first, otherwise error messages will result.
After that its no problem.  We are not realizing any errors on the drive
because of the use of TK-50K media.

We also have quite a few DEMO tapes around the shop that have been converted
to scratch backup media.  However, all permanent backups are still being
made on TK-52K (TK-70 media) tapes.

I hate to find out a year down the road that the data is not safe.  Now if
the drive could also write TK-50 mode tapes it would be a really good deal.



Michael Duebner	                UUCP : michael@ddsw1.MCS.COM
Tech Svc, Buffalo Grove, IL             	312/541-6550

lancaster@misadel.oz (12/18/88)

In article <258@ultb.UUCP>, awpsys@ultb.UUCP (Andrew W. Potter) writes:
> 	Has anyone succeeded in writing a TK50 on a TK70 drive?
> 

Me too I've got them comming out of my ears.

So if I can reuse the TK50k's instead of buying more TK52's then it would be
great.

-- 
==============================================================================
|Robert Lancaster                  |    lancaster@misadel.oz                 |
|Management Information Systems    |                                         |
|125 Dew Street                    |  I can write in 101 computer languages  |
|Thebarton, South Australia, 5038. |  but in English forget it.              |
==============================================================================

taylort@decus.com.au (Trevor Taylor (Graphics SIG Chairman)) (01/04/89)

In article <258@ultb.UUCP>, awpsys@ultb.UUCP (Andrew W. Potter) writes:
> 	Has anyone succeeded in writing a TK50 on a TK70 drive?
> 
Just out of curiosity, we took a brand new TK50 and wrote a backup
saveset to it on a TK70. It worked OK. However, as a matter of
principle we do not intend to use TK50s this way. I can't comment
on the reliability, but using BACKUP it should be OK even with a
few soft errors.

What really irked us however, was that in the easly days of TK70s
we could not get many and one of the operators mistakenly used a
few in a TK50 drive one day. Result -- TK70s that you can no
longer use except as TK50s. You cannot even re-initialise them
because the "smart" drive checks the tape first and says "Oh no,
this is a TK50!".

karl@ddsw1.MCS.COM (Karl Denninger) (01/17/89)

In article <524@decus.com.au> taylort@decus.com.au (Trevor Taylor (Graphics SIG Chairman)) writes:
=In article <258@ultb.UUCP>, awpsys@ultb.UUCP (Andrew W. Potter) writes:
=> 	Has anyone succeeded in writing a TK50 on a TK70 drive?
=> 
=Just out of curiosity, we took a brand new TK50 and wrote a backup
=saveset to it on a TK70. It worked OK. 
=
=What really irked us however, was that in the easly days of TK70s
=we could not get many and one of the operators mistakenly used a
=few in a TK50 drive one day. Result -- TK70s that you can no
=longer use except as TK50s. You cannot even re-initialise them
=because the "smart" drive checks the tape first and says "Oh no,
=this is a TK50!".

Bulk erase the tape and try again :-)

It takes a reasonably good bulk eraser to get the tape, but if you succeed,
you've got a truly "blank" tape again.   It appears that what the drive is
checking is the volume header on the initialized tape.  

(Disclaimer:  It works for us, no idea what it'll do for you.)

--
Karl Denninger (karl@ddsw1.MCS.COM, ddsw1!karl)
Data: [+1 312 566-8912], Voice: [+1 312 566-8910]
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