17 May
2007
17 May
'07
11:15 a.m.
On Thu, 17 May 2007, Jochen Kunz wrote:
On Tue, 15 May 2007 12:53:49 -0700 (PDT)
Mr Ian Primus <ian_primus at yahoo.com> wrote:
Another thing to check: I've seen a couple of DLT7000 drives where the
Molex power connector pins were slightly undersized, making poor contact
with the supply cable. This can cause exactly the same symptoms. I ended
up pinching the female pins on the cable with a small screwdriver to
create a tighter fit. Solved the problem in my case.
And, yes, current requirements for these drives are generally too high for
external SCSI cases intended for hard disks or CD-ROMs. I cannabilized
a mini ITX power supply to provide a heftier source in the last case I
assembled.
Also worth updating the firmware. All of mine were either HP or Compaq
OEM units and both vendors offer Windows and Linux based diagnostic
programs (with firmware uploader) available. At one point, I was able to
find the "official" Quantum version, but it seems to have vanished from
their web site.
Steve
--
I replaced a drive here at work that did just the
same
thing - it requested a cleaning tape very frequently.
Once I had that problem too.
I did some tests and finaly came to the
conclusion that the PSU in the external SCSI box was too weak for the
DLT. It seems DLTs like to suck big peek currents. The PSU could not
cope with this, voltage got instable and confused the DLT.