[ale] tar restore help

[bdowd at dentfirst.com (Brian Dowd)]

I have a SCSI tape drive (/dev/st0) onto which I can archive all my
files by using tar cvf /dev/st0 /
I can list the tape's contents with tar tvf /dev/st0 and can monitor the
drive's status with mt -f /dev/st0 status
However when I try to extract (restore) the files with tar xvf /dev/st0
/ the tape runs and runs finally telling me that
tar: / Not found in archive
tar: Error exit delayed from previous errors
Am I naming the archive correctly? I tried using '/home/myname' instead
of '/' Still didn't work.
Any ideas, anyone?