Sony NWS3860, 2150S drive - dump problem

[i6finn at vax87.aud.auc.dk]

I have a problem with a Sony NWS-3860 (NEWS-OS 3.91R, 4.3 BSD) with
a 2150S (NWP-546) tape drive.

The tape that I use is a BULL 3209, DC6150, 600 ft., 12500 FTPI
(a 150 Mb tape).

Level 0 dump:

% /etc/dump 0fsdun /dev/rst40 600 12500 /dev/rsd00e

/dev/rst40 = QIC150
600 = size of tape
12500 = density of tape (BPI)

But I can only get about 70 Mb on each tape !
What am I doing wrong ?

Please E-mail  (i6finn at vax87.aud.auc.dk)

Thanks in advance ...

Finn M. Jensen
Department of Structural Engineering
University of Aalborg
Sohngaardsholmsvej 57
DK-900 Aalborg
Denmark (Europe !)