If the TK50 can be moved to a VMS box and
the  DISMOUNT MUA0  be made to work, then
that means the rewind/dismount capability
exists IN the TK40, and DEC chose not to
implement it in the Ultrix mt command and
maybe also in the BSD's.  Anyone know if that
code exists somewhere, or how to do that?
Maybe it is time for an mt source update?
A tape retension command would be ideal, as
well as something to forcibly dismount the
drive if a tape got stuck.  I don't suspect
that the tape is all the problem, but that the
hardware of the drive gets confused and then
can't recover or reset from it, if a tape gets
way into the reel and stuck or lost track of.

As to workability of the hardware in scsi
vs mscp, I don't have a good feel for that.
I run both types of drives, and they seem to
work, if clean and that sort of thing.  The
scsi box is a buggerbear to have to go into
and disassemble to remove a stuck tape, compared
to the BA123 cabinet, for example, though.  So,
I tend to prefer the Qbus version as opposed to
the scsi version, unless I need to write or
read something on a later scsi VAX.

Speaking of scsi.... (I know, don't even bring
it up....(:+}}....) anyone got any spare scsi
Qbus mscp or tmscp controllers laying about,
just looking to be used?  I could sure use a
tape scsi board, so I can bring up some of
those nice old 9 track reel decks I have sitting
and gathering dust.....(:+}}...  Also, I sure
could use a pair of mscp scsi boards, or maybe
combo boards.  Yeah, I know.... dream on........
I would be willing to pay a reasonable rate, but
not the way out of line ripoff the used board
mongers want to stick you for.  They seem to be
of the opinion those things are pure gold or
platinum or somesuch.....(:+}}...

Just thinking out loud, again.

Bob