For some reason it all seems to be working now (see below). (At least 
the 1600 bpi light is on.)  I don't really know at this point what I 
was doing wrong.  In any case the 556 bpi message is a little confusing.


.a mta1 mta0
MTA1 Assigned as MTA0

.r bart

*density 1600
Density for MTA1 will be 556 bpi.
*ucopy
Want OUTPUT tape rewound before starting? n
Want INPUT tape rewound before starting? n
DART version 5  tape header
Recorded  10:39 29-Nov-75,  by [  1,LCS] USER class
WOM2           1,LCS
THORN2         1,LCS↑C
↑C

.r ppsav