> 
>     Does anyone know whether or not the TU-58 under construction for the
> 11/750 will work for the 11/725 or the 11/730? I have Ultrix for the 11/750
> but the TU-58 tapes will not work on its baby brothers.
> 
What exactly is your problem?
11/730 is not (yet) supported by NetBSD, but it would be rather
trivial to fix support for it, most of the needed files are in
4.4BSD. (But not the IDC device driver, it has to be written).
Ultrix does not support 11/730, at least not in version 4.
11/730 also use MRSP instead of RSP to communicate with 
the TU58, and there are no MRSP support in the current driver.

-- Ragge