Cliff, it is AC powered only. I got one I never used with a package deal, and later sold it. I did not check it out much, so I do not know all of the capabilities.
The RMR-D100 has a male seven pin dongle, that theoretically could plug into the I/O female 7 pin on the SBM, and provide output to a jb3. The unit is intended to be a remote control unit for the sony DAT portables (M1) primarily, but would have no remote capabilities with the SBM. Not sure if it would work or not, I would think no, but that is only a guess.
hope that helps
pic of similar unit RMR-D3: