power line modem - not house mains - lower volts

Archiver

Hi,

Does anyone know if there are power line modems that are made that
allow data to transmitted over say 6 or 12 volts with either AC or
DC (preferably DC)

I know that there are several options (i.e. X-10) that work for 110
VAC, but I need to opperate at a much lower voltage.

This is one example - it is used in cars to transmit data from cd
changer, radio, security ... to the main computer:
http://www.yamar.com/PO-DSI250-01.PDF

Thanks

Paul