I was just wondering, not to long ago, why we weren't multiplexing power and signal on the same bus.... It makes sense to me, that with a small power differential between peak signal, and peak DC, we could send the power, and the signal over the same line, and save a line.... The result would be a little more electronics at the far end, but shouldn't be all that expensive. Any Comments.... Might be good for an alarm bus. GRAEME SMITH email: grysmith@freenet.edmonton.ab.ca YMCA Edmonton Address has changed with little warning! (I moved across the hall! :) ) Email will remain constant... at least for now.