yeah ok but 1GHz isnt ultra-sound
20kHz to ~ 100kHz is ultrasound
I again suggest what steve suggested many posts back
there are ways for putting a digital signal onto a power line
google BPL
But its a VERY DIRTY way of communicating data/voice or whatever
it causes masses of interference. A lot of the commercial installations around the world were forced to shutdown because of the intereference they caused to broadcast radio/TV and amateur radio operations
I wouldnt wanna live within 5 miles of you if you were messing with that sort of thing
now ya see ... if you had explained clearly what you were trying to do, way back in your first post or 2 ... we could have saved 20 posts of trying to figure out what you were on about
and with your poor descriptions etc it shows that you have an obvious lack of knowledge with electronics, You dont seem to have the saftey know-how to do a project like this
you should really be looking at commercial units
Dave