I know this question probably comes up a lot, as I've noticed from the posts....
I want to build a very short range transmitter for operation in my living room. Basically, I want to take the output of my subwoofer channel from my home theater reciever and convert it to a digital signal for broadcast to another part of the room. I'd like to be able to hide the subwoofer and relocate it as needed without having to reroute wires.
I think I can find enough info for the various circuits. However, I'm pretty ignorant on FCC regs. I'm aware that the FCC requires that the signal level be less than 250 microvolts at 13 meters from the antenna. But, I have no idea how to test this. I understand this is typically done in a lab, so of course, I wouldn't be able to test this. I also understand that there is a formula for approximate conversion from the transmitter power to signal strength: (P*G)/(4*pi*D^2) = (E^2)/(120*pi) P=Transmitter Power (Watts) G=Antenna Gain D=Distance (m) E=Field Strength (V/m)
Ok, to make a long question even longer, I guess I'm asking if there's an easy way to make sure I'm not violating FCC regs. I'd like to know that by experimenting, I'm not going to get sued, fined or go to jail. And also, I'd like to respect proper use of the spectrum.
I apologize for my ignorance. I'm a power engineer by education and am trying to revive my long lost interest in elecronics. I can't imagine a more useful thing to know.