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Re: The end of HF



> Ain't no way they can send a 20mbps BROADBAND signal over a 2000' long
> open wire transmission line  (power line) through your back alley 
> without
> wiping out HF!

Even if it's a differential signal?  That shouldn't get out much past 
the near field .. and there are economical reasons to do that, because 
otherwise they lose efficiency to radiation loss.  The less signal they 
lose (i.e. radiate) the farther their signal can go along the 
transmission line.  Same problem as feeding a Windom with a single wire 
vs. a dipole with a ladder line.

Of course, it's not a *straight* balanced line, and there are impedance 
bumps here and there from nearby metal and ferromagnetic objects, and 
there will probably be radiation from those bumps, but I'd think they'd 
want to tune the system to lose as little of the signal as possible.

But .. you do have a point .. it'd be nice if they picked a carrier 
frequency that's somewhere outside the HF bands, and maybe used spread 
spectrum techniques to minimize impact on any particular frequency, but 
that's just what I'd do ..

"Oh yeah? Well, I speak LOOOOOOOUD, and I carry a BEEEEEEEger stick -- 
and I use it too!"  **whop!**   -- Yosemite Sam

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