Choreboy wrote:
>> Couldn't technology analogous to a megaphone be applied to dialup as >> well as DSL?
> Yes.
>> Ah, crosstalk! It seems to me that if DSL uses the same wire dialup
>> used, the same crosstalk will be present.
> Not necessarily. Remember AM and FM radio waves go through the same
> air, but AM is much more sensitive to lightning and other static than > is FM.
> DSL service may be arrangeed to minimize crosstalk.
You've hit it on the head. Both AM and FM use radio bandwidth, but each uses a different form of modulation. AM stands for Amplitude Modulation -- the amplitude is how high a particular sine wave rises or falls. FM is frequency modulation, the carrier frequency varies depending on what signal is being fed to it.
It's sort of the same setup on DSL with the data signals occupying a higher frequency.