Posted by Green Xenon [Radium] on 09/30/07 05:34

On Sep 29, 8:59 pm, dpl...@radagast.org (Dave Platt) wrote in
http://groups.google.com/group/uk.tech.digital-tv/msg/872fdf9b0c765bd0 :

> In article <46fefb70$0$7493$4c368...@roadrunner.com>,
> Green Xenon [Radium] <gluceg...@excite.com> wrote:
>
> > > Sure it is possible. It won't be of any assistance to you (or to
> > > anyone else since you can't put 8 pounds in a 1-pound sack.
> > > Bandwidth is bandwidth, no matter how you slice it. Do you
> > > really think that nobody has thought of various methods of
> > > transmitting video over low-bandwidth paths? If so, you need
> > > to study not only science and engineering but the HISTORY
> > > of science and engineering.
>
> >There are 8-bits-per-symbol, only 1 baud. The symbol is split into 8
> >parts. Each part is 1-bit.
>
> >How is this “putting 8 pounds in a 1-pound sack?”
>
> >It’s more like “putting 1 pound in a 1-pound sack”
>
> You are using the word "split" without defining what you are meaning,
> and I think you may be using the word "bit" in two different ways (as
> in "a single binary digit's worth of information" and "a part")...
> maybe I'm wrong about the latter.
>
> Sure, you can carry 8 bits of information per symbol, at a rate of one
> baud. That's an information rate of 8 bits per second, which isn't a
> terribly useful amount of information.
>
> What I *think* you are saying is something along the lines of
>
> "If there's no way to carry N bits of information per symbol (where
> N is a large number) at a rate of 1 symbol per second, in a
> specified bandwidth, over a channel having a certain amount of
> dynamic range / signal-to-noise ratio available, then I'd
> like to somehow divide each symbol into eight sub-symbols which
> each carry N/8 of the information, but which still make up only one
> symbol per second. My hope is that these eight sub-symbols could
> be easier to transmit, somehow, than a single symbol carrying N
> bits, and that I could thus transmit them more easily but without
> using any more bandwidth. Can I do that?"
>
> If that's what you're asking, the answer is "no".
>
> Once you hit the theoretical information limit of the communication
> channel (which is set by the bandwidth you use and by the amount of
> noise on the channel) you can't do any better than that. No matter
> how you modulate (changing the baud rate, the amount of information
> per symbol, etc.) you can't do better than this.
>
> And, as we've been trying to make clear, your goal is quite far beyond
> the theoretical limit. You just can't get there. You're trying to
> put all of Lake Erie in a water-glass.
>
> Let it go, Radium.

Within physical-possibility, what is the largest amount of
bits-per-symbol [assuming a baud-rate of only 1-bit-per-symbol] that can
be reached without the highest-voltage causing any clipping, generating
any temperatures above 70 Fahrenheit, resulting in any harm to
anyone/anything [including the equipment itself], or shortening the life
of the equipment and without the lowest-voltage being lost in the noise?
What is the maximum-possible amount of discrete levels between the
highest and lowest voltage in such a signal?

An 8-bit signal can have a maximum of 256 different voltage levels
between the highest and lowest voltage. Right? Go too high and the
signal clips, go too low and the signal will not be recognized.

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