>Well Dale, we will have to respectfully disagree with each other. The
>difference in copyabiltiy between CW and Pactor when they are down in
>the noise is simple: Pactor knows when an error has been made, CW
>doesn't. If you send dit-dit-dit-dah and noise or QRM causes you to
>miss a dit and copy it as U instead of V, you have no way of knowing
>you got it wrong.
Yes, I do. Let's say the V was the start of the word Very. When I hear
Uery, I know that I got it wrong. I have error correction.
Pactor just sits there trying and trying and trying and trying and trying
and trying. By the time it gets a good resend, I'm way ahead of it.
> Pactor not only knows, it automatically asks for a
>repeat and will keep on asking until it gets it right. You can not
>fool it - it either gets it perfect or not at all (see note below).
>
That's right. And if it gets hung up it can be completely lost for good.
If some CW pieces get lost, usually, sense can still be made out of what
is said. The fact is you don't need error free communication. That's
why error free modes aren't generally used in contests and DXpeditions.
It takes too long to get everything correct.
>Also, digital signal processing can be done on a Pactor signal which
>can actually pull an uncopyable signal out of the noise - one the
>human ear literally can not even hear. I'm not saying your KAM can do
>that, but it is technically possible given the proper equipment and
>software. The times they are a-changin'.
Well, I've heard this, but my KAM certainly can't do it. I know that I
can put my Timewave DSP599-zx on digital signals and pull out stuff out
of the noise that I couldn't otherwise hear, but I have a hard time
believing that anything can be pulled out BELOW a noise floor. That's
why it is called the noise floor. Maybe the DSP helps to move that
lower, but there is still a noise floor where the signal becomes
unintelligible from the back ground white nosie. The DSP can give you
some more dynamic range over the human ear. It can't work magic.
73,
Jon
KE9NA
-------------------------------------
Jon Ogden
KE9NA
http://www.qsl.net/ke9na <--- CHECK IT OUT! It's been updated!!!!!
"A life lived in fear is a life half lived."
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