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[AMPS] ARRL and QST (and CW Relevance)

To: <amps@contesting.com>
Subject: [AMPS] ARRL and QST (and CW Relevance)
From: docdc@ix.netcom.com (docdc@ix.netcom.com)
Date: Sat, 30 Jan 1999 00:10:26 -0600 (CST)
On 01/29/99 19:23:17 you wrote:
>
>
>>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

Jon, you hit the nail on the head. I keep hearing about digital mode prowess, 
and after 
investing a ton of money in it, it sure doesn't beat CW. Lot's of people told 
me it would, but I 
have yet to see it. 

In my opinion, there is nothing that compares to the human brain for error 
correction.

Dale
KC8FAQ

"Digital-Another Urban Legend."



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