[Lowfer] 74.5495 QRSS 60 as usual till at least 0600...

[Cliff Sojourner]

hi John, good points, but you are mistaken to use the actual signal 
bandwidth.  the reason is the wspr signal can be anywhere (sort of) in 
the SSB passband.  so the software does not know which 6Hz to listen 
to.  indeed at any time there are multiple 6Hz signals in the passband.  
and that is the magic.  it is not about any one signal.

Cliff K6CLS

On 2013-10-09 10:46, JD wrote:
>>>> Nothing phony about SNR being referenced to a particular bandwidth. 
>>>> Don't like the bandwidth it's referenced to just adjust with 10 log 
>>>> (BW1/BW2).
>
> True.  If you were to do that with WSPR 2, for instance, and cut the 
> reference noise bandwidth to match the actual 6 Hz signal bandwidth, 
> WSPR loses 26 db of its presumed magic right off the top.  If you 
> narrow it to the bandwidth the software needs to track the signal once 
> acquired, there go several more decibels. Which one is the most nearly 
> relevant bandwidth? Certainly not the SSB filter; you could as easily 
> use AM bandwidth and claim a few more dB.  Reporting an SNR that has 
> no relevance to the software's real ability to extract signal is 
> basically marketing hype.
>
> It's like a certain mustard I see every week at the supermarket that 
> splashes the words "40% MORE" across the bottle without even an 
> asterisk referring you to (non-existent) fine print telling you they 
> mean 40% more than their own regular size bottle sitting right next to 
> it, which just happens to sell for HALF the price. Wow, you can get 
> 40% more mustard for only twice the money?...such a deal!  When the 
> point of a number is to make people think they're getting more of 
> anything than they are, that's when I call it phony-baloney.
>
> But I'm not here to start a war between this protocol versus that 
> modulation mode, Jay.  Nor am I trying to insult the software or the 
> people who use it--merely expressing my aggravation with omnipresent 
> hype, with what I hoped was a humorous exaggeration of my own.
>
> If you'll notice my own numbers for Argo, the signal _in the detection 
> bandwidth_ was 10 or more dB above noise in nearby non-signal bins to 
> achieve that result.  Argo's not magic, either!  But I have managed to 
> get detection out of it when it only has a handful of least 
> significant bits to work with, as in this case, and far less success 
> with WSPR under similar conditions...although WSPR-X has given me more 
> promising results and better AGC tolerance than v 2.0 did.  The rule 
> of thumb thus far, however, has still been that if I can't see it with 
> reasonable consistency in Argo, it's not going to decode in WSPR 
> regardless of inflated SNR numbers.
>
> 73
> John
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