This all reminds me of the claims made about Fractal antennas.
Lots of articles were written about how "superior" fractal
antennas were compared with traditional methods of loading.
Oddly enough however, the only article I have ever seen that
made actual apples to apples comparisons between Fractal
and non-fractal loading methods actually showed that Fractals
elements were either the same or in some cases worse than
the non self-similar elements. Same thing goes with PSK31.
People listen to their audio outputs in a 3KHz
bandwidth and then are amazed when the soundcard can decode
signals they can't hear - well duh! A PSK31 signal is about 50
Hz wide, and so is the matched filter in the sound card - thats
about 17dB of additional SNR - no magic. Also, try cranking
up your Alpha to 1.5 KW output while running
PSK31. That is why everyone runs 5 watts, because that's how
far you'll need to back off your MIC gain before people stop
complaining about your IMD levels.
Somebody needs to run actuals link tests on a calibrated test bed
in various noise environments (impulse, gaussian, lightning static)
comparing CW and PSK31 before these assertions can be
verified. Maybe PSK31 does have some advantage, but I have
yet to see anything but anecdotal claims. Sounds like a good
paper for QEX magazine.
73 de Mike, W4EF.............................
----- Original Message -----
From: "Bill Tippett" <btippett@alum.mit.edu>
To: <cq-contest@contesting.com>
Sent: Friday, July 19, 2002 2:55 AM
Subject: Re: [CQ-Contest] CW or SSB FCC says neither.
> K4JRB wrote:
> >The new FCC Chairman told a group of hams that its time for amateurs
> to move to the new modes and leave what he considers are obsolete modes.
>
> And exactly what are his credentials? Do you think he has any
> idea he knows what he is talking about? I don't.
>
> http://www.fcc.gov/commissioners/powell/mkp_biography.html
>
> Perhaps he would like to demonstrate digital modes are superior by
> comparing contest results for existing contests. Here are high-claimed
> CQ/RJ WW RTTY scores from last fall's contest:
>
> http://lists.contesting.com/pipermail/3830/2001-October/029841.html
>
> The highest number of contacts made by any single op was 2461 QSO's
> which is not even close to the typical CW or SSB SOAB scores. I even
> made more than that myself on 10 meters alone! Isn't it about time
> we stop taking these "expert" claims at face value and do a reality
> check with the brain God has given us?
>
> >He said (and ARRL agrees) that a mode such as PSK31 is superior to CW
> in weak signal environments.
>
> Then I have a challenge for CQ Magazine Dave. Replace the CQ
> 160 SSB contest (where SSB has already been proven inferior to CW) with
> the CQ 160 PSK31 contest. Let's just see if Chariman Powell and ARRL's
> claims are true rather than taking them at face value.
>
> >Amateurs are working each other with QRP where signals are below the
noise
> threshold. Listen to the speaker and there is nothing!
>
> Sure some of the computer-to-computer modes (PSK31, WSJT, QRSS)
> can extract signals below the noise level, but how quickly do you think
> they could make contacts? A QRSS contest would be a real blast to hear
> at ~0.8 words per hour!
>
> >The FCC Chairman also stated that CW is no longer in use in DOD
applications
> and is rapidly disappearing in Commercial Marine communications.
>
> So what? Most of the human element is being removed from DOD
> applications (pilots, operators, etc.) My only question is "What do
> you do when the computer or GPS fails?" I suppose whe have also
> stopped teaching Commercial Marine captains how to use sextants, but
> I wouldn't want to go to sea with one who didn't have one and know how
> to use it. Rather than making ourselves totally dependent on technology
> (which I am a firm believer in BTW), I would hope we are teaching our
> military "what to do when the computer breaks".
>
> >So are we getting in disfavor with the FCC by sticking to CW or SSB?
>
> I think it's time we stopped accepting some of the groundless
> assertions we are getting from the FCC and ARRL. If we really believe
> some digital mode is superior, let's put it to the (con)test, which is
> the ultimate test of communicatins under extreme conditions. I have
> yet to see any digital mode that would even come close but I would
> gladly change my opinion if factually proven otherwise. Opinions from
> FCC Chairman Powell just won't do it for me.
>
> 73, Bill W4ZV
>
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