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Re: [TowerTalk] The bad news

To: <n8de@thepoint.net>, <towertalk@contesting.com>
Subject: Re: [TowerTalk] The bad news
From: "Jim Jarvis" <jimjarvis@comcast.net>
Reply-to: jimjarvis@ieee.org
Date: Thu, 21 Jul 2005 08:46:21 -0400
List-post: <mailto:towertalk@contesting.com>
Don,

As I said privately to Tom, we're going to have to agree
to disagree, on both my major points.

There have been dumbasses on the air for as long as I've
been a ham.  They passed the code tests.  I know some very
bright and capable people who consider morse to be a ridiculous
waste of time...and who aren't intrigued by "can you hear me now?"
communications...they've explored ham radio, and walked away from
it, as being too much trouble for too little payback.  I think we've
kept out more smart guys than we've kept in, but there's no way to
prove either argument, except by trying a change.

As for synchronized digital modes being able to detect weaker
signals than cw...consider two things:

1)  jt44 has enabled modest 2m stations to conduct moonbounce work,
whereas CW requires a kw and a monster array.

2)  psk31, in a 50Hz bandwidth in my 756pro, can produce useful copy
on signals which I not only can't see in the waterfall, I can't hear.
Within that same bandwidth, switching to cw...I STILL couldn't hear the
signal.  Hardly definitive, but strongly suggestive.

Let's not prolong the debate on the reflector...it was off-topic to start
with, and I shouldn't have stirred the pot.  (The devil made me do it!)

n2ea


-----Original Message-----
From: Don Havlicek [mailto:n8de@thepoint.net]
Sent: Thursday, July 21, 2005 08:25
To: Tom Rauch
Cc: jimjarvis@ieee.org; towertalk@contesting.com
Subject: Re: [TowerTalk] The bad news


Tom,
I definitely agree and couldn't have said it any better than you did!
Congratulations on putting my exact thoughts into your tome.
Don
N8DE

Tom Rauch wrote:
>>However, the evidence is that narrowband digital  (psk31)
>
> will
>
>>copy at signal levels you cannot hear...making CW less
>
> than the
>
>>ultimate weak signal mode...although certainly simpler.
>
>
> Sorry Jim, that just isn't true. That rumor probably comes
> from the fact many people using PSK don't understand radio
> systems very well.
>
> People listen to a receiver on 2-3kHz bandwidth and can't
> sort the tone from noise. They then go away enamored with
> PSK, thinking it is a magical answer to all things weak.
>
> What they forget is the PSK system "listens" through a
> narrow filter of less than 100Hz. If they knew CW and
> listened to the CW or PSK tone with the same bandwidth and
> the same slow sending rate as PSK they would find a good CW
> op can copy as well as or better than a PSK signal will
> print. The balance really tips in favor of CW when you
> consider transmitter energy used and dynamic range of the
> system.
>
> PSK has horrid dynamic range, that's why PSK operators are
> constantly at each other's throats about antennas and power.
> They demand everyone run low power and often suggest people
> use an intentionally poor antenna to keep signal levels
> down. The reason they make those demands is PSK is
> inherently a very poor system for dynamic range. PSK depends
> on distortion-free operation of every mixer and gain block
> between a D to A converter in the sound card at the
> transmitter and an A to D converter in the sound card at the
> receiver.
>
> I think what Hams miss is the dumbing down we are going
> through, and make no mistake about it Ham radio is dumbing
> down, is a social change. Societies eventually peak
> technically. They lose basic skills because those basic
> skills are replaced by "advanced" technology that springs
> from the basic skills. That's where we are at.
>
> Get used to it. Basic skills that are the root of our
> technical advancement are going away. People are getting
> lazy, and most people don't want to learn technical things
> just for the sake of enjoying learning. The fashionable
> thing is to make an excuse why basic skills aren't useful.
>
> 73 Tom
>
> _______________________________________________
>
> See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>




_______________________________________________

See: http://www.mscomputer.com  for "Self Supporting Towers", "Wireless Weather 
Stations", and lot's more.  Call Toll Free, 1-800-333-9041 with any questions 
and ask for Sherman, W2FLA.

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