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July 17th 03, 05:45 PM

(Brian Kelly) wrote in message . com...
"Carl R. Stevenson" wrote in message ...
"Brian Kelly" wrote in message
The "strawman designs" that Gary and I postulated did NOT contemplate
the use of SS across the whole band as an "underlay." The modulation was
completely different, with a fair amount of coding.

That's not my recollection at all but for absolute certain any type of
HF SS would require some bandwidth far in excess of the bandwidths
currently permissable under the regs or acceptable by the users of the
so-called legacy modes on HF. The inherent bandwidth characteristic of
SS has made it destructively non-compatible with the modes currently
in use in HF ham bands. Ain't gonna happen in our lifetimes, ham HF SS
is a non-sequiter.

The really important question is simply "how would such a system be
implemented?" IOW, who is going to develop it, set the standards,
build the equipment, put the stations on the air, etc.? I can imagine
all sorts of really neat systems I'd like to see (say, a
highspeed/"wideband" microwave digital network linking major cities
via ham radio, over which hams could have all sorts of QSOs through
local portals) but who is gonna put up the bux and do the work? I
don't see Carl, Vipul, Gary or anybody else stepping up to take on
even a piece of it.

all sorts of simulated channel impairments into the system to make
copying
as hard as you want ... without having to trash the underlying, reliable
communications system." Still rejected.)

Exactly and none of it flew then and it never will.

Why?

See above. Somebody has to actually DO it. Not just talk about it.

Lookit G3PLX and PSK-31. Guy developed an idea, worked on it for
years, recruited knowledgeable hams around the world for tests. One of
whom is a really sharp local Ph.D EE ham known to both W3RV and me.
When the bugs were worked out, they just gave it away to the ham
community - free software, step-by-step articles on how to connect
your lapper to your rig, excellent articles on how it works and why.

Once it was public, other hams got involved in software improvements,
purpose-built rigs like the Warbler, demos, more articles, books, etc.
Now mainstream "PSK-31 ready" rigs are beginning to show up on the
amateur market.

How many years and how many hours and how many
dollars/pounds/lira/shekels, all of it donated, went into the
development of PSK-31?

... if it looks to the user EXACTLY as "traditional Morse" one would
not be able to tell the difference (and therefore should have no logical,
rational reason for rejecting it).

Your term IF is the Achilles heel of your whole argument.

Right. There's no way it will look exactly like the real thing.

Kinda like the idea of having athletes all over the world run the
Boston Marathon on computerized treadmills surrounded by
high-definition TVs, with automated weather simulation (heat, rain,
wind, etc.) They're all covering the same distance under the same
conditions, right? No need to close all those roads and deal with all
the headaches of a real road race, right? And lots more people will be
able to participate, without all the hassle of getting to Boston and
back, qualifying for the race, etc.

We've been
down this road, i.e., the problem with logical/rational being the
primanry drivers in ham radio. Ham radio is not a commercial service
where logic is the driver. The standard issue ham is into ham radio
for it's recreational value and the rest flows from there.

I gotta disagree here. Ham radio is driven by as much "logic" as any
other radio service - often much more. But the driving forces are
different. Take military comms - they want very high accuracy, very
high security, very high speed, very high reliability. Size, weight
and power consumption considerations vary all over the place from
"doesn't matter too much" to "gotta be kept to absolute minimum". Cost
and complexity are way, way, way down on the list. "Fun" isn't on the
list at all. Radio is just a comms tool to the military folks - if
something 'better' comes along tomorrow, they'll be all over it.

Which is where those surplus 55-75 foot tubular-section towers we've
used on FD came from. They were originally meant for terrestrial
microwave. You know what they cost the ham who wants one. You don't
wanna know what Uncle paid for 'em. Ya think Uncle really cared what
the resale value of those towers would be?

For hams, the top of the list is almost always "FUN". High on the list
are cost, size, complexity, required maintenance, ease of use, useful
life, resale value, etc. But FUN is the biggie, and if it ain't fun
according to the perception of the "user", there ain't gonna be no
users. And each user has his/her own definition of "FUN".

Pretty logical system, really.

Heck, the whole anti-code-test argument comes down to "why require
folks to learn something that they don't think will be fun to do?" and
"the people who see it as fun will learn it without a test".

they're neat electronic ping-pong games but IT AIN'T FRIGGING RADIO.
Nobody is gonna go play electronic ping-pong so that you and Coffman
can play band edge to band edge.

I *was* talking about RADIO ... a system that would communicate over
distances via radio ... just more reliably ... and THEN adding the
impariments
("challenge") at the receiving end to satisfy those who "like to dig the
weak ones out of the noise/QRM."

And by doing so you miss the whole point of what makes it fun in the
first place: the fact that it's real and not a simulation.

Then you better find a like-minded programmer who has extensive
real-world actual experience with weak-signal DXing and contesting CW
and otherwise to write the code. You sure as hell are not qualified to
do that.

I dunno, maybe Carl and Gary are able to do it. But will they? Don't
hold yer breath. Classic 'tie the bell on the cat' situation. See
above PSK-31 story.

You're snapping around the edges of needing AI to pull off any such
code. We all know how easy that is (?!). IBM has a well-funded crew of
their comp sci & math geniuses and a mainfarme dedicated to
periodically trying to beat one human chess player's brain. And chess
is just a two-dimensional board game with rigid rules of play which
allows large chunks of time to make the decisions on each move.

The system they use also "cheats" in a way, in that it has an enormous
library of games that have been played before accessible. It can look
at a particular board position and check if that particular position
ever came up in any recorded game before, then see what was done and
how it came out.

Does the computer have "fun" playing? Just ask it.

HF CW
contesting in particular has more dimensions than I can even start to
count and decsions are routinely made several times a second. Just for
openers. How ya gonna do it Carl? A bit of C++ and VB in a ham shack
PC? Yeah, right. Not even a decent pipe dream.

Heck, just network everybody's computer together and we can run a
virtual contest whenever we want. No need for towers, amplifiers, etc.
Set up any virtual station you want.

transmit data reliably over transcontinental distances ... with power
outputs on the order of 10 mW ... as an "underlay" to existing services
that don't even notice that they are there.

Do the services who "don't know they are there" know what to look for?
Or do they just think their noise floor is a little higher?

Times how many stations?

Quite a few, but to be honest I don't know the exact number (and if I
did, I couldn't say).

Bullet = Ducked

Speaking of which, consider how many CW QSOs at 40 wpm could fit in
that 150 kHz of 20 meters. At least 300 without interference, meaning
at least 600 hams on the air in that space without frequency re-use.
And that's using really simple, dirt-cheap equipment like the receiver
I built almost 30 years ago whose pictures are now on the HBR site.

I notice that TAPR has given up trying to get spread spectrum on the
air. Nobody in TAPR cares enough about SS to work thru the bugs.
There's a loud statement about ham SS.

IMHO, TAPR's SS effort was doomed from the start by being overly
complex.

Complex compared to what? More complex than a PC? Or was there too
much talk and too little action?

Maybe it was a solution in search of a problem.

73 de Jim, N2EY