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Old March 18th 07, 08:11 PM posted to rec.radio.amateur.moderated
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Richard Crowley wrote:
OTOH, Why should we be surprised if Amateur Radio
appears to reflect the declining conduct of society in general?


Not to mention the declining technical interest
and mathematical expertise.
--
73, Cecil http://www.w5dxp.com

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Old March 18th 07, 09:43 PM posted to rec.radio.amateur.moderated
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Michael Coslo on Fri, 16 Mar 2007 09:42:30 CST wrote:

John Smith I wrote:
wrote:


However, if a new market comes forth, one composed of amateurs with
little or no knowledge of CW and only using digital voice and digital
data transmission--it would be market controlled also, and one would
suspect it would self-correct and frown on the use of the bands for
wasteful analog and cw communications.


I would disagree. Those modes are not wasteful. On the other hand, a
vision of using the HF bands for data transmission would indeed be a way
of filling up our bands pretty quickly, and for not a lot of gain. If
I'm interested in Data Transmission, I would design a system for
frequencies where there is less natural noise - VHF and up. Then
bandwidth issues would be less of a problem too.


I disagree with both of you...:-) For one thing, 300 WPM
equivalent data rate at 170 Hz "Spread" on HF does a
credible job of sending text in only a half-KHz of
bandwidth.

The presumption is that "data" somehow MUST have "perfect"
conditions to avoid errors is false. The BER or Bit Error
Rate rules the show and is a function of noise and
transmission rate (in units per second) and bandwidth.
Claude Shannon used the example of a teleprinter signal on
his seminal 1947 paper...which became boiled down to the
more familiarly-known "Shannon's Law." That was 60 years
ago and Claude wasn't considering OOK CW modes. :-)

"Data" can have a wide BER range depending on the design
of the data coding, all compared data systems having the
same data rate, signal-to-noise ratio, and channel
bandwidth. Forward Error Correction improves the BER
but isn't an absolute necessity.

An example is the ordinary modem we use on-line. If you
have a human handset as well as the modem line, try
picking up the handset and making random noise in it while
the modem is on-line. That's an extreme case, but
survivable without data disaster. You might be surprised
at how well it can survive without messing up the screen.

Let's face it, digital voice is the only way to go.


I would disagree. What I have seen in digital voice so far offers no
particular advantage over SSB, unless we are talking about digital for
it's own sake. Most schemes that I have seen have some fatal flaws, such
as the received transmission must be received in toto - IOW if you don't
catch the beginning, you don't catch anything.


I disagree with that and I have seen/heard many such systems
but - certainly - not all of them. The digitized bit stream
can be structured to enable a receiver to ID it and lock onto
it quickly. It there are lots of tones in the multiplexed
digital signal (such as with OFDM) that should be enough for
an ID and lock-in.

The solution to that
would be channelizing HF, or assigning specific frequencies to Digital
voice. In addition, unless there have been some big advances recently,


The "big advances" have already come, like in the late 1980s.
I'm mentioning a hint to the U.S. military SINCGARS in its
digital mode (with or without frequency-hopping). DSSS
essentially. Such can be slowed down or scaled to reduce its
bandwidth without disabling intelligibility (no encryption
needed or allowed by amateur regulations).

Digital voice does not have any particular bandwidth advantages.


Maybe not, but the decoded voice can be crystal clear all the
way to the threshold point (where it breaks up suddenly). It
sounds like an FM link with lots of amplitude variation, yet
there isn't any decoded speach amplitude variation.

A case in point is HDTV that we've had in this house for a
year. I've put an attenuator in the TV cable line and NOT
see a bit of difference in video nor hear any in the audio
until there is lots of attenuation reaching the threashold
of input.

Give me a Digital voice mode that I can tune across the band and pick up
a conversation at any point in the transmission, and a 1 KHz or less
bandwidth signal, and then I'll be interested.


Those are already in the works.

And of course, I'll need
to see that some other folks are buying the digital radios too, so I'll
have people to talk to.


Hmmm...what if they are thinking the same thing? :-)

Case in point: PSK31, Peter Martinez' clever brainchild was
spread all over Europe and tested by many on the Continent for
four years before it was first publicized in ARRL publications.
Not many in the USA were aware that PSK31 even existed, let
alone proven under "field conditions." Publicity caused its
spread over on this side of the pond.

PSK is too slow for
data transmission of LARGE and multi-megabyte amounts of data, end of
story.


Sorry, John, but you haven't justified any NEED for "large and
multi-megabyte amounts of data" in the amateur bands below
30 MHz. Please think harder on how much data throughput CAN
happen with existing data bandwidths and rates first. It is
quite large, although that is in subjective terms.

As for PSK, you are correct that it is too slow for data transmission.
But that little 31 baud signal was never intended for Data transmission.
It was intended for correctable text at a rate that a reasonably
proficient typist could tap away at the keyboard in real time.


Absolutely so and that was a design goal of G3PLX way back
in the begining.

Also a
mode that can be efficiently operated at QRP and lover levels. And for
that, it is an excellent mode.


Not necessarily true. PSK31 is efficient in terms of bandwidth
reduction versus data rate, still well within Shannon's Law, but
it can be used at high RF powers just as easily as low RF powers.

It seems to me to be Conventional Wisdom (a new form of "CW")
that "high power" in USA amateur bands is associated only with
OOK CW or SSB. All other modes seem to be ignored in the
literature as a general rule. That's not a technical thing,
just a subjective thing of the high-power types' desires. I've
observed that most of them are ultra-conservative (as a general
rule) insofar as mode use is concerned.

Sometimes one has to look "outside the box" of Conventional
[amateur] Wisdom to see where contemporary limits are in the
practical, working sense.

73, Len AF6AY

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Old March 18th 07, 10:08 PM posted to rec.radio.amateur.moderated
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On Mar 18, 9:22�am, "Richard Crowley" wrote:
"Steve Bonine" *wrote ...

Perhaps my impression is wrong, in which case I hope that someone will
correct me, but don't most countries treat the regulation of amateur
radio more like "here are your allocations"?


I would like to think that there are enough gentlemen in ham radio
that gentlemen's agreements and voluntary bandplans would be
sufficient. Based on what I hear on the air, that's a rather silly
hope. Nonetheless, it reflects badly on our hobby that an agency needs
to stand by with a big stick to make us do what we should be able to
do on our own.


OTOH, Why should *we be surprised if Amateur Radio
appears to reflect the declining conduct of society in general?
It *would be nice if we were better behaved, but perhaps that
is too high an expectation.

Richard Crowley KE7GKP


I can't agree with the "general societal decline" opinion.
That's been a general remark all through seven decades
of my life by each successive generation...who have all
generally flourished despite all their dire predictions.

What has been happening, to amateur radio as well as
to "general society" is CHANGE. Changes upset our
cozy concepts, those of the liked and familiar, with
strange new things, unfamiliar and untried. Changes
WILL happen and succeeding generations will consider
them as "old hat" in their day yet to come. :-)

I have to agree with Hans Brakob's "here are your
bands, have a nice day" concept (borrowed from the
late Don Stoner?). In general, that is. Practically,
there must be a middle ground in regulations. I don't
think that governmental micromanagement of mode
allocations per band is the way to go...nor should
there be so many conditional regulations on top of
those when the rest of the radio world is exploring
new things and making them work.

The FCC presently yields a lot of options to amateurs
insofar as mode use goes. If certain "gentlemen" are
inclined to stick with their familiar options at the expense
of other gentlemen, then the gentlemen ought to settle
it themselves. All the FCC can do is enforce their long-
standing "no interference with licensed users" dictum
which I think is a good thing. There's no territorial
imperative to be claimed in amateur radio spectrum
allocations, nobody "owns" certain bandspaces nor
frequencies.

As time goes on, there WILL be changes to amateur
radio bandspace divisions. There WILL be the usual
cry by the established "gentlemen" and the general
harrangues of those "gentlemen" desiring change.
Seeking a middle ground is necessary and the FCC
may have to step in (again) and change the subdivisions.
If it must, then the "gentlemen" on both sides have
failed to agree and the pessimistic view will be realized.

I'm not optimistic that all are "gentlemen" and can
settle things among themselves. I would hope they
would but I've seen a lot of generations of humans
do their thing on many varieties of activities.

73, Len AF6AY



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Old March 19th 07, 12:31 AM posted to rec.radio.amateur.moderated
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On Mar 18, 10:03?am, Steve Bonine wrote:

Because amateur radio is supposed to be self regulating.


Where is that written in the rules? I can't find it anywhere.

Perhaps my impression is wrong, in which case I hope that someone will
correct me, but don't most countries treat the regulation of amateur
radio more like "here are your allocations"?

Many countries outside the US do not have the specific
subbands-by-mode that the USA does. What they do
instead is to define the bands available to amateurs
and the modes their amateurs are allowed on each
of those bands. Where in a band that
amateurs choose to use a particular mode in a
particular band is left up to gentleman's agreements.

Before applying this idea to US amateur radio, however,
remember these points:

1) The US regulations in terms of subbands-by-mode are
not much more complex than those of any other country.
Above 30 MHz, most of the US amateur bands do not have subbands-by-
mode at all. Same for 160 meters. The bands below 30 MHz (except 30
meters) are divided into two
parts, with the lower part devoted to data modes and the upper part
devoted to voice and image. CW (Morse Code)
is allowed almost everywhere but is very rarely found in the
voice/image subbands. 30 meters does not have a voice/image subband
because it is only 50 kHz wide.

2) The number of amateurs in the USA who are authorized
to operate non-QRP HF/MF transmitters is much
greater than the number in any other country - or continent.

3) If the USA were to eliminate subbands-by-mode
completely, the real-world effect would be to allow
data modes all over the band instead of just the lower
end, and voice modes all over the band instead of just
the upper end.

I would like to think that there are enough gentlemen in ham radio that
gentlemen's agreements and voluntary bandplans would be sufficient.


So would I. But the reality may be somewhat different.

Based on what I hear on the air, that's a rather silly hope.


I think it depends where you listen.

Nonetheless, it reflects badly on our hobby that an agency needs to
stand by with a big stick to make us do what we should be able to do on
our own.


Part of the problem is lack of enforcement by FCC of
other rules of the ARS for a considerable number of
years. This situation has improved in recent years, but
it's not perfect by any means.

It should also be remembered that the requirements for
an amateur license, and the enforcement of rules, is
usually quite different in other countries. (Compare
the written-test requirements in the UK and US, for
example). There are also considerable cultural
differences.

73 de Jim, N2EY



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Old March 19th 07, 01:02 AM posted to rec.radio.amateur.moderated
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Mike Coslo wrote on Sat, 17 Mar 2007
18:32:21 CST

Often people will wonder why Hams don't run to every new mode that
comes along. Some assume that we are not adaptable as a group. I
would say it has a lot more to do with simply having someone on the
other end to talk to. We need an early following to get the ball
rolling, then there needs to be a good reason to use the mode.


Mike, you've seen enough other licensed radio amateurs by now to
understand that, technically, they are rather conservative in
adopting "new" things. My own opinion is 'uber-conservative' but
that is just personal. :-)

PUBLICITY on new things, new modes is the key to getting attention.

I'll recite that PSK31 was innovated in the UK and air-tested by
many amateurs in Europe for years before it got its first write-up
in QST for USA amateur radio consumption. Why? I don't know for
sure but I will start shining some light on editors and frequent
contributors to QST. I think that they were honestly unaware of
it. It isn't like they are unaware of the RSGB periodicals.

Another case is Mike Gingell's polyphase audio network. Mike, now
a resident and ham licensee in the USA, did his PhD dissertation
on that network. It enabled four quadrature-phased audio outputs
with excellent phasing accuracy using lower-tolerance parts. It
was publicized in Pat Hawker's column in Radio Communication
magazine in 1973, the experimenter trying it out was Peter Martinez,
G3PLX, the guy who would come up with PSK31 later. European hams
have been trying it out for SSB modulation and demodulation ever
since; makes for a smaller SSB sub-assembly. It got some attention
from 1974 onwards over here, but not a lot. It even got lots of
attention in the IEEE Communications magazine for frequency-
multiplexed telephony but that was displaced by up and coming
digital time-multiplexing right afterwards. Long-distance
wired telephony was the first user of SSB, BTW. :-)

Conservative USA amateurs tend to stay with what they know and
learned when young...except for the few who actually work with
higher-tech modes for a living...and some of those tend to
"relax" with tried-and-true modes off-work. That re-enforces
the conservative approach to "state of the Art" advancement.

Part of that conservatism may be the "made only in America"
thinking. Look at D-Star that's been getting publicity by
the Big3 amateur radio makers of Japan. D-Star has been
around for three years, innovated by the JARL. It seems to be
very good in providing flexibility to connect with the Internet
through VHF-UHF repeaters. [I got a demo of it just recently]
No, it's not a "practical" thing on "the bands" (what so many
amateurs call the HF bands) but it seems to work just dandy
on handling both voice and data together on VHF-UHF.

The
difference between say Spread spectrum and say PSK31 is that PSK
apparently serves some purpose for a growing number of Hams, and SS
doesn't.


Ummm...PSK31 was originally designed for HF ham bands and was
deliberately narrow-band. Spread-Spectrum modes are for wider
bandwidths available only on UHF and up in frequency. DSSS is
already a proven winner in multiple-user WLANs in other radio
services (no discernable interference or catastrophic BERs) but
is good only for LOS radio paths. As a result, it will see
application only in more densely populated urban areas in the
USA. Conservative radio amateurs here stay on HF and all its
narrowband limitations.

Now, it MIGHT be that FHSS could be adapted to HF, even if only
to 10m with that band's 1.7 MHz total bandwidth. That is uncertain
since it absolutely requires a higher-accuracy timebase than is
found in most upscale HF+ transceivers. [think timing update
and correction via GPS] It will NOT be "tunable" like the older
analog modes, at least that I can envision. Neither will it cause
much interference to those legacy-mode users already there.
However, it does have a potential of getting more users in the
same bandwidth for higher throughput than is possible with analog
modes.

Many, many things are possible, even the digital voice and music
on HF now being used for BC purposes. But, that's a niche thing
and only proves the mode is practical and viable. On the other
hand, there's some "comfort" in staying "establishment," of not
having to spend time finding out how those new-fangled things
work; i.e., survivalist conservatism. :-)

73, Len AF6AY

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Old March 19th 07, 02:17 AM posted to rec.radio.amateur.moderated
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On Sat, 17 Mar 2007 14:37:57 CST, "Dee Flint"
wrote:

Another thing to keep in mind that as our infrastructure becomes stronger,
hams will only really be needed in the absolutely worst disasters.


There will always be a need because no matter how strong the
infrastructure is, situations will arise that exceed that capability.
Design of public safety communication systems is the specialty of my
engineering firm and I'm all too painfully aware of the real-world
limitations

Example: One of our med center nets is an inter-hospital net that
carries traffic on bed availability, staff availability, and medical
supply status and need to and from the Metro Regional Hospital
dispatch, the "czar" of inter-hospital operation, which directs
ambulances and supply resources to the available facilities. It is
currently staffed by personnel located in another neighboring med
center. The VHF simplex and repeater ham portion (ham stations
located in the Emergency Departments of all the local hospitals) backs
up a system which is a user group on the City of Portland's 800 MHz
trunked system. When things get tight, the trunked system will be
overloaded with police and fire operations, assuming that the system
survives at all. That's where the hams come in.
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest

Beaverton (Washington County) Oregon

e-mail: k2asp [at] arrl [dot] net

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Old March 19th 07, 02:47 AM posted to rec.radio.amateur.moderated
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On Sun, 18 Mar 2007 11:48:45 CST, wrote:

Thank you, Steve. Your point is very real, and the historic
'solution' has been for the government (FCC) to impose regulatory
handcuffs on the market-based arbitration of that tension. This has
the practical effect of total regulatory favor of the legacy use over
the exploration of new ideas.


A (sad) example of the interaction of the Amateur Radio Service with
the :"marketplace" can be shown in the loss of the 220-222 MHz band.
The FCC's expectation was that it was going to be dedicated to a small
number of wide-area commercial networks using Amplitude Compandered
Side Band (ACSB), a system developed by "basement" tinkerers for
commercial use using amateur frequencies because they couldn't get a
license for commercial development (*)

It never happened. ACSB never worked, and the commercial equipment
manufacturers never produced any sizeable amount of equipment for that
band.

Did we get the frequencies back? In your dreams.

(*) I won't get into the personalities involved in the ACSB fiasco or
of the slicing of the 220 MHz band - it's Sunday and I can't get
enough blood pressure medicine if I do.... Suffice it to say that
despite urban legend, UPS was not a real player in that mess.
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest

Beaverton (Washington County) Oregon

e-mail: k2asp [at] arrl [dot] net

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