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  #81   Report Post  
Old March 28th 08, 10:46 PM posted to rec.radio.amateur.moderated
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First recorded activity by RadioBanter: Jun 2007
Posts: 50
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(Dave Platt) wrote:

I hope you'll pardon me when I ask "Which deity spoke to you and laid
down those particular points of Absolute Truth?". What's all this "We
need to" and "no more and no less" and "xxx is better" and "yyy is
inferior" and "... is also considered better"?

If you're willing to state those as _your_ personal opinions of the
basis on which two partially-competing methods of encoding and
communicating _should_ be compared (and that no other criteria need
apply), I have no objection at all.

I do, however, object in principle to the idea that these are the
highest (or only) criteria, or that they're somehow sacred.



I think of them as matters of economics and practical reality. To
wit: it should be obvious that we cannot have every possible mode
available on every band. Some limits must be imposed on the number of
modes and the way in which they share limited bandwidth. This is one of
the reasons why the FCC exists. This is one of the (ostensible) reasons
why digital modes were not allowed for many years.


And, I also object to the idea (which I think is implied by the tone
of your other messages - please correct me if I'm wrong) that the
choice of communication methods is somehow exclusive... that the fact
that a method which is superior (by your criteria, perhaps) means that
other methods that you find inferior should be wiped out or
abandoned... or that people who prefer to use the other methods are
somehow responsible for Holding Back The True Progress.

My own perspective is that people may have *many* criteria for chosing
a means of communication (by radio or otherwise). Bandwidth, or
bandwidth*reliability is not the sole criterion that people use, in
practice, nor do I think there's any reason that it should be. Life
is full of tradeoffs between different criteria - information
bandwidth per Hz of spectrum, robustness of encoding, suitability for
multi-point communication, resistance to different sorts of
interference, cost of equipment, availability of equipment, and so
forth. I communicate with my wife by voice, by email, by telephone,
by scribbling half-illegible notes on scraps of paper, and by bringing
home flowers... different methods, for different types of information-
passing under varying conditions.



Again, if you can't fit every possible mode onto a given band (by the
way, every possible mode means exactly that, not just modes that are
commonly used by hams - otherwise, we would have APCO 25, in addition to
DV, to give just one example). Therefore, we must prioritize; some modes
will be authorized, while some other modes will be excluded. This goes
back to my claim that it is a matter of economics; it represents a
managed resource (a limited "supply") in the face of potentially
unlimited demand. It is from that perspective that I claim that old time
Morse zealots are impeding progress and are attempting to arrogate to
themselves a finite public good, much like cattlemen grazing their cows
on public grasslands while excluding others from using those public
lands for other purposes.


In commercial communications and public-safety, bandwidth (or payload)
and reliability and cost all play a big factor. In military
communications, reliability and security seem big, bandwidth is
important, and cost (of equipment at least) tends to take a back seat.

Ham radio is a much more diverse motivation-space. Some people
optimize their operations as for public safety and commercial (the
EMCOM folks), others for "most distance per watt" or "per dollar spent
on the radio" (QRP folks, homebrewers, and other experimenters),
others for portability, others for plain ordinary fun (according to
their own definition of fun... for some folks, using single-frequency
crystal-oscillator transmitters is just what gets their rocks off :-)

There's plenty of room in ham radio for different modes of operation.
Saying that we all *have* to abandon Morse (or SSB, or voice, or AM,
or...) and strap computers to all of our rigs, in order to encourage
experimentation and use with newer modes, is really missing the
point... it's implicitly denying a large percentage of hams the right
to explore those aspects of ham radio that *they* find interesting and
worthwhile.

If we were all being paid to do all of this stuff, then the people
paying us would perhaps have the right to set our agendas. We aren't
(and by the rules of the game, cannot be... at least, not here in the
US) and so we get to set our own priorities, operating-mode and
otherwise.



Considering the small, aggregate size of the HF bands, can you offer
some suggestions as to how many modes can plausibly 'share the road?'
What modes must be forbidden so that the modes that you like can be
allowed? If you say that there are none, then perhaps we can have APCO
25, DV and DD on HF? What do you say to the hams who claim that AM
shouldn't be used on HF, because it uses to much bandwidth?


[And, for the record - I operate CW only rarely, and have enjoyed
experimenting with packet and the newer digital modes quite a bit.]


--
Klystron


  #82   Report Post  
Old March 29th 08, 01:46 AM posted to rec.radio.amateur.moderated
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First recorded activity by RadioBanter: Jul 2006
Posts: 877
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On Mar 28, 4:46�pm, Klystron wrote:
(Dave Platt) wrote:

I do, however, object in principle to the idea that these are the
highest (or only) criteria, or that they're somehow sacred. �


� �I think of them as matters of economics and practical r

eality. To
wit: it should be obvious that we cannot have every possible mode
available on every band.


Well, not every *possible* mode.

Some limits must be imposed on the number of
modes and the way in which they share limited bandwidth. This is one of

the reasons why the FCC exists.

Of course. But there are other factors, such as how popular a mode is,
how much bandwidth it occupies, how it is implemented, etc.

This is one of the (ostensible) reasons
why digital modes were not allowed for many years.


Please elaborate, particularly on the dates and where you got thise
idea.

The information I have seen says that the main reason FCC limited the
modes amateurs could use was that FCC has to be able to monitor
amateur transmissions. So if they allowed hams to use a new mode,
their monitoring stations had to be able to decode it.

45.45 baud 5 level Baudot RTTY was authorized for amateurs in the USA
about 1948. Analog SSTV (an image mode) followed in the very early
1960s.

In the late 1970s-early 1980s, new monitoring equipment made it
possible for FCC to decode lots of modes, so US amateurs were
authorized to use ASCII RTTY, AMTOR, packet, and lots of other modes.
We're talking 20-25 years.

Of course not all modes are well-adapted to all bands. HF packet as
used by amateurs turned out to be a bit of a bust, due to being ill-
suited to HF propagation. PSK31, OTOH, has been a big hit.

The biggest impediment to digital modes in the ARS, IMHO, is the cost
of implementing them. Inexpensive PCs and "soundcard modes" have
changed all that.

And, I also object to the idea (which I think is implied by the tone
of your other messages - please correct me if I'm wrong) that
the
choice of communication methods is somehow exclusive...
that the fact
that a method which is superior (by your criteria, perhaps)
means that
other methods that you find inferior should be wiped out or
abandoned... or that people who prefer to use the other
methods are
somehow responsible for Holding Back The True Progress.


My own perspective is that people may have *many* criteria
for chosing
a means of communication (by radio or otherwise). �
Bandwidth, or
bandwidth*reliability is not the sole criterion that people use, in
practice, nor do I think there's any reason that it should be. �

Life
is full of tradeoffs between different criteria - information
bandwidth per Hz of spectrum, robustness of encoding,
suitability for
multi-point communication, resistance to different sorts of
interference, cost of equipment, availability of equipment,
and so
forth. �I communicate with my wife by voice, by email, by
telephone,
by scribbling half-illegible notes on scraps of paper,
and by bringing
home flowers... different methods, for different
types of information-
passing under varying conditions.


� �Again, if you can't fit every possible mode onto a give

n
band (by the
way, every possible mode means exactly that,
not just modes that are
commonly used by hams - otherwise, we would have APCO 25,
in addition to
DV, to give just one example). Therefore, we must prioritize;
some modes
will be authorized, while some other modes will be excluded.
This goes
back to my claim that it is a matter of economics; it represents a
managed resource (a limited "supply") in the face of potentially
unlimited demand.


With all due respect, I think you are avoiding the question. Under
current FCC rules, almost any conceivable mode can be used on the
amateur bands if it is properly documented, does not involve
encryption, and is reasonably spectrum-efficient.

Look at how PSK31 came to amateur radio for an example. It was
developed by hams, not manufacturers. It's relatively easy to
implement without a big investment of special equipment, it's well-
adapted to HF conditions and spectrum-efficient. Most of all, a
considerable number of hams find it to be fun.

It is from that perspective that I claim that old time
Morse zealots are impeding progress and are attempting to
arrogate to
themselves a finite public good, much like cattlemen grazing
their cows
on public grasslands while excluding others from using
those public
lands for other purposes.


How have "Morse zealots" done what you claim? In the US regulations,
there are no Morse-code-only segments of the HF bands - all are shared
with either data modes or voice modes. Every Hz. And it's been that
way at least 46 years.

Except for 2.5% of 6 and 2 meters, all of VHF/UHF and 160 are wide
open to all authorized modes for the various bands.

How are Morse-Code-using hams doing what you claim?

The cows-grazing-on-public-land analogy isn't really valid, because
amateur radio isn't a commercial venture, nor does the use of one mode
damage the band for use by others at a later time.

Try this one:

The amateur bands are like a public park system. Some are small, some
are large, some easily accessible, some remote. Depending on their
characteristics, different parks/bands are used for different
activities at different times. The question is how to best allocate
the resources to accomodate those who want to use them.

In commercial communications and public-safety,
bandwidth (or payload)
and reliability and cost all play a big factor. �In military
communications, reliability and security seem big, bandwidth is
important, and cost (of equipment at least) tends
to take a back seat.


Ham radio is a much more diverse motivation-space.
�Some people
optimize their operations as for public safety and
commercial (the
EMCOM folks), others for "most distance per watt"
or "per dollar spent
on the radio" (QRP folks, homebrewers, and other
experimenters),
others for portability, others for plain ordinary fun (according to
their own definition of fun... for some folks,
using single-frequency
crystal-oscillator transmitters is just what gets their rocks off :-)


Nice pun!

There's plenty of room in ham radio for different modes of
operation.
Saying that we all *have* to abandon Morse (or SSB, or
voice, or AM,
or...) and strap computers to all of our rigs, in order to
encourage
experimentation and use with newer modes, is really missing the
point... it's implicitly denying a large percentage of hams
the right
to explore those aspects of ham radio that *they*
find interesting and worthwhile.


That's exactly the point. Well worth repeating!

If we were all being paid to do all of this stuff, then the people
paying us would perhaps have the right to set our
agendas. �We aren't
(and by the rules of the game, cannot be... at least,
not here in the
US) and so we get to set our own priorities, operating-mode and
otherwise.


� �Considering the small, aggregate size of the HF bands,
can you offer
some suggestions as to how many modes can plausibly
'share the road?'


That depends on the modes and their characteristics. For example, it's
not a good idea to allow 30 kHz FM voice on 40 meters, because that
band is only 300 kHz wide, but the same mode is fine for VHF/UHF
bands.

What modes must be forbidden so that the modes that
you like can be allowed?


If you say that there are none, then perhaps we can
have APCO 25, DV and DD on HF?


If they meet the criteria of not being encrypted, being suitable
for HF use, and being reasonably spectrum-efficient, why not?

As long as they are grouped with similar modes, what's the problem?

What do you say to the hams who claim that AM
shouldn't be used on HF, because it uses to much bandwidth?


That depends on how "too much bandwidth" is defined. Certainly
transmitting hi-fi AM that's 10-15 kHz wide on a busy HF band is
spectrum-inefficient and inconsiderate. OTOH, good-quality voice AM
can be had in 6 kHz or so, and when a band is not too busy, why not
use it? Similar

It seems odd that "Morse zealots", whose favorite mode uses only a few
hundred Hz at most, are being held responsible for "impeding
progress", when most of the HF amateur bandspace in the US are
allocated to voice modes that take up much more spectrum.

Should hams stop using Morse Code? Or any other mode they now use?

73 de Jim, N2EY

  #83   Report Post  
Old March 29th 08, 04:25 AM posted to rec.radio.amateur.moderated
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First recorded activity by RadioBanter: Jul 2006
Posts: 464
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In article ,
Klystron wrote:

I think of them as matters of economics and practical reality. To
wit: it should be obvious that we cannot have every possible mode
available on every band.


We can't have all of the modes, simultaneously, with an unlimited
number of users, on every band band, at the same time. Bandwidth is
limited - granted.

It does not follow from that, that we must be limited to a
strictly-enumerated set of modes at all times. The FCC used to assert
that this was the case, but has eliminated many of those constraints
in favor of an approach which favors more experimentation and
development.

Some limits must be imposed on the number of
modes and the way in which they share limited bandwidth.


I agree that a policy that users of the band must share bandwidth in a
reasonable and respectful way, is reasonable and proper.

I do *not* agree that this necessitates that only a specific set of
modes be allowed.

Again, if you can't fit every possible mode onto a given band (by the
way, every possible mode means exactly that, not just modes that are
commonly used by hams - otherwise, we would have APCO 25, in addition to
DV, to give just one example). Therefore, we must prioritize; some modes
will be authorized, while some other modes will be excluded. This goes
back to my claim that it is a matter of economics; it represents a
managed resource (a limited "supply") in the face of potentially
unlimited demand. It is from that perspective that I claim that old time
Morse zealots are impeding progress and are attempting to arrogate to
themselves a finite public good, much like cattlemen grazing their cows
on public grasslands while excluding others from using those public
lands for other purposes.


The portion of the band which is restricted to CW-only by the FCC is
*tiny* - small portions of the 2- and 6-meter bands, plus a portion of
80 which is CW-only for Novices and Technicians but not for anyone else.

Almost all of the non-phone portions of the band are *already* open to
various digital modulations (per the FCC regs and per the ARRL
bandplans and gentlepersons' agreements), and are quite extensively
used in that fashion today.

From where I sit out here in the cheap seats, your own attitude

strikes me as more zealous, and less willing to cooperate and share,
than what I observe in the people I know who operate a lot of CW.

Considering the small, aggregate size of the HF bands, can you offer
some suggestions as to how many modes can plausibly 'share the road?'


I don't think it's a question which can meaningfully be measured in
"number of modes". Some modes co-exist well, others do not.

I think it's a question of the number of _users_ of the band, at any
given time, and the type and quality of the conversations that they
can carry on.

What modes must be forbidden so that the modes that you like can be
allowed?


Well, I tend to agree with the FCC that broad-spectrum audio (e.g. SSB
with a DC-to-10-kHz bandwidth, or [worse] AM with a similar passband)
is excessively wide - it's using more bandwidth than is reasonable for
the conversation in question.

If you say that there are none, then perhaps we can have APCO
25, DV and DD on HF? What do you say to the hams who claim that AM
shouldn't be used on HF, because it uses to much bandwidth?


I think there's room for AM, and that SSB is more bandwidth-efficient,
and that the de facto practice of having AM operators voluntarily hang
out in a sub-portion of the HF band works pretty well.

I guess I just don't see why you're so intent on suppressing a mode of
operation which allows quite a lot of individual operators to carry on
multiple independent conversations within a limited bandwidth, at one
of the lowest potential equipment costs per operator of any mode.

Granted, other modes may get more *total* data traffic through the
same amount of spectrum width... but these modes tend to use more
spectrum width per conversation/session, and you end up with less
individual users of the band at any given time.

Applying a purely "economic" model to the ham spectrum (i.e. most
traffic per available Hz of bandwidth) rather misses the point, I
think, because it completely discounts all of the other values
(personal enjoyment, learning, development of personal skills and
knowledge) in ham radio. Ham radio is *NOT* a commercial service with
just a single agenda.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!



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