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  #11   Report Post  
Old March 23rd 08, 08:33 PM posted to rec.radio.amateur.moderated
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Paul W. Schleck " wrote:
Klystron writes:


It still seems like an awfully slow data rate. I have seen people
throw 14400 Baud modems in the garbage because they considered them to
be so slow as to be worthless. A data rate of 42 bps is about 3 orders
of magnitude slower than that.



Many types of communications vary over many orders of magnitude of
information rate, yet are considered useful and up-to-date.

For example, the Casio WaveCeptor on my wrist:

http://www.eham.net/reviews/detail/2497

receives a ~ 1 Baud Pulse Position Modulated (PPM) signal from radio
station WWVB in Fort Collins, Colorado, which transmits on 60 kHz. It
takes about a minute to send the complete time code to synchronize my
watch. Slow? Yes. Useful? Yes, very much so, especially when
considering the coverage and reliability that can be obtained from such
a low-bandwidth, groundwave-propagated, Very Low Frequency (VLF) signal.
[...]



In your model, only a single axis of data is transmitted - the time
of day. That seems like a great deal of infrastructure and energy
consumption to transmit a single data quantity. The equivalent
infrastructure for weather transmission (marine and air) is even more
elaborate and expensive. Can you see that is an outrageously inefficient
way to distribute a small quantity of information?


One of the most current and widely used communications technologies
among young people is cellular telephone text messaging:

http://en.wikipedia.org/wiki/Text_messaging

(sometimes also called "Short Messaging System" or SMS)

According to this recent demonstration on the Tonight Show with Jay
Leno:

http://www.youtube.com/watch?v=AhsSgcsTMd4

the realizable data rates are comparable in order of magnitude to that
of fast Morse code that can be sent and received by human operators.
Just try telling a teenager with an SMS-capable cellular telephone that
it should be thrown in the trash because it isn't fast enough, or isn't
of sufficiently novel technology, and see his or her reaction.



My understanding is that they use SMS for fairly trivial
communications, like what they will have for lunch or where they will
meet at the mall. A rough equivalence might be SMS users objecting to
the use of the SMS system by people who are sitting at full-size
computers or by people who have connected keyboards to their phone. If
they were to complain that "typing" pidgin English (like "HOW R U?")
with your thumbs on a tiny telephone keypad was the one true way to use
SMS, then I think I could agree that there was an equivalence.
You might ask those kids why they also use conventional e-mail,
despite having SMS availability.


To give you an amateur radio example, the Automated Position Reporting
System (APRS):

http://www.aprs.org

uses 1200 Baud AFSK packet. Faster, but still an order of magnitude
slower than technologies you imply should be thrown out.
[...]



Again, it is for the exchange of a single axis of data - geographic
location. Please stop tying to pass off these single purpose, dedicated
systems as examples of general purpose communications.


To even give you a Morse code example, consider the simplicity and
effectiveness of the NCDXF beacons running on the HF bands:

http://www.ncdxf.org/beacons.html



My understanding is that Morse-based beacon identifications are read
by computerized devices and are not "copied" by the pilots. I doubt that
you could find very many current pilots who could copy any Morse at all.


[...]
There are even a number of excellent software packages linked from the
NCDXF site above that could automatically monitor the signals, decode
the Morse, and record the quality of the communications paths over time.
One such package is Faros:

http://www.dxatlas.com/Faros/

one of many advanced signal processing software packages for amateur
radio that exploits the ubiquitousness of of inexpensive personal
computers with sound cards in most home ham "shacks."



There is nothing about that that is unique to Morse. Any type of RF
link would be usable in that way.


Focusing simply on information rate disregards other aspects of the
communications and the channel over which it is transmitted. These
important aspects include the bandwidth and propagation characteristics
of the available channel, the complexity of the required transmitting
and receiving equipment, the amount of data that needs to be
transmitted, and how quickly and often it needs to be conveyed.

Single-attribute measuring contests may be fun, even ego-boosting to
some, but are really not very useful or impressive to those who actually
design and use practical communications systems.

It just seems inconsistent with the way
that so many hams have fought tooth and nail to hold onto Morse and to
hinder the move toward digital modes.


I'm not sure that I understand your line of reasoning here. You are
implying cause-and-effect. In other words, use and advocacy of Morse
code somehow directly contributed to the obstruction of other
technologies. Can you give direct evidence of specific examples?



Hams used to deride digital communications as "pulse" and tell tales
about the way that it squandered bandwidth. They made it out to be
something along the lines of spark-gap. Look for articles about "pulse"
communications in old (1960's and 70's) issues of QST and Popular
Electronics. Considering the lead time needed to develop a new mode, I
think it is unreasonable not to go back at least that far. I believe
that the anti-digital curmudgeons delayed the implementation of digital
modes by a matter of decades. It is interesting to note that the most
widely used digital modes (for 2-way radio, not for broadcast) were
developed either in Japan (Icom/JARL DV) or under the auspices of a
police organization that has no ties to radio, except as consumers (APCO
25).


[...]
Furthermore, if the only technologies that you believe should be saved
from being thrown away are those at 14.4 kBaud and up,



Can you point to something in my post that makes such a claim? The
only technology that I have derided as being too slow as to have value
is Morse code that is sent by hand (less than 100 baud). The Navy shut
down its VLF network on the grounds that the data rate was inadequate.
Perhaps it is time for the amateur community to take a similar step.


those
technologies are only practically realizable on amateur radio bands at
high VHF and up. Such bands have been open to licensees without need of
a Morse code test for going on 17 years now. Even before then, these
bands were accessible to Technician-class amateurs since at least
shortly after World War II, with a license that only required a minimal,
5 WPM (essentially individual character-recognition) Morse code test.

If you are saying that someone *else* should have developed these
technologies (other than you, of course), and that since they haven't,
then someone *must* be to blame, well, you can't really dictate how the
world should turn out without taking an active role to help make it that
way.



That last paragraph is incoherent. Could you rephrase it?

--
Klystron


  #12   Report Post  
Old March 23rd 08, 10:23 PM posted to rec.radio.amateur.moderated
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On Mar 23, 2:33�pm, Klystron wrote:
�Paul W. Schleck " wrote:


For example, the Casio WaveCeptor on my wrist:


http://www.eham.net/reviews/detail/2497
receives a ~ 1 Baud Pulse Position Modulated (PPM)
signal from radio
station WWVB in Fort Collins, Colorado, which transmits
on 60 kHz. �It
takes about a minute to send the complete time code
to synchronize my
watch. �Slow? �Yes. �Useful? �Yes, very

much so,
especially when
considering the coverage and reliability that can be
obtained from such
a low-bandwidth, groundwave-propagated, Very Low
Frequency (VLF) signal.


In your model, only a single axis of data is transmitted - the time
of day. That seems like a great deal of infrastructure and energy
consumption to transmit a single data quantity.


Actually, it's a very small infrastructure, and very efficient. I've
been there, btw.

The time standard info is already present at the WWVB transmitter
site, so that's no cost. All that's necessary is a system to encode
it, and the WWVB transmitter and antenna. While an impressive
installation by amateur radio standards, the WWVB transmitter is
not overly large for the wavelength.

But WWVB's 60 kHz signal serves large numbers of clocks of many types
all over North America - by radio. It keeps them all synchronized via
radio, without any user intervention.

What alternative technology would do the same job with less
infrastructure and energy consumption?

The equivalent
infrastructure for weather transmission (marine and air) is
even more elaborate and expensive.


Of course. But it's also very important from a safety standpoint.

Can you see that is an outrageously inefficient
way to distribute a small quantity of information?


What alternative technology would do the same job with greater
efficiency?

One of the most current and widely used
communications technologies
among young people


Not just "young people". A lot us find text messaging very useful.

is cellular telephone text messaging:


http://en.wikipedia.org/wiki/Text_messaging


(sometimes also called "Short Messaging System" or SMS)


According to this recent demonstration on the
Tonight Show with Jay Leno:


http://www.youtube.com/watch?v=AhsSgcsTMd4


the realizable data rates are comparable in order of magnitude to th

at
of fast Morse code that can be sent and received by human
operators.


The facts are even more telling.

In that Leno clip, the text messager is the Guinness-book
world-record-holder. The Morse Code ops are a couple of
hams who were going less than 30 wpm - which is less than
40% of the world-record Morse Code speed.

The text messager was allowed to use common text-message
abbreviations, while the Morse Code ops just sent the straight
text with no abbreviations at all.

The Morse Code ops also produced a hard-copy in real time.

IMHO, what was most telling was that the audience was sure
the text messager would win. But a much older technology
proved to be faster.

Just try telling a teenager with an SMS-capable cellular
telephone that
it should be thrown in the trash because it isn't fast
enough, or isn't
of sufficiently novel technology, and see his or her reaction.


The answer will be that it's fast enough for what it's used for.

Isn't that the ultimate test of any technology - that it's good
enough for what it's used for?

My understanding is that they use SMS for fairly trivial
communications, like what they will have for lunch or
where they will meet at the mall.


I can say for a fact that's not true. While a lot of text - and cell
phone - communications is trivial, much is not. For example,
something as simple as a meeting place or time can be
critical information.

A rough equivalence might be SMS users objecting to
the use of the SMS system by people who are sitting at full-size
computers or by people who have connected keyboards to their
phone.


Actually the system can be used that way, in that a message generated
by a cell can be delivered as an email, and the
reverse.

The point is that speed isn't the only criterion.

To give you an amateur radio example, the Automated Position Reporti

ng
System (APRS):


http://www.aprs.org


uses 1200 Baud AFSK packet. �Faster, but still an order of magni

tude
slower than technologies you imply should be thrown out.


� �Again, it is for the exchange of a single axis of data

-
geographic
location. Please stop tying to pass off these single purpose,
dedicated
systems as examples of general purpose communications.


No one is trying to do that. The point being made is that speed
is not the only criterion.

What is meant by "general purpose communications"? My computer
allows internet access, email and some other things, but I still have
POTS and a cell phone. TV and radio come to my house over the air.

I'm not sure that I understand your line of reasoning here.
�You are
implying cause-and-effect. �In other words, use and
advocacy of Morse
code somehow directly contributed to the obstruction of other
technologies. �Can you give direct evidence of specific
examples?


Hams used to deride digital communications as "pulse"
and tell tales
about the way that it squandered bandwidth.


I don't know any hams who used the term "pulse" to refer to
digital communications. Nor have I heard tales about squandered
bandwidth.

However, note that not all digital signals are designed with
bandwidth efficiency as the primary consideration. For
example, classic 850 Hz shift 45.45 baud RTTY uses almost
a kHz of band to transmit about the same info (actually
less) as PSK31 which uses maybe 50 Hz.

They made it out to be
something along the lines of spark-gap.


If you mean spark, I have not seen that comparison anywhere.
Could you provide a specific reference?

Look for articles about "pulse"
communications in old (1960's and 70's) issues of QST and
Popular Electronics.


I have all the QSTs back to the mid-1920s, and have read all
of them. I do not recall any comparison of digital modes to
"pulse" in any of them. Could you provide a specific reference?

I do recall some QST articles back in the 1950s *advocating* pulse
modes for use at microwave frequencies. The idea was that
rather than trying to adapt lower frequency narrow band techniques to
the microwave bands, broadband/radar techniques would be used for
communications.

Considering the lead time needed to develop a new mode, I
think it is unreasonable not to go back at least that far.


PSK31 was developed in a few years by G3PLX and a small group of hams
around the world. Lots of other examples.

I believe
that the anti-digital curmudgeons delayed the implementation of
digital
modes by a matter of decades.


How was this done?

The main impediments to the implementation of digital modes by
amateurs (at least in the USA) were two:

1) Restrictive regulations, brought about mostly by the FCC's need
to be able to monitor amateur transmissions. However, note that
digital transmissions other than digital voice are not allowed in the
US HF 'phone subbands - which comprise the majority of the
bandwidth on those bands. Those rules force the digital
data modes to share only with Morse Code users.

2) The high cost of hardware. Only a decade ago, a PC
was a significant investment compared to a ham rig.

It is interesting to note that the most
widely used digital modes (for 2-way radio, not for broadcast)
were
developed either in Japan (Icom/JARL DV) or under the auspices
of a
police organization that has no ties to radio, except as consumers (APCO

25).

They were developed for specific applications, though. Not for general
purpose use.

Furthermore, if the only technologies that you believe
should be saved
from being thrown away are those at 14.4 kBaud and up,


Can you point to something in my post that makes such a claim?


The statement about throwing 14400 modems in the garbage.

The
only technology that I have derided as being too slow as to have
value
is Morse code that is sent by hand (less than 100 baud).


PSK31 and most HF RTTY are also less than 100 baud. Are they
too slow to have value?

The Navy shut
down its VLF network on the grounds that the data rate
was inadequate.


But amateur radio isn't the US Navy. IIRC, the purpose of that
network was/is to communicate one-way to submerged missile
submarines.

Perhaps it is time for the amateur community to take a similar
step.


What form would that step take? Should amateurs simply not
*use* Morse Code any more?

The *test* for the mode was an issue of great contention among
radio amateurs. But until July 2003 the ITU-R treaty prevented
complete elimination of the *test*.

However, as far back as 1990 it was possible to get any US
amateur radio license with just a basic 5 wpm Morse Code
test and a doctor's note. Since April 2000, no doctor's note
has been needed, and since Feb 2007 no Morse Code test
at all.

How any of this has impeded the development or implementation
of digital modes is unclear to me.

those
technologies are only practically realizable on amateur radio
bands at
high VHF and up. �Such bands have been open to licensees
without need of
a Morse code test for going on 17 years now. �Even before
then, these
bands were accessible to Technician-class amateurs since
at least
shortly after World War II, with a license that only required
a minimal,
5 WPM (essentially individual character-recognition)
Morse code test.


The Technician class license was created in 1951. Its Morse Code
test was always 5 wpm, until it was dropped completely in 1991.

IOW, as has been pointed out, practically all of the US amateur bands
above 30 MHz have been available for the development and
implementation of digital modes by amateurs, with no need for any
Morse Code test. Lots of bandwidth, too - all those bands except
222-225 are wider than all the HF/MF amateur bands combined.


73 de Jim, N2EY

  #13   Report Post  
Old March 23rd 08, 11:04 PM posted to rec.radio.amateur.moderated
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First recorded activity by RadioBanter: Aug 2010
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-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

In Klystron writes:

Paul W. Schleck " wrote:
Klystron writes:


It still seems like an awfully slow data rate. I have seen people
throw 14400 Baud modems in the garbage because they considered them to
be so slow as to be worthless. A data rate of 42 bps is about 3 orders
of magnitude slower than that.



Many types of communications vary over many orders of magnitude of
information rate, yet are considered useful and up-to-date.

For example, the Casio WaveCeptor on my wrist:

http://www.eham.net/reviews/detail/2497

receives a ~ 1 Baud Pulse Position Modulated (PPM) signal from radio
station WWVB in Fort Collins, Colorado, which transmits on 60 kHz. It
takes about a minute to send the complete time code to synchronize my
watch. Slow? Yes. Useful? Yes, very much so, especially when
considering the coverage and reliability that can be obtained from such
a low-bandwidth, groundwave-propagated, Very Low Frequency (VLF) signal.
[...]



In your model, only a single axis of data is transmitted - the time
of day. That seems like a great deal of infrastructure and energy
consumption to transmit a single data quantity. The equivalent
infrastructure for weather transmission (marine and air) is even more
elaborate and expensive. Can you see that is an outrageously inefficient
way to distribute a small quantity of information?


Transmitting 50 kilowatts from a single site capable of covering most of
North America, using groundwave propagation, independent of solar
activity, is an "outrageously inefficient way to distribute a small
quantity of information?" Well, I do hope that you are hurrying to
write your Congressman to demand that the National Institute of
Standards and Technology put an immediate end to this grave outrage, and
profound waste of taxpayer's money that has been going on for decades.
After all, what does the NIST know about technology, or useful
communications? Perhaps as little as the engineers and marketers in the
economically successful and useful product field of WWVB watches and
clocks, in your estimation.


One of the most current and widely used communications technologies
among young people is cellular telephone text messaging:

http://en.wikipedia.org/wiki/Text_messaging

(sometimes also called "Short Messaging System" or SMS)

According to this recent demonstration on the Tonight Show with Jay
Leno:

http://www.youtube.com/watch?v=AhsSgcsTMd4

the realizable data rates are comparable in order of magnitude to that
of fast Morse code that can be sent and received by human operators.
Just try telling a teenager with an SMS-capable cellular telephone that
it should be thrown in the trash because it isn't fast enough, or isn't
of sufficiently novel technology, and see his or her reaction.



My understanding is that they use SMS for fairly trivial
communications, like what they will have for lunch or where they will
meet at the mall. A rough equivalence might be SMS users objecting to
the use of the SMS system by people who are sitting at full-size
computers or by people who have connected keyboards to their phone. If
they were to complain that "typing" pidgin English (like "HOW R U?")
with your thumbs on a tiny telephone keypad was the one true way to use
SMS, then I think I could agree that there was an equivalence.
You might ask those kids why they also use conventional e-mail,
despite having SMS availability.


I think you are underestimating the power of SMS. As for the comparison
to E-mail, I don't have to ask, as journalists have already done so,
including this recent article from Slate:

http://www.slate.com/id/2177969/pagenum/all/

Simply put, young people find appeal in the immediacy of small, but
low-latency messages sent in relatively large numbers over a long period
of time, and the information transmitted is far more rich and meaningful
that what you imply above. In many respects, this type of communication
is not stilted or limited, but almost provides the immediacy of a
conversation, without having to run up your voice minute charges or
leave your other callers unable to reach you due to the long-term busy
signal.

Young people do still use E-mail, but in circumstances for which it is
the better choice. They are not seeking some overall best "general
purpose communications" to get their messages across to each other.


To give you an amateur radio example, the Automated Position Reporting
System (APRS):

http://www.aprs.org

uses 1200 Baud AFSK packet. Faster, but still an order of magnitude
slower than technologies you imply should be thrown out.
[...]



Again, it is for the exchange of a single axis of data - geographic
location. Please stop tying to pass off these single purpose, dedicated
systems as examples of general purpose communications.


I didn't realize that only "general purpose communications" were
considered worthwhile. Your previous reply argued that it was
undesirable to use such a low-speed technology as Morse code given that
there were many higher-speed alternatives (faster by "orders of
magnitude" you said). I replied to you that fastest is not always best.
Other issues (previously enumerated by me) might actually dictate the
choice of lower-speed communications as the best choice.

I also don't see "general purpose communications" mentioned in Part 97.
Many "single purpose, dedicated systems" are used by amateurs, and
help fulfill amateur radio's Basis and Purpose. In many cases, a
"single purpose" technology is far more useful than a misfit,
one-size-fits-all, "general purpose" one.

Before we make too many assumptions about an undefined term, perhaps you
can describe what types of "general purpose communications" you would
consider to be worthy goals for the Amateur Radio Service, and which
"single purpose" technologies you would like to see eliminated?

Would you also kindly define what is a "single axis of data," in terms
familiar to those involved in communications engineering and technology?
What, then, would be "multiple axes of data?"

To even give you a Morse code example, consider the simplicity and
effectiveness of the NCDXF beacons running on the HF bands:

http://www.ncdxf.org/beacons.html



My understanding is that Morse-based beacon identifications are read
by computerized devices and are not "copied" by the pilots. I doubt that
you could find very many current pilots who could copy any Morse at all.


So, in other words, you are actually agreeing with my previous reply to
you that there are many useful Morse code based communications
technologies that do not actually require memorized, in-head, copy of
Morse code. I'm glad that we agree on something.

[...]
There are even a number of excellent software packages linked from the
NCDXF site above that could automatically monitor the signals, decode
the Morse, and record the quality of the communications paths over time.
One such package is Faros:

http://www.dxatlas.com/Faros/

one of many advanced signal processing software packages for amateur
radio that exploits the ubiquitousness of of inexpensive personal
computers with sound cards in most home ham "shacks."



There is nothing about that that is unique to Morse. Any type of RF
link would be usable in that way.


Yes. That is somehow a point of disagreement between us? In what way?

I did acknowledge that you could re-engineer the NCDXF beacon system
with one that uses, say, PSK31, but the bandwidth and data rate limits
would still remain. A PC with a soundcard would still be usable for
that system, as you note. I'm sure that the author of Faros could also
quickly adapt, and make a PSK31 version of his NCDXF beacon recording
software package.

Focusing simply on information rate disregards other aspects of the
communications and the channel over which it is transmitted. These
important aspects include the bandwidth and propagation characteristics
of the available channel, the complexity of the required transmitting
and receiving equipment, the amount of data that needs to be
transmitted, and how quickly and often it needs to be conveyed.

Single-attribute measuring contests may be fun, even ego-boosting to
some, but are really not very useful or impressive to those who actually
design and use practical communications systems.

It just seems inconsistent with the way
that so many hams have fought tooth and nail to hold onto Morse and to
hinder the move toward digital modes.


I'm not sure that I understand your line of reasoning here. You are
implying cause-and-effect. In other words, use and advocacy of Morse
code somehow directly contributed to the obstruction of other
technologies. Can you give direct evidence of specific examples?



Hams used to deride digital communications as "pulse" and tell tales
about the way that it squandered bandwidth. They made it out to be
something along the lines of spark-gap. Look for articles about "pulse"
communications in old (1960's and 70's) issues of QST and Popular
Electronics. Considering the lead time needed to develop a new mode, I
think it is unreasonable not to go back at least that far. I believe
that the anti-digital curmudgeons delayed the implementation of digital
modes by a matter of decades. It is interesting to note that the most
widely used digital modes (for 2-way radio, not for broadcast) were
developed either in Japan (Icom/JARL DV) or under the auspices of a
police organization that has no ties to radio, except as consumers (APCO
25).


Wow, these curmudgeons must have been very powerful and effective in
their obstructionism if they undermined entire areas of communications
technology development in this country over the last 30-40 years. I
didn't realize that our national technology infrastructure was so
inflexible and lethargic that it could not recover from these
influences, even after so many decades.

[...]
Furthermore, if the only technologies that you believe should be saved
from being thrown away are those at 14.4 kBaud and up,



Can you point to something in my post that makes such a claim?


Just the introduction to your previous article, where you directly
compare the Baud rate of Morse code with that of "obsolete" telephone
modems. You stated that their data rates differed by "orders of
magnitude," implying that communications technologies that were "orders
of magnitude" slower than telephone modems could be dismissed as
obsolete. Following the natural extension of that argument, then the
only technologies that could be favorably compared to such telephone
modems, and meet your argued standard of non-obsolete, could only be
realized on high VHF and up. As I argued previously, use and advocacy
of Morse code has no bearing on the current deployment of such
technologies, as no Morse code test has been required to access them for
at least 17 years. The Technician-class license has existed for far
longer, and has only a minimal Morse code examination.

The
only technology that I have derided as being too slow as to have value
is Morse code that is sent by hand (less than 100 baud).


So, to summarize:

slow-speed (less than 100 baud) PSK31 : "Good"

similar order-of-magnitude speed Morse code: "Bad"

So, it's not the speed you object to, it's the use of Morse code?
Couldn't you have just stated that, and not gone to the trouble of
bringing in other arguments like speed and bandwidth, or whether a
communications technology is sufficiently "general purpose" or not,
regardless of whether something "general purpose" would be the best
choice in a given circumstance? Just say that you don't like Morse
code. Others would at least give you credit for honesty.

The Navy shut
down its VLF network on the grounds that the data rate was inadequate.
Perhaps it is time for the amateur community to take a similar step.


References please? A Google search returns no evidence that Navy
stations like NAA in Cutler, Maine have gone off-line. Are you possibly
thinking of their ELF experiments that were recently ended? Even if so,
what competing technology is the Navy contemplating that will reliably
contact our submarine fleet that has "gone deep" under many fathoms of
RF-attenuating sea water?

I also didn't realize that amateur radio had similar "networks" that
would need to be shut down.

those
technologies are only practically realizable on amateur radio bands at
high VHF and up. Such bands have been open to licensees without need of
a Morse code test for going on 17 years now. Even before then, these
bands were accessible to Technician-class amateurs since at least
shortly after World War II, with a license that only required a minimal,
5 WPM (essentially individual character-recognition) Morse code test.

If you are saying that someone *else* should have developed these
technologies (other than you, of course), and that since they haven't,
then someone *must* be to blame, well, you can't really dictate how the
world should turn out without taking an active role to help make it that
way.



That last paragraph is incoherent. Could you rephrase it?


Looked pretty coherent to me, but for your benefit, I'll dissect it in
detail:

"If you are saying that someone *else* should have developed these
technologies ..."

In other words, amateur radio has failed to meet some standard of
technology development. Other people were somehow "wasting" their time
doing other things.

"... (other than you, of course) ..."

What have you done to make amateur radio a better place? Have you
written your Congressman? Petitioned the FCC? Worked in the
communications engineering and technology field? Developed amateur radio
software and hardware solutions? You seem to be knowledgeable on many
technical subjects, including the history of that technology over many
decades. Did you try to change things, or are you asserting that you
did not have the skills or abilities to help do so, even working with
others over many decades?

"... and since they haven't, then someone *must* be blamed, ..."

I was implying that you were seeking scapegoats, as it is easier to
blame others than look in the mirror.

"... well, you can't really dictate how the world should turn out
without taking an active role to help make it that way."

In other words, Lead, Follow, or Get Out of the Way. "Sidewalk
Superintendents" have very little influence on society. What is your
choice?

Also, some people seem to confuse actual solutions to problems (whether
in amateur radio, or on the newsgroups) with a contest over who can
become the most "outraged." To quote Jim Kelley, AC6XG:

"Outrage, and a buck-fifty, will get us exactly what?"

--
Klystron


- --
73, Paul W. Schleck, K3FU

http://www.novia.net/~pschleck/
Finger for PGP Public Key

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  #15   Report Post  
Old March 24th 08, 03:53 AM posted to rec.radio.amateur.moderated
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Paul W. Schleck " wrote:

Transmitting 50 kilowatts from a single site capable of covering most of
North America, using groundwave propagation, independent of solar
activity, is an "outrageously inefficient way to distribute a small
quantity of information?" Well, I do hope that you are hurrying to
write your Congressman to demand that the National Institute of
Standards and Technology put an immediate end to this grave outrage, and
profound waste of taxpayer's money that has been going on for decades.
After all, what does the NIST know about technology, or useful
communications? Perhaps as little as the engineers and marketers in the
economically successful and useful product field of WWVB watches and
clocks, in your estimation.



Wouldn't it make more sense to include WWV and WWVH along with WWVB?
Are you familiar with the Internet-based ntp system? Then, there is the
matter of GPS, which has a time capability that is incidental to its
navigation function.


[...]
I think you are underestimating the power of SMS. As for the comparison
to E-mail, I don't have to ask, as journalists have already done so,
including this recent article from Slate:

http://www.slate.com/id/2177969/pagenum/all/

Simply put, young people find appeal in the immediacy of small, but
low-latency messages sent in relatively large numbers over a long period
of time, and the information transmitted is far more rich and meaningful
that what you imply above. In many respects, this type of communication
is not stilted or limited, but almost provides the immediacy of a
conversation, without having to run up your voice minute charges or
leave your other callers unable to reach you due to the long-term busy
signal.

Young people do still use E-mail, but in circumstances for which it is
the better choice. They are not seeking some overall best "general
purpose communications" to get their messages across to each other.



I don't see anything in that that contradicts my statement that SMS
is mainly used for messages of little importance. It is also called CMS,
for casual messaging service.


I didn't realize that only "general purpose communications" were
considered worthwhile.



A multi-purpose system that can match a single-purpose system on the
performance of the objectives of the single-purpose system is generally,
if not universally, considered superior.


Your previous reply argued that it was
undesirable to use such a low-speed technology as Morse code given that
there were many higher-speed alternatives (faster by "orders of
magnitude" you said). I replied to you that fastest is not always best.
Other issues (previously enumerated by me) might actually dictate the
choice of lower-speed communications as the best choice.

I also don't see "general purpose communications" mentioned in Part 97.
Many "single purpose, dedicated systems" are used by amateurs, and
help fulfill amateur radio's Basis and Purpose. In many cases, a
"single purpose" technology is far more useful than a misfit,
one-size-fits-all, "general purpose" one.

Before we make too many assumptions about an undefined term, perhaps you
can describe what types of "general purpose communications" you would
consider to be worthy goals for the Amateur Radio Service, and which
"single purpose" technologies you would like to see eliminated?



Why do you want me to reinvent the wheel? Lets go to the source
(condensed from Part 97.1):

* emergency communications
* contribute to the advancement of the radio art
* advancing skills in both the communication and technical phases of
the art
* expansion of the existing reservoir within the amateur radio service
of trained operators, technicians, and electronics experts
* continuation and extension of the amateurs unique ability to enhance
international goodwill


Would you also kindly define what is a "single axis of data," in terms
familiar to those involved in communications engineering and technology?



A single quantity, like time or location


What, then, would be "multiple axes of data?"



Two or more simultaneous quantities, like time AND location or course
AND speed.


So, in other words, you are actually agreeing with my previous reply to
you that there are many useful Morse code based communications
technologies that do not actually require memorized, in-head, copy of
Morse code. I'm glad that we agree on something.



There is probably no purpose for which Morse can be used as a machine
language where there isn't a choice of other, better suited languages
available. This includes aeronautical beacons. You are grasping at
straws, now.


Wow, these curmudgeons must have been very powerful and effective in
their obstructionism if they undermined entire areas of communications
technology development in this country over the last 30-40 years. I
didn't realize that our national technology infrastructure was so
inflexible and lethargic that it could not recover from these
influences, even after so many decades.



When you look at the development of the Internet, Linux and other
free software, you have to wonder about the infrastructure behind it.
How did it come about? There was no regulatory body. There were no
licenses. There were no "Elmers." Until recently, there wasn't even any
formal schooling available, except on the sort of machinery that existed
only within the Fortune 500. Early Internet users and developers had to
read O'Reilly books and figure it out on their own.
That showed great initiative. It demonstrated the sort of determined,
driven advancement of technology that was once seen in amateur radio.
But that sort of thing has passed ham radio by. It has been a long time
since ham radio was a source of innovation. I blame the Morse cultists
who hijacked amateur radio for use as their personal playground.


Just the introduction to your previous article, where you directly
compare the Baud rate of Morse code with that of "obsolete" telephone
modems. You stated that their data rates differed by "orders of
magnitude," implying that communications technologies that were "orders
of magnitude" slower than telephone modems could be dismissed as
obsolete.



An amusing interpretation. It follows that trains and ships should be
discarded because they are much slower than airplanes.


Following the natural extension of that argument, then the
only technologies that could be favorably compared to such telephone
modems, and meet your argued standard of non-obsolete, could only be
realized on high VHF and up. As I argued previously, use and advocacy
of Morse code has no bearing on the current deployment of such
technologies, as no Morse code test has been required to access them for
at least 17 years. The Technician-class license has existed for far
longer, and has only a minimal Morse code examination.



You left out the faster mode of communication known as "voice." It is
widely used on HF. Further, I once looked at a band plan that showed how
DV could be used on HF. They described a system of HF DV that took up
just slightly more bandwidth than SSB and substantially less than AM.


So, to summarize:

slow-speed (less than 100 baud) PSK31 : "Good"

similar order-of-magnitude speed Morse code: "Bad"

So, it's not the speed you object to, it's the use of Morse code?
Couldn't you have just stated that, and not gone to the trouble of
bringing in other arguments like speed and bandwidth, or whether a
communications technology is sufficiently "general purpose" or not,
regardless of whether something "general purpose" would be the best
choice in a given circumstance? Just say that you don't like Morse
code. Others would at least give you credit for honesty.



Who are these "others" and when did they appoint you as their
spokesman?


References please? A Google search returns no evidence that Navy
stations like NAA in Cutler, Maine have gone off-line. Are you possibly
thinking of their ELF experiments that were recently ended? Even if so,
what competing technology is the Navy contemplating that will reliably
contact our submarine fleet that has "gone deep" under many fathoms of
RF-attenuating sea water?



I am thinking of the site in the Upper Peninsula of Michigan and the
increased reliance on TACAMO aircraft (at the time of the shutdown).


I also didn't realize that amateur radio had similar "networks" that
would need to be shut down.



The infrastructure that is being wasted on Morse includes band
segments that have, until recently, been reserved for its exclusive use.
I am very glad to see that almost all CW segments now allow data modes
(50-50.1 and 144-144.1 being the only exceptions). There is also the
inclusion of keyer provisions in HF radios. It will be interesting to
see what the marketplace does to code tapes and code keys. I don't think
they will last long.
While Morse supporters often point to treaties, the fact is that the
US was one of the last countries to abandon the Morse requirement for an
HF license. Other countries began dropping that requirement many years
earlier, while still claiming to be in compliance with their treaty
obligations. How do you explain that? To me, it sounds like the FCC used
the treaties as a pretext to keep the code requirement in order to
placate the ARRL and the Morse zealots.


Looked pretty coherent to me, but for your benefit, I'll dissect it in
detail:

"If you are saying that someone *else* should have developed these
technologies ..."

In other words, amateur radio has failed to meet some standard of
technology development. Other people were somehow "wasting" their time
doing other things.

"... (other than you, of course) ..."

What have you done to make amateur radio a better place? Have you
written your Congressman? Petitioned the FCC? Worked in the
communications engineering and technology field? Developed amateur radio
software and hardware solutions? You seem to be knowledgeable on many
technical subjects, including the history of that technology over many
decades. Did you try to change things, or are you asserting that you
did not have the skills or abilities to help do so, even working with
others over many decades?



I have worked in the electronics industry. I have made my views clear
to any and all who had an interest in the subject. I made those views as
clear then as I have done in this newsgroup.


"... and since they haven't, then someone *must* be blamed, ..."

I was implying that you were seeking scapegoats, as it is easier to
blame others than look in the mirror.

"... well, you can't really dictate how the world should turn out
without taking an active role to help make it that way."

In other words, Lead, Follow, or Get Out of the Way. "Sidewalk
Superintendents" have very little influence on society. What is your
choice?

Also, some people seem to confuse actual solutions to problems (whether
in amateur radio, or on the newsgroups) with a contest over who can
become the most "outraged." To quote Jim Kelley, AC6XG:

"Outrage, and a buck-fifty, will get us exactly what?"


--
Klystron



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Old March 24th 08, 03:54 AM posted to rec.radio.amateur.moderated
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Paul W. Schleck posted on Sun, 23 Mar 2008 12:03:58 EDT:

Many types of communications vary over many orders of magnitude of
information rate, yet are considered useful and up-to-date.

For example, the Casio WaveCeptor on my wrist:

http://www.eham.net/reviews/detail/2497

receives a ~ 1 Baud Pulse Position Modulated (PPM) signal from radio
station WWVB in Fort Collins, Colorado, which transmits on 60 kHz. It
takes about a minute to send the complete time code to synchronize my
watch. Slow? Yes. Useful? Yes, very much so, especially when
considering the coverage and reliability that can be obtained from such
a low-bandwidth, groundwave-propagated, Very Low Frequency (VLF) signal.
The watch only needs to receive the time code at most once per day,
which it does so automatically in the early hours of the morning sitting
on my desk or dresser. A faster data rate would require something other
than a VLF signal, and would not improve much on the quality or
usability of the communications. It would definitely increase the
price. Witness the much greater success in the marketplace of
WWVB-based watches versus more advanced, higher bandwidth, but much more
expensive, "Smart Personal Object Technology" (SPOT) watches:


Good mention, Paul. Ummm...the data rate is rather exactly one bit per
second and takes exactly 60 seconds to send one frame of time and date
data. :-)

ALL the details are given at www.nist.gov under the 'Time Frequency'
page, including propagation charts at various times of the day and
for various seasons. This southern California region can regularly
receive enough signal to set radio clocks even if at an approximate
distance of about 900 miles to Fort Collins. In 2005 my wife and I
drove to southern Wisconsin and my La Crosse radio wris****ch never
failed to set itself properly even though some of our overnight stays
were in hotels having steel structures or in among other buildings.
We have two radio wall clocks in our residence and those are exact
enough to compare on-the-second with HF time ticks from WWV and WWVH.

[I won't quibble about the PPM mode descriptor since the full details
of modulation are given at NIST website... :-) ]


According to this recent demonstration on the Tonight Show with Jay
Leno:

http://www.youtube.com/watch?v=AhsSgcsTMd4


Ahem...quibble mode on...that little bit on the Tonight Show was
a 'setup' gig that employed two young local male actors as the
(described) "text messaging experts" but the two hams (one of which
would very soon become marketing director for Heil Sound) were
real. That is the input I got directly from a reliable staffer on
the Tonight Show. Took a few phone calls to get that information
but it is an advantage of living inside the entertainment capital of
the USA (aka Los Angeles, CA)...and the NBC western Hq is only
about 5 miles south of my place, down Hollywood Way to Alameda and
then east about a mile. That whole bit was really a send-up on the
popular fad of text messaging done by teeners and young adults.

That bit is about as 'real documentary' as Leno's send-ups on the
'street interviews' with ordinary (apparently clueless) younger
folk on various kinds of knowledge. In short, ONLY for gag purposes.


To even give you a Morse code example, consider the simplicity and
effectiveness of the NCDXF beacons running on the HF bands:

http://www.ncdxf.org/beacons.html


HF beacons are neat for their purposes of checking on HF propagation
paths, but they aren't 'communications' in the regular sense. Those
were also designed for simplicity at the various receiving sites but
require rather precise time-of-day at each receiver in order to get
the start of each cycle.

While I had not intended to restart some morse-vs-others kind of
argument, I have to note where I began HF communications with the
US military some 55 years ago. Not a single communications circuit
used any form of morse coding to achieve a throughput of nearly a
quarter of a million messages per month (average in 1955). The
majority was teleprinter of the 5-level 'Baudot' format running at
60 WPM equivalent rates. 24/7 of course with TTY distributors to
to automatically start another p-tape reader when the other reader
was done. FSK 'spread' was then 850 cycles, not the narrower 170
Hz of today. Radio circuits (where I was assigned) spanned the
northern Pacific from Saigon, Seoul, and Manila to Anchorage,
Seattle, San Francisco, and Hawaii.

In 1955 the Army tried an experiment on a few select radio circuits
to push the Teletype Corporation's machines to 75 WPM equivalent.
End result of that was a failure rate more than double that of the
standard 60 WPM equivalent machines. Teletype seems to have achieved
an optimized design for 60 WPM equivalent; their 100 WPM equivalent
next-generation machines used a different electromechanical system,
were quite reliable at that rate.


very fast determination of the link budget to the beacon locations. If
you can't remember what a "V" sounds like in Morse Code (". . . _" like
the intro to Beethoven's Fifth Symphony), I suppose you could put that
on the chart as well. After all, the use of similar charts are how
pilots usually decode the Morse code identifications of aeronautical
beacons.


Quibble mode on again. The LF aeronautical beacoms are what you are
writing about but they are NOT used much at all for aircraft radio-
navigation now, nor were they a half century ago. Present-day (and in
1962) radionavigation over land is done mainly by VOR (Very high
frequency Omnidirectional Radio range) using a unique 30 Hz antenna
pattern rotation with a reference phase of 30 Hz sent on a 9.96 KHz
subcarrier. Aircraft VOR receivers have used very simple (even for
tube circuits) to determine their bearing to a ground station. These
were simple enough (and low cost enough) for small private general
aviation craft and the US VOR system was adopted internationally in
1955. For distance to a ground station the civil method emplyed a
low L-band interrogator sending a (jittered) double pulse and
measuring the return delay (plus 50 uSec) from the ground station
responder. This DME (Distance Measuring Equipment) was compatible
with military TACAN (TACtical Area Navigation) signal format and the
FAA combined VOR-DME-TACAN equipments on the ground and those are
identified by the contraction VORTAC. On aeronautical charts (from
the government, usually reprinted by private companies) there is
usually a magnetic bearing compass circle (VOR and civil-use-TACAN
reference magnetic reference, not actual north reference)...the
VHF frequencies (DME and TACAN frequencies have been paired with
VOR), ICAO 3-letter ID, and the dot-dash pattern of that 3-letter ID.

The elegant simplicity of VOR is that it will permit AM Voice IN the
ground station transmitter without disturbing the antenna pattern
modulation or the reference phase subcarrier. In congested urban
areas where a lot of general aviation aircraft abound, FAA stations
routinely use VOR voice transmissions to aid civil pilots, easing
the pilots' workload by providing extra information such as WX,
special conditions at an airport. My local airport (BUR) now known
as Bob Hope Airport, the FAA used to send a repeating voice
announcement of local WX conditions, airport info, etc., all
identified by a letter, beginning with A or Alpha at midnight. The
tag on the voice tape loop was "please tell the tower you have
received 'information Foxtrot or whatever letter'" when requesting
landing at that airport. Yes, some VORs transmit the ICAO 3-letter
ID as a low-modulation on-off tone in slow morse but I have yet to
find any civil pilot, beginner to experienced, who USES that code
for radionavigation.

Focusing simply on information rate disregards other aspects of the
communications and the channel over which it is transmitted. These
important aspects include the bandwidth and propagation characteristics
of the available channel, the complexity of the required transmitting
and receiving equipment, the amount of data that needs to be
transmitted, and how quickly and often it needs to be conveyed.


Martinez' PSK31 was rather precisely designed for low (500 Hz)
bandwidth coincident with non-typists typing rate of about 30 WPM
equivalent, all in congested Data slices of amateur radio band
'bandplans' on HF. With relatively simple electronic terminal
equipment with microprocessor-aided operation, I/O memory space
and programming is a minor addition to handle faster typists'
input, even burst typing on a keyboard to 100 WPM or so equivalent.

The OLD FSK bandwidths on HF (of a half century ago) took up about
a whole KHz while using an 850 cycle shift. On the 3 KHz of an old
commercial-format SSB channel (one of four), as many as 8 separate
TTY circuits could be frequency-multiplexed. A more reasonable
shift (to 170 Hz) occurred later with improvements in terminal
equipment technology, is the norm now, even for 100 WPM equivalent
teleprinter rates of those still using electromechanical terminals.

BANDWIDTH occupancy seems to be the primary driver for modulation
rates on HF. YMMV.

There are more complex methods of modulation-demodulation that
have been available for some time. DRM (Digital Radio Mondial) is
one such as has been verified on HF for 'SW BC' (Broadcasting).
That DRM has not spread well among broadcasters has little to do
with technical details of modulation-demodulation, but rather in
the poor propagation conditions of this sunspot cycle limiting
broadcasters' range. If a signal can't get through at all, NO
modulation method is going to help. Besides, with the availability
of satellite radio broadcasting, 'SW BC' has gradually shifted
over to that method rather than using HF directly.


I'm not sure that I understand your line of reasoning here. You are
implying cause-and-effect. In other words, use and advocacy of Morse
code somehow directly contributed to the obstruction of other
technologies. Can you give direct evidence of specific examples? If
you are implying that licensing requirements obstructed the development
of advanced digital modes, that really doesn't appear to be the case.
Witness the success of Tucson Amateur Packet Radio (TAPR):


It is disingenuous to 'force' an argument by introduction of
something not overtly stated by the originator.

TAPR and its membership have done some excellent technical
development and spread of such technology. Note also that its
membership is made up of radio amateurs who've been licensed for
a while and are NOT technical beginners in radio or electronics.

In the view of the ENTIRE world of radio, not just amateur radio, the
use of morse code modes to communicate has steadily decreased for
over a half century. It has decreased so much so that some non-
amateur radio services either stopped using that mode or never
considered it for a new radio service introduced in the last half
century. As a prime example, the changeover to GMDSS and replacement
of the old 500 KHz international distress and safety frequency which
used morse code exclusively. Even the USCG stopped monitoring that
old 500 KHz frequency. GMDSS was designed and approved by the
Maritime Community, not by amateurs.

The decline, or perhaps more accurately, the failure to keep up
with overall population increase (of USA) amateur licensees is (in
my opinion) NOT due exclusively to 'USE' of morse code. US amateur
radio license totals peaked 5 years ago. In general, by informal
polling, newcomers are NOT embracing morse code modes...nor are
they flocking to HF amateur bands. PART of that MAY be due to the
insistence of the 'amateur radio community' to hang onto the morse
code TEST forever. Part of that is due to the slow acceptance of
international amateur radio to change the international amateur
Radio Regulations away from old standards. WRC-03 of nearly 5 years
ago allowed individual administrations to drop the morse code test
for an amateur radio license. The USA did not follow through on
that until more than 3 years later. [precisely, the end of July
2003 to 23 February 2007]

[in response to 'Klystron']

If you are saying that someone *else* should have developed these
technologies (other than you, of course), and that since they haven't,
then someone *must* be to blame, well, you can't really dictate how the
world should turn out without taking an active role to help make it that
way.


That's rather strong wording from a leading person of this
newsgroup, isn't it?

For a very long while, ever since I first began as a pro in HF
radio communications, PART of the 'amateur radio community' had
been very busy 'dictating' how the amateur radio world should be
by the continuation of the morse code test for an amateur radio
license. OTHERS, including those of us (like myself) who were NOT
licensed in amateur radio have actively campaigned to remove that
test from US amateur radio...even though other countries had
already preceded the USA in abolishing that code test. I won't say
that I've 'been responsible' for any USA changes but I was certainly
'active' in trying to do so. The FCC apparently agreed with some
of my views as well as so many others supporting that test
elimination. It came to pass. But, that coming might have been too
late to change others' interests in US amateur radio.

In my electronics work that began (professionally) in 1952, I've
been involved in a lot of different electronics and modes and
modulations of RF that were never allocated for US amateur radio
use. Some of those just wouldn't apply to two-way communications but
others would apply. There are still some US regulations that need
altering but a very vocal PART of the 'amateur radio community'
seems very adamant about NOT upsetting the status quo. The future
of US amateur radio does NOT depend solely on them.

73, Len AF6AY
First licensed in US amateur radio in March 2007
First licensed in US commercial radio in March 1956
First QSY of a 1 KW HF transmitter in February 1953

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Old March 24th 08, 04:29 AM posted to rec.radio.amateur.moderated
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On Sun, 23 Mar 2008 22:53:54 EDT, Klystron wrote:

Wouldn't it make more sense to include WWV and WWVH along with WWVB?
Are you familiar with the Internet-based ntp system? Then, there is the
matter of GPS, which has a time capability that is incidental to its
navigation function.


Want some fun? Compare the time ticks received from WWVB, WWV,
NIST-on-line, and GPS. What, they are not all simultaneous? Welcome
to the real world. GPS time does not correlate with UTC by any means
(several seconds difference).

In one of the first digital military command and control system that I
was involved in during the early 1960s, we used rubidium standards at
our switching centers to get accurate time synchronization, and even
then it was rather crude because the line delays varied so much. HF
propagation (WWV/WWVH) is even worse in that regard.
--

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 24th 08, 05:08 AM posted to rec.radio.amateur.moderated
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On Sun, 23 Mar 2008 22:54:34 EDT, AF6AY wrote:

As a prime example, the changeover to GMDSS and replacement
of the old 500 KHz international distress and safety frequency which
used morse code exclusively. Even the USCG stopped monitoring that
old 500 KHz frequency. GMDSS was designed and approved by the
Maritime Community, not by amateurs.


As those of us who had our ears to the hull, so to speak, know very
well, the main reason was to get rid of "Sparks the Radio Operator"
who was a very large expense for the traffic that was being handled by
non-Morse methods. Some could be retrained as service technicians,
many could not and took retirement.

Be aware, though, that there are still several Public Coast Stations
in the US that are capable and do handle Morse traffic, and twice a
year the USCG fires up its Morse stations. It's not all dead.
--

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 24th 08, 05:09 AM posted to rec.radio.amateur.moderated
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On Mar 23, 8:29�pm, Phil Kane wrote:
On Sun, 23 Mar 2008 22:53:54 EDT, Klystron wrote:
� Wouldn't it make more sense to include WWV and WWVH along with

WWVB?
Are you familiar with the Internet-based ntp system? Then, there is the
matter of GPS, which has a time capability that is incidental to its
navigation function.


Want some fun? �Compare the time ticks received from �WWVB

, WWV,
NIST-on-line, and GPS. �What, they are not all simultaneous?

Welcome
to the real world. �GPS time does not correlate with UTC by any me

ans
(several seconds difference).

In one of the first digital military command and control system that I
was involved in during the early 1960s, we used rubidium standards at
our switching centers to get accurate time synchronization, and even
then it was rather crude because the line delays varied so much. �

HF
propagation (WWV/WWVH) is even worse in that regard.


I've compared each of our three radio-set clocks at this residence (in
Los Angeles) and find excellent correlation between their one-second
changes and both WWV and WWVH. Don't have any GPS receiver
to try the same.

In 1960, while working in the Standards Lab of Ramo-Wooldridge Corp.
in Canoga Park, CA, I got to pull some OT on Saturdays to measure
the difference between east coast transmissions of WWV and the
local General Radio frequency standard. Just a plain old quartz
crystal standard oscillator driving divider chains to the built-in
clock.
I would record the microseconds of difference between local clock
ticks and WWV ticks from the east coast. Not much variation in a
week's time, don't remember just how much (it was 48 years ago).

Yes, propagation on HF does vary but it is sometimes exaggerated.
Before R-W went into a business tailspin, the Standards Lab was
ready to get a low-frequency HP receiver for 20 KHz to improve on
establishing a local, secondary frequency standard. No joy on that
corporation which was eventually sold off. All I ever got to see was
the 'diurnal shift' of 20 KHz phase recordings at sunrise and sunset.
:-)

73, Len AF6AY

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Old March 24th 08, 05:09 AM posted to rec.radio.amateur.moderated
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Jim Haynes posted on Tue, 18 Mar 2008 19:47:44 EDT:

Bill Horne wrote:

I'm sure your explanation is correct, but it leaves me confused: I know
bps baud, but they're close, and the Model 15 Teletype I used to own
operated at 45 baud. It seems illogical that Morse would be so high in
the bps count.


Your Model 15 Teletype at the nominal 60 wpm speed, which is actually
368 chars/minute and 45.45 baud works out like this. The character
length is 7.42 bits long (for ancient, interesting reasons I won't go
into right now) and the bit duration is 22 milliseconds. The character
duration is therefore 7.42 * 22 = 163.24 milliseconds, and that works out
to 6.12595 characters/sec = 367.55 characters/minute. To convert that
to words you have to figure 6 characters per word because the space
between words is also a character. So the speed is actually 61.26
words/minute.


For what it is worth, my paper reference on TTYs is NAVSHIPS
0967-255-0010 "Principles of Telegraphy (Teletypewriter)" from
Department of the Navy Electronic Systems Command. I bought it
from the US Government Printing Office back in the early 1970s as
a reference. [I am an Army veteran, not Navy] The first chapter of
Part A in that TM has a nice historical record of 'telegraphy'
(which includes teletypewriting). It says only "60 WPM" but mentions
other Baud rates.

As far as we in Army communications of the mid-1950s were concerned,
all the teletypewriters that the Army used were called "60 WPM" and
only the teletypewriter maintenance people (and a few carrier systems
types) cared about many numbers. We did have Distortion meters used
to determine irregularities in a circuit.

BTW, the Army and the rest of the military used Teletype Corporation
Model 15s through 19s, variation being only the paper tape punch
and transmitting distributor (P-tape reader).


Now when you get to ASCII, the old Teletype machines transmitted 8
data bits per character and used an 11.0 unit code. This makes 100
wpm work out to 110 baud. Electronic terminals don't need 11 unit
code; they can do just fine with 10. Thus the words-per-minute is
numerically equal to the baud rate. 100 baud - 10 ms/bit -
100 ms/char - 10 chars/sec - 600 chars/min - 100 wpm.


OK on that. Teletype Corporation Model 28s (explained in intimate
detail in the NAVSHIPS TM I referenced) would easily do 100 WPM
equivalent 24/7 as long as supplied with paper, ribbon, and oil. :-)


...word PARIS contains 50 bit times counting the space. So one word
per second is 50 bits per second and 60 wpm. As an aside, the
military sends a lot of encrypted 5-letter code groups, so instead
of PARIS the Signal Corps uses CODEZ as a test word more statistically
correct for their kind of traffic. And CODEZ contains 60 bits.


I never encountered any test word 'CODEZ' 1953 to 1956, nor
elsewhere in the Signal Corps or in DoD contracts after that. In
the mid-50s we simply used a continuous 'R-Y' generator (from
Teletype Corporation) for circuit checks with the old 60 WPM
equivalent machines. Teletype Corp. also made a 'fox test'
generator consisting of a half dozen cams operating as many
switches to generate "The quick brown fox jumped..." sentence
(with Tx station ID at the end) for radio circuit checks.

Electromechanical teletypewriters are now rather passe' in the
military and government (I use a French word to replace Obsolete
which so many have trouble with). It is all electronic and, for
permanent installations, over the DSN (Digital Switched Network)
anywhere...including interfaces with the regular civilian telephone
infrastructure. The DSN allows encryption on-line as per protocol.
For field radios, the electronic data protocols are compatible
with hard-wired ones and also allow encryption on-line. It was so
in the first Gulf War (1990-1991) which 'battle tested' the whole
military communications network DX to no-DX via TDRS (Tracking
and Data Relay Satellites) and other military commsats from/to
Florida to/from the Middle East.

Not having any access to the DSN or intimate details of military
cryptographic equipment now, I have no exact knowledge of what is
used for a test word, sentence, or whatever. For the OLD electro-
mechanical teleprinters, I'd say the specifications for a
specific TTY Distortion Meter would tell the exact story on
timing for both polar and non-polar TTY circuits and equipment.

73, Len AF6AY



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