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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/
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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

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

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? ï
¿½Welcome
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

On Mon, 24 Mar 2008 00:09:24 EDT, AF6AY wrote:

In 1960, while working in the Standards Lab of Ramo-Wooldridge Corp.
in Canoga Park, CA,

Errrr, Len, the Ramo-Wooldridge Corporation went out of existence in
1958 when it merged with Thompson Products to become Thompson Ramo
Wooldridge, Inc. Remember that I started with the "original" R-W in
1957 and was employed by them at the time of the merger at the former
El Segundo Boulevard facilities (I never did get to work at the Arbor
Vitae Street facilities which were the headquarters of the Air Force
Ballistic Missile Division). They didn't move to Canoga Park until
the late fall of 1959, and I was laid off (for the second time) in
June of 1960. Thompson Ramo Wooldridge, Inc - later TRW, Inc. - went
on an acquisitions binge and itself went out of existence in 2002 when
the electronics and aerospace parts were acquired by Grumman (now
Northrop Grumman) and the automotive parts mostly by Goodyear.

In context - RW was always friendly to ham radio, and the pre-merger
RW Corp. actually let us scrounge both new and recycled parts for ham
rigs and audio projects which became our property as long as we signed
a register/release stating what we were building.

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.

While at the El Segundo Blvd. facility we had a project of measuring
distance to a transmitter using the time delay of HF transmissions
received at different sites with a calibrated link between them
(azimuth was easy using standard DF techniques) and we used the GR
frequency standard referenced above. Using WWV was too error-prone.

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).

My references about time differences, BTW, was to the time of day, i.e
the time of the tick, not the interval between the ticks. GPS has a
very noticeable offset compared to NIST.

I guess that it's only nuts like me that care about that. My early
training as a broadcast studio engineer while I was in engineering
school required timing of program starts and endings to the second.
"Dead air" was not permitted. Three o'clock did not mean three
o'clock plus 1 second - the Western Union clock reset pulse on the
hour was broadcast as a "beep".

From my other hobby, "railroad accuracy" of watches (which are
compared with a master clock at the start of a shift) requires one
second per day, 30 seconds per month. Easy to do with quartz watches
nowadays. There even used to be a SP Railroad dial-up number (now
long gone) where the "time man" would announce the time "Southern
Pacific Standard Time is ...." as contrasted to Ma Bell's "time lady"
who would announce "Pacific Standard Time is ..."
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon

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

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 means
(several seconds difference).

Each GPS sattelite has it's own on board atomic clock and the system can
easily provide UTC with accuracy on the few microseconds level with an
ultimate limit of +/- 340 nanoseconds using an appropriate receiver and
hardware.

GPS is the basis for most of the current NTP time servers.

http://www.ntp-time-server.com/gps-t...ime-server.htm


--
Jim Pennino

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On Mon, 24 Mar 2008 00:10:13 EDT, wrote:

Each GPS sattelite has it's own on board atomic clock and the system can
easily provide UTC with accuracy on the few microseconds level with an
ultimate limit of +/- 340 nanoseconds using an appropriate receiver and
hardware.

Something must have changed (or been fixed) then - we made
measurements about three years ago and there was about six seconds
offset - an eternity for accurate time measurements. 340 nanoseconds
we can tolerate. Six seconds we can't.
--

73 de K2ASP - Phil Kane

From a Clearing in the Silicon Forest
Beaverton (Washington County) Oregon

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

Phil Kane wrote:

Something must have changed (or been fixed) then - we made
measurements about three years ago and there was about six seconds
offset - an eternity for accurate time measurements. 340 nanoseconds
we can tolerate. Six seconds we can't.



Could "selective availability" have anything to do with that?

--
Klystron

In article ,
Klystron wrote:
Phil Kane wrote:

Something must have changed (or been fixed) then - we made
measurements about three years ago and there was about six seconds
offset - an eternity for accurate time measurements. 340 nanoseconds
we can tolerate. Six seconds we can't.



Could "selective availability" have anything to do with that?

No.

Klystron wrote:
Phil Kane wrote:

Something must have changed (or been fixed) then - we made
measurements about three years ago and there was about six seconds
offset - an eternity for accurate time measurements. 340 nanoseconds
we can tolerate. Six seconds we can't.

Could "selective availability" have anything to do with that?

It was turned off about 7 years ago and even then just put the ultimate
accuracy in the low microsecond range.

GPS has never been off by six seconds.

--
Jim Pennino

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