HI
A died in the wool Time Nut who doesn't care what time it is - what's the
world coming to
Bob
Hi Bob,
I think you mean dyed in the wool. A *died* in the wool time nut could be
used to describe a frozen 19th century sextant and sidereal pendulum clock
carrying Antarctic
More importantly, how many things don't really need a clock to begin
with! :)
Every piece of equipment in our house shows a different time. I
wouldn't complain if they all automatically adjusted. My current
solution is to just stop looking at the clocks, and it's amazing how
much easier life
More importantly, how many things don't really need a clock to begin
with! :)
ABSOLUTELY!
If you turn on the coffee maker when you walk int the kitchen, it'll be
done by the time you fix breakfast. And so on...
A clock on almost everything is totally superfluous, IMO. Things that do
need to
Confucius say: Man with two clocks never know what time it is.
Al
Every piece of equipment in our house shows a different time. I
wouldn't complain if they all automatically adjusted. My current
solution is to just stop looking at the clocks, and it's amazing how
much easier life gets if
HI
A died in the wool Time Nut who doesn't care what time it is - what's the world
coming to
Bob
On Jul 16, 2012, at 9:34 AM, J. Forster wrote:
More importantly, how many things don't really need a clock to begin
with! :)
ABSOLUTELY!
If you turn on the coffee maker when you walk
Just because I like Brie, doesn't mean I like French Bread or wine.
I am interested in Standards of Time Interval for engineering purposes.
I havn't looked at my oven clock in probably 25 years. I presume it's
accurate twice a day or somewhere on earth, but I couldn't care less.
IMO, adding a
PS:
30 odd years ago, I bought a toaster for about $20 that worked fine and
made good toast until recently. It only failed because a piece of bread
got jammed and was impossible to clean.
So, I bought a new toaster, for about the same price. It didn't last 30
weeks.
In my view, this is NOT
I just hope it didn't died on the last leapsecond...?
On 16/07/2012 22:50, J. Forster wrote:
PS:
30 odd years ago, I bought a toaster for about $20 that worked fine and
made good toast until recently. It only failed because a piece of bread
got jammed and was impossible to clean.
So, I bought
On 07/14/2012 06:47 AM, Brooke Clarke wrote:
Hi:
The key thing GPS is lacking is Daylight Savings Time.
WWV WWVB have the DST bits that allow a clock to show the local time.
One reason GPS doesn't have it is that it is not coordinated globally.
For instance, US is not shifting DST at the
Hi
I think the answer to how many places would it be used is to simply count the
number of things that have the wrong time on them each time the power burps.
There are maybe a dozen gizmos like that in this room (yes I'm in the kitchen).
Bob
On Jul 14, 2012, at 12:41 AM, Hal Murray wrote:
I don't see why school crossing signs, water sprinklers, street or outdoor
lighting need 1 second timing. Ten minutes, or a photocell, would be more
than adequate.
Synchronized traffic lights, perhaps. But there are other cheaper, ways of
doing that like a simple radio link.
-John
On Sat, Jul 14, 2012 at 06:15:14AM -0700, J. Forster wrote:
I don't see why school crossing signs, water sprinklers, street or outdoor
lighting need 1 second timing. Ten minutes, or a photocell, would be more
than adequate.
While there are many many other applications, the issue for
On Wed, Jul 11, 2012 at 03:48:52PM -0400, paul swed wrote:
David
Read your comments and have been traveling. So finally a chance to email.
I read the document also and walked away with what I shared.
In your reading would you believe the following.
Its an absolute phase and that when it
On 07/14/2012 01:49 AM, David I. Emery wrote:
On Wed, Jul 11, 2012 at 03:48:52PM -0400, paul swed wrote:
David
Read your comments and have been traveling. So finally a chance to email.
I read the document also and walked away with what I shared.
In your reading would you believe the
On Sat, Jul 14, 2012 at 02:38:34AM +0200, Magnus Danielson wrote:
I think the PTTI article isn't as much documentation as presentation of
general principle, showing details more as to present how it can be
done, but not necessarily guarantee it will be done that way. Knowing
the
d...@dieconsulting.com said:
There are innumerable applications for low cost low power human level 1
second accurate time of day in modern electronic systems - examples are
traffic lights and school crossing signs and water sprinklers and street
lights and other outdoor lighting and many
Hi:
The key thing GPS is lacking is Daylight Savings Time.
WWV WWVB have the DST bits that allow a clock to show the local time.
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
___
time-nuts
On Fri, Jul 13, 2012 at 09:47:12PM -0700, Brooke Clarke wrote:
Hi:
The key thing GPS is lacking is Daylight Savings Time.
WWV WWVB have the DST bits that allow a clock to show the local time.
And that is important for most routine civil human use.
Nor something that could
[mailto:time-nuts-boun...@febo.com] On
Behalf Of David I. Emery
Sent: Friday, July 13, 2012 8:35 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Phase modulation detection/NIST plan
On Sat, Jul 14, 2012 at 02:38:34AM +0200, Magnus Danielson wrote:
I think
David
Read your comments and have been traveling. So finally a chance to email.
I read the document also and walked away with what I shared.
In your reading would you believe the following.
Its an absolute phase and that when it switches to 0 there is 1
transition at the beginning of the second
David
Read your comments and have been traveling. So finally a chance to email.
I read the document also and walked away with what I shared.
In your reading would you believe the following.
Its an absolute phase and that when it switches to 0 there is 1 transition
at the beginning of the second
There is an advantage to BPSK switching at the zero crossings in that the
spectrum is significantly narrowed.
-John
==
Could not the phase modulation be made +/-90 degrees, with the appropriate
number of stuff bits being added so that the average phase remains
constant?
Would
HI
My assumption is that for what we would be doing, one lock is all it's going to
take. The local clock will be good enough to allow you to never need to
re-aquire. You will indeed steer to maintain phase, but you already have and
know what's coming in on the modulation.
Bob
On Jul 8,
On 07/09/2012 03:32 AM, Bob Camp wrote:
HI
My assumption is that for what we would be doing, one lock is all it's going to
take. The local clock will be good enough to allow you to never need to
re-aquire. You will indeed steer to maintain phase, but you already have and
know what's coming
Hi
Leap seconds may never happen if PHK gets things organized … :)…
Cycle slips are the main thing you would be watching for. The slow steer to
maintain synch is to catch or correct cycle slips.
Bob
On Jul 9, 2012, at 6:15 PM, Magnus Danielson wrote:
On 07/09/2012 03:32 AM, Bob Camp wrote:
Ei
Sorry if I have your name reversed. By taking this approach it
eliminates the ability to use wwvb as a frequency reference because it
destroys that traceability.
Thats what we are trying to preserve. Or at least re-establish for the
older phase measuring receivers.
Regards
Paul
On
Any possibility of using the decoded signal to un-do the modulation and
feed the reconstituted signal to the older receiver?
On 7/8/2012 12:56 PM, paul wrote:
Ei
Sorry if I have your name reversed. By taking this approach it
eliminates the ability to use wwvb as a frequency reference
Peter indeed there could be
But it should not need to be decoded to undo the psk.
Plus documentation lacks some of the details I think to actually do it.
But that would be a significant project since the formats not been
settled completely yet.
Regards
Paul.
On 7/8/2012 6:40 PM, Peter
Hi Peter,
That's be the hard way, but yes, if the message BPSK coded is computable
and of a known format. If the message contained more than time, like solar
flux, it gets more complicated very rapidly.
A similar thing was done with the Equatorial system 30+ years ago. In that
case, each data
Hi
In this case the data format and it's contents are highly computable. If you
have a good local clock *and* an initial lock, the rest of what follows is
predictable. That of course assumes we know the real format ….
Bob
On Jul 8, 2012, at 6:58 PM, J. Forster wrote:
Hi Peter,
That's be
A risky assumption, and a cold start could be tricky.
Equatorial took many minutes to lock up, with a much higher data rate, and
it did it by slowly sweeping the local clock.
Aside: That's why military spread spectrum systems like good local clocks.
They lock up a whole lot faster that way.
On 07/09/2012 12:46 AM, paul wrote:
Peter indeed there could be
But it should not need to be decoded to undo the psk.
Plus documentation lacks some of the details I think to actually do it.
But that would be a significant project since the formats not been
settled completely yet.
I have
Ei
Sorry if I have your name reversed. By taking this approach it
eliminates the ability to use wwvb as a frequency reference because it
destroys that traceability.
Thats what we are trying to preserve. Or at least re-establish for the
older phase measuring receivers.
Regards
Paul
Are you getting
Hi
The clocks we would be using are *much* better than what most military systems
use….
I also *assume* that an initial lock up that takes a hour is perfectly
acceptable in this application. You will still need a lot of hours / days /
what ever of data to get useful stability off of WWVB,
Hi
The gotcha is that they may change the sync word based on test data. They may
also tweak other vague points in the spec based on the troubles they run into
in their tests or with their silicon.
Bob
On Jul 8, 2012, at 8:07 PM, Magnus Danielson wrote:
On 07/09/2012 12:46 AM, paul wrote:
If you have a deep fade every few hours or minutes, as is common, relock
time becomes an issue.
-John
==
Hi
The clocks we would be using are *much* better than what most military
systems use
.
I also *assume* that an initial lock up that takes a hour is perfectly
acceptable
There is not an infinity of good sync words. A typical good sync word has
a high positive autocorrelation when synced, sloping downwards
monotonically.
Thus the cross-correlation of the received word with a locally stored
reference can be used to steer the loop using a small dither and a lock-in
Could not the phase modulation be made +/-90 degrees, with the appropriate
number of stuff bits being added so that the average phase remains constant?
Would the older receivers simply average out the phase variation over a
longer period?
David GM8ARV
--
SatSignal Software - Quality software
On Sun, Jul 08, 2012 at 09:02:53PM -0400, Bob Camp wrote:
Hi
The gotcha is that they may change the sync word based on test data.
They may also tweak other vague points in the spec based on the troubles
they run into in their tests or with their silicon.
I finally read the
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