Re: Time question on GPS TIME and leap second.

2017-02-02 Thread Larry McDavid 
While I am truly fond of analog clocks, certainly including sundials, I 
also have a place in my heart for interesting digital clocks. Hence, I 
still have two Heathkit "Most Accurate Clocks," model GC-1000, that run 
24/7 and have done for 30 years. This red LED digital clock sets its 
time from WWV (not WWVB) using the two-tone, seconds-tick tone; that 
seconds-tick tone digitally encodes the time of day, DST and more. The 
Heath clock decodes it, displaying hours, minutes, seconds and tenths of 
seconds. For its era, this Heath clock has many innovative features, 
including learning and correcting the frequency error of its internal 
crystal. Originally a relatively expensive Heathkit product selling for 
about $250, it now sells for $400-$600 on eBay!


Bet you did not know the WWV seconds-tick tone actually shifts between 
two different tones to allow this encoding! No, I can't hear the difference.


But, that was before GPS time. I recently found a kit for a red LED 
digital clock that uses GPS and displays hours, minutes, seconds and 
also tenths of seconds. Try that with a sundial! Of course, you don't 
need to plug in your sundial...


Look here for the $60 GPS Clock:

https://www.tindie.com/products/nsayer/gps-clock/

I've had one of these GPS Clocks running for about a month and it has 
been absolutely reliable, syncing quickly to GPS upon power-up from a 5 
volt wall wart power supply.


Larry


On 1/31/2017 11:46 PM, rodwall1...@gmail.com wrote:

A recent article on the GPS analog clock driver. A better description;

http://archive.siliconchip.com.au/cms/A_92/article.html

Roderick Wall.

...

--
Best wishes,

Larry McDavid W6FUB
Anaheim, California  (SE of Los Angeles, near Disneyland)
---
https://lists.uni-koeln.de/mailman/listinfo/sundial

Re: Time question on GPS TIME and leap second.

2017-02-02 Thread rodwall1...@gmail.com 
atory  
> > Web:http://gge.unb.ca<http://gge.unb.ca/>  |
> > | Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   
> > |
> > | University of New Brunswick   Fax:  +1 506 453-4943   
> > |
> > | Fredericton, N.B., Canada  E3B 5A3            
> > |
> > |Fredericton?  Where's that?  
> > See:http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
> >|
> > -
> > 
> > From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
> > <bro...@pacific.net>
> > Sent: Monday, January 30, 2017 4:29 PM
> > To: sundial list
> > Subject: Re: Time question on GPS TIME and leap second.
> >
> > Hi Roderick:
> >
> > GPS time is continuous, that's to say there are no leap seconds or other 
> > changes to it since it started.  It uses a 10 bit binary week counter so 
> > the week number rolls over after 1024 weeks.  This causes problems for GPS 
> > receivers that are more than a few years old since they have no idea what 
> > year it is.
> > The total number of seconds offset from UTC is transmitted separately so 
> > that a GPS receiver can display either GPS time or UTC.
> > Note that the time and position are independent from the year.
> >
> >http://www.prc68.com/I/Trimpack.shtml#WkRlvr
> >
> > --
> > Have Fun,
> >
> > Brooke Clarke
> >http://www.PRC68.com
> >http://www.end2partygovernment.com/2012Issues.html
> >
> >
> >  Original Message 
> > Hi all,
> >
> > Was just listening to the CrowdScience on time. Thanks to whoever posted 
> > the link to it.
> >
> > CrowdScience indicated that a leap second was not added for the GPS. They 
> > also indicated that the GPS gives us UTC time.
> >
> > Question:
> > The UTC time that the GPS gives. Does that have the leap second added?
> >
> > Thanks,
> >
> > Regards,
> >
> > Roderick Wall.
> >
> > - Reply message -
> > From: "Michael Ossipoff" 
> > <email9648...@gmail.com><mailto:email9648...@gmail.com>
> > To: "Robert Kellogg" <rkell...@comcast.net><mailto:rkell...@comcast.net>
> > Cc: "sundial list" <sundial@uni-koeln.de><mailto:sundial@uni-koeln.de>
> > Subject: Why we should reform the Calendar
> > Date: Mon, Jan 30, 2017 8:00 AM
> >
> >
> > On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
> > <rkell...@comcast.net><mailto:rkell...@comcast.net>
> > wrote:
> >
> > > Michael goes off looking for the ideal tropical year
> >
> >
> > There isn't an "ideal tropical year", but, as a choice for a
> > leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
> > best for year-round reduction of longterm calendar-drift.  ...and the
> > average of the lengths of the March & September Equinox tropical years
> > (I'll call that the Average Equinox Year (AEY) ) is a compromise between
> > the vernal equinoxes of the North & the South.
> >
> >
> > > , perhaps ignoring effects of the earth's nutations.
> > >
> >
> > Of course. The nutations are small in amplitude & period. They aren't part
> > of calendar rules. The mean equinox (nutations averaged-out) is the one
> > that is meant when the equinox is spoken of with regard to calendars.
> >
> >
> >
> > > I'll still take the one of 1900, most importantly because it defines the
> > > SI second.
> >
> >
> > The SI second was defined as 1/86,400 of a mean solar day, for some year in
> > the early 19th century. I don't remember exactly what year that was. 1820?
> > 1840? 1850?
> >
> > Evidently it isn't practical to update the length of the SI second, but
> > that doesn't mean that calendars have to be based on the ephemeris day, or
> > atomic day, consisting of 86,400 SI seconds, when that's known to be
> > different from today's mean solar day.
> >
> > That's why I suggest 365.24217 instead of 365.24219 for the length of the
> > mean tropical year (MTYI. It makes sense to base a calendar leap-year
> > rule's mean-year on the actual length of a tropical-year (whichever one we
> > want to use) on the length of that

Re: Time question on GPS TIME and leap second.

2017-02-02 Thread Brooke Clarke 

Hi Rod:

OK, that allows you to set the clock., but it's not a stand alone self setting 
clock.
I was disappointed with the Heathkit GC-1000 when I found that it was off by an hour at the changes of daylight savings 
in displaying my local time.  (It changed time when the transmitter in Colorado changed it's time rather than when it 
should.)  As far as I know that was never fixed.


GPS does not know about the date or daylight savings, but does have a way to get to UTC by using the accumulated offset 
between GPS and UTC.


So the only way to have an accurate and self setting clock is to make use of a "time" station like WWV or WWVB.  I've 
only heard of one clock model that makes use of the phase modulation that's been on WWVB for many years and it's the La 
Crosse 404-1235UA-SS.


--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 

Hi Brooke,

True, GPS doesn't know about daylight saving.

To set the clock up after building it. You use a RS232 Com terminal program, to talk to the clock driver 
microprocessor. And set up the month and which Sunday daylight saving starts and finishes.


You need to:
Set your time zone.
Daylight saving ON or OFF.
Start daylight saving month.
Start daylight saving Sunday.
End daylight saving month.
End daylight saving Sunday.
Set clock pulse mSeconds.
Set GPS update (hours).

Q = quit.

Command:_

The firmware is written in the C language. Source code can be downloaded and 
you can play around with it if you want.

Article also gives a web link for the free Hi-Tech C Compiler.

I'm waiting to see if a local electronic supplier produces a kit of parts for 
it.

Looks like fun,

Roderick Wall.

- Reply message -
From: "Brooke Clarke" <bro...@pacific.net>
To: "sundial list" <sundial@uni-koeln.de>
Subject: Time question on GPS TIME and leap second.
Date: Thu, Feb 2, 2017 9:26 AM

Hi Roderick:

GPS knows about neither daylight savings nor the date.
The article mentions "understands the rules of daylight saving (DST)" which are 
a political thing so this will only work
until the rules change.
This happened to VCR players and after the rules change they are always wrong.
The only time source that knows about these things are the time stations, like WWV 
& WWVB.
http://www.prc68.com/I/timefreq.shtml#RSL

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 
> A recent article on the GPS analog clock driver. A better description;
>
>http://archive.siliconchip.com.au/cms/A_92/article.html
>
> Roderick Wall.
>
> - Reply message -
> From: "Richard Langley" <l...@unb.ca>
> To: "Brooke Clarke" <bro...@pacific.net>, "sundial list" 
<sundial@uni-koeln.de>
> Subject: Time question on GPS TIME and leap second.
> Date: Tue, Jan 31, 2017 10:33 AM
>
> "This causes problems for GPS receivers that are more than a few years old since 
they have no idea what year it is."
>
>
> Not quite true. One of the continuously operating receivers at UNB is more 
than 15 years old. Please see:
>
>http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf​ 
<http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf%E2%80%8B>  
> <http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf%E2%80%8B>

>
>
> -- Richard Langley
>
>
> -
> | Richard B. LangleyE-mail: l...@unb.ca |
> | Geodetic Research Laboratory  
Web:http://gge.unb.ca<http://gge.unb.ca/>  |
> | Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
> | University of New Brunswick   Fax:  +1 506 453-4943   |
> | Fredericton, N.B., Canada  E3B 5A3|
> |Fredericton?  Where's that?  
See:http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
   |
> -------------
> ____
> From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
<bro...@pacific.net>
> Sent: Monday, January 30, 2017 4:29 PM
> To: sundial list
> Subject: Re: Time question on GPS TIME and leap second.
>
> Hi Roderick:
>
> GPS time is continuous, that's to say there are no leap seconds or other 
changes to it since it started.  It uses a 10 bit binary week counter so the week 
number rolls over after 1024 weeks.  This causes problems for GPS receivers that 
are more than a few years old since

Re: Time question on GPS TIME and leap second.

2017-02-01 Thread rodwall1...@gmail.com 
Hi Brooke,
True, GPS doesn't know about daylight saving.

To set the clock up after building it. You use a RS232 Com terminal program, to 
talk to the clock driver microprocessor. And set up the month and which Sunday 
daylight saving starts and finishes.

You need to:
Set your time zone.
Daylight saving ON or OFF.
Start daylight saving month.
Start daylight saving Sunday.
End daylight saving month.
End daylight saving Sunday.
Set clock pulse mSeconds.
Set GPS update (hours).

Q = quit.

Command:_

The firmware is written in the C language. Source code can be downloaded and 
you can play around with it if you want.

Article also gives a web link for the free Hi-Tech C Compiler.

I'm waiting to see if a local electronic supplier produces a kit of parts for 
it.

Looks like fun,

Roderick Wall.

- Reply message -
From: "Brooke Clarke" <bro...@pacific.net>
To: "sundial list" <sundial@uni-koeln.de>
Subject: Time question on GPS TIME and leap second.
Date: Thu, Feb 2, 2017 9:26 AM

Hi Roderick:

GPS knows about neither daylight savings nor the date.
The article mentions "understands the rules of daylight saving (DST)" which are 
a political thing so this will only work 
until the rules change.
This happened to VCR players and after the rules change they are always wrong.
The only time source that knows about these things are the time stations, like 
WWV & WWVB.
http://www.prc68.com/I/timefreq.shtml#RSL

-- 
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 
> A recent article on the GPS analog clock driver. A better description;
>
> http://archive.siliconchip.com.au/cms/A_92/article.html
>
> Roderick Wall.
>
> - Reply message -
> From: "Richard Langley" <l...@unb.ca>
> To: "Brooke Clarke" <bro...@pacific.net>, "sundial list" 
> <sundial@uni-koeln.de>
> Subject: Time question on GPS TIME and leap second.
> Date: Tue, Jan 31, 2017 10:33 AM
>
> "This causes problems for GPS receivers that are more than a few years old 
> since they have no idea what year it is."
>
>
> Not quite true. One of the continuously operating receivers at UNB is more 
> than 15 years old. Please see:
>
> http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf​ 
> <http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf%E2%80%8B>
>
>
> -- Richard Langley
>
>
> -
> | Richard B. LangleyE-mail: l...@unb.ca |
> | Geodetic Research Laboratory  
> Web:http://gge.unb.ca<http://gge.unb.ca/>  |
> | Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
> | University of New Brunswick   Fax:  +1 506 453-4943   |
> | Fredericton, N.B., Canada  E3B 5A3|
> |Fredericton?  Where's that?  
> See:http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
>|
> -------------
> ____
> From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
> <bro...@pacific.net>
> Sent: Monday, January 30, 2017 4:29 PM
> To: sundial list
> Subject: Re: Time question on GPS TIME and leap second.
>
> Hi Roderick:
>
> GPS time is continuous, that's to say there are no leap seconds or other 
> changes to it since it started.  It uses a 10 bit binary week counter so the 
> week number rolls over after 1024 weeks.  This causes problems for GPS 
> receivers that are more than a few years old since they have no idea what 
> year it is.
> The total number of seconds offset from UTC is transmitted separately so that 
> a GPS receiver can display either GPS time or UTC.
> Note that the time and position are independent from the year.
>
> http://www.prc68.com/I/Trimpack.shtml#WkRlvr
>
> --
> Have Fun,
>
> Brooke Clarke
> http://www.PRC68.com
> http://www.end2partygovernment.com/2012Issues.html
>
>
>  Original Message 
> Hi all,
>
> Was just listening to the CrowdScience on time. Thanks to whoever posted the 
> link to it.
>
> CrowdScience indicated that a leap second was not added for the GPS. They 
> also indicated that the GPS gives us UTC time.
>
> Question:
> The UTC time that the GPS gives. Does that have the leap second added?
>
> Thanks,
>
> Regards,
>
> Roderick Wall.
>
> - Reply message -
> From: "Michael Ossipo

Re: Time question on GPS TIME and leap second.

2017-02-01 Thread Brooke Clarke 

Hi Roderick:

GPS knows about neither daylight savings nor the date.
The article mentions "understands the rules of daylight saving (DST)" which are a political thing so this will only work 
until the rules change.

This happened to VCR players and after the rules change they are always wrong.
The only time source that knows about these things are the time stations, like WWV 
& WWVB.
http://www.prc68.com/I/timefreq.shtml#RSL

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 

A recent article on the GPS analog clock driver. A better description;

http://archive.siliconchip.com.au/cms/A_92/article.html

Roderick Wall.

- Reply message -
From: "Richard Langley" <l...@unb.ca>
To: "Brooke Clarke" <bro...@pacific.net>, "sundial list" <sundial@uni-koeln.de>
Subject: Time question on GPS TIME and leap second.
Date: Tue, Jan 31, 2017 10:33 AM

"This causes problems for GPS receivers that are more than a few years old since 
they have no idea what year it is."


Not quite true. One of the continuously operating receivers at UNB is more than 
15 years old. Please see:

http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf​ 
<http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf%E2%80%8B>



-- Richard Langley


-
| Richard B. LangleyE-mail: l...@unb.ca |
| Geodetic Research Laboratory  
Web:http://gge.unb.ca<http://gge.unb.ca/>  |
| Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
| University of New Brunswick   Fax:  +1 506 453-4943   |
| Fredericton, N.B., Canada  E3B 5A3|
|Fredericton?  Where's that?  
See:http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
   |
-

From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
<bro...@pacific.net>
Sent: Monday, January 30, 2017 4:29 PM
To: sundial list
Subject: Re: Time question on GPS TIME and leap second.

Hi Roderick:

GPS time is continuous, that's to say there are no leap seconds or other 
changes to it since it started.  It uses a 10 bit binary week counter so the 
week number rolls over after 1024 weeks.  This causes problems for GPS 
receivers that are more than a few years old since they have no idea what year 
it is.
The total number of seconds offset from UTC is transmitted separately so that a 
GPS receiver can display either GPS time or UTC.
Note that the time and position are independent from the year.

http://www.prc68.com/I/Trimpack.shtml#WkRlvr

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html


 Original Message 
Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" <email9648...@gmail.com><mailto:email9648...@gmail.com>
To: "Robert Kellogg" <rkell...@comcast.net><mailto:rkell...@comcast.net>
Cc: "sundial list" <sundial@uni-koeln.de><mailto:sundial@uni-koeln.de>
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM


On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
<rkell...@comcast.net><mailto:rkell...@comcast.net>
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I do

Re: Time question on GPS TIME and leap second.

2017-01-31 Thread rodwall1...@gmail.com 
A recent article on the GPS analog clock driver. A better description;
http://archive.siliconchip.com.au/cms/A_92/article.html

Roderick Wall.

- Reply message -
From: "Richard Langley" <l...@unb.ca>
To: "Brooke Clarke" <bro...@pacific.net>, "sundial list" <sundial@uni-koeln.de>
Subject: Time question on GPS TIME and leap second.
Date: Tue, Jan 31, 2017 10:33 AM

"This causes problems for GPS receivers that are more than a few years old 
since they have no idea what year it is."


Not quite true. One of the continuously operating receivers at UNB is more than 
15 years old. Please see:

http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf​


-- Richard Langley


-
| Richard B. LangleyE-mail: l...@unb.ca |
| Geodetic Research Laboratory  Web: 
http://gge.unb.ca<http://gge.unb.ca/>  |
| Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
| University of New Brunswick   Fax:  +1 506 453-4943   |
| Fredericton, N.B., Canada  E3B 5A3|
|Fredericton?  Where's that?  See: 
http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
   |
-

From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
<bro...@pacific.net>
Sent: Monday, January 30, 2017 4:29 PM
To: sundial list
Subject: Re: Time question on GPS TIME and leap second.

Hi Roderick:

GPS time is continuous, that's to say there are no leap seconds or other 
changes to it since it started.  It uses a 10 bit binary week counter so the 
week number rolls over after 1024 weeks.  This causes problems for GPS 
receivers that are more than a few years old since they have no idea what year 
it is.
The total number of seconds offset from UTC is transmitted separately so that a 
GPS receiver can display either GPS time or UTC.
Note that the time and position are independent from the year.

http://www.prc68.com/I/Trimpack.shtml#WkRlvr

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html


 Original Message 
Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" <email9648...@gmail.com><mailto:email9648...@gmail.com>
To: "Robert Kellogg" <rkell...@comcast.net><mailto:rkell...@comcast.net>
Cc: "sundial list" <sundial@uni-koeln.de><mailto:sundial@uni-koeln.de>
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM


On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
<rkell...@comcast.net><mailto:rkell...@comcast.net>
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I don't remember exactly what year that was. 1820?
1840? 1850?

Evidently it isn't practical to update the length of the SI second, but
that doesn't mean that calendars have to be based on the ephemeris day, or
atomic day, consisting of 86,400 SI seconds, when that's known to be
different from today's mean solar day.

That's why I suggest 365.24217 instead of 365.24219 for the length of the
mean tropical year (MTYI. It makes sense to base a calendar leap-year
rule's mean-year on the actual length of a tropical-year (whichever one we
want to use) on the length of that tropical year in* today's* mean days.


>
>
> So, contemplating changing the year is n

Re: Time question on GPS TIME and leap second.

2017-01-31 Thread rodwall1...@gmail.com 
Thanks to all who replied to my questions about the time on GPS.
The reason I asked about the leap second. Is if the following analog clock GPS 
driver included the leap second correction.

Yes it would.

http://www.altronics.com.au/p/k1129-gps-synchronised-clock-kit/

It also corrects it for daylight saving.

Thanks all,

Roderick Wall.

- Reply message -
From: "Brooke Clarke" 
To: "sundial list" 
Subject: Time question on GPS TIME and leap second.
Date: Tue, Jan 31, 2017 7:29 AM

Hi Roderick:

GPS time is continuous, that's to say there are no leap seconds or other 
changes to it since it started.  It uses a 10 
bit binary week counter so the week number rolls over after 1024 weeks.  This 
causes problems for GPS receivers that are 
more than a few years old since they have no idea what year it is.
The total number of seconds offset from UTC is transmitted separately so that a 
GPS receiver can display either GPS time 
or UTC.
Note that the time and position are independent from the year.

http://www.prc68.com/I/Trimpack.shtml#WkRlvr

-- 
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 
> Hi all,
>
> Was just listening to the CrowdScience on time. Thanks to whoever posted the 
> link to it.
>
> CrowdScience indicated that a leap second was not added for the GPS. They 
> also indicated that the GPS gives us UTC time.
>
> Question:
> The UTC time that the GPS gives. Does that have the leap second added?
>
> Thanks,
>
> Regards,
>
> Roderick Wall.
>
> - Reply message -
> From: "Michael Ossipoff" 
> To: "Robert Kellogg" 
> Cc: "sundial list" 
> Subject: Why we should reform the Calendar
> Date: Mon, Jan 30, 2017 8:00 AM
>
> On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
> wrote:
>
> > Michael goes off looking for the ideal tropical year
>
>
> There isn't an "ideal tropical year", but, as a choice for a
> leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
> best for year-round reduction of longterm calendar-drift.  ...and the
> average of the lengths of the March & September Equinox tropical years
> (I'll call that the Average Equinox Year (AEY) ) is a compromise between
> the vernal equinoxes of the North & the South.
>
>
> > , perhaps ignoring effects of the earth's nutations.
> >
>
> Of course. The nutations are small in amplitude & period. They aren't part
> of calendar rules. The mean equinox (nutations averaged-out) is the one
> that is meant when the equinox is spoken of with regard to calendars.
>
>
>
> > I'll still take the one of 1900, most importantly because it defines the
> > SI second.
>
>
> The SI second was defined as 1/86,400 of a mean solar day, for some year in
> the early 19th century. I don't remember exactly what year that was. 1820?
> 1840? 1850?
>
> Evidently it isn't practical to update the length of the SI second, but
> that doesn't mean that calendars have to be based on the ephemeris day, or
> atomic day, consisting of 86,400 SI seconds, when that's known to be
> different from today's mean solar day.
>
> That's why I suggest 365.24217 instead of 365.24219 for the length of the
> mean tropical year (MTYI. It makes sense to base a calendar leap-year
> rule's mean-year on the actual length of a tropical-year (whichever one we
> want to use) on the length of that tropical year in* today's* mean days.
>
>
> >
> >
> > So, contemplating changing the year is non trivial.
>
>
> Evidently there must be some reason why it would be impractical to update
> the length of the SI second. But it isn't necessary to call a MTY 365.24219
> days, when it's really 365.24217 mean days long.   ...for the purposes of a
> calendar leapyear rule. There's inevitable inaccuracy due to rounding-off,
> and due to gradual change in the lengths of all the tropical years,
> including the MTY. But that doesn't mean we have to intentionally add
> avoidable error.
>
>
>
> > Contemplating decoupling UTC from the rotation of the earth (ie necessity
> > of being within .9 sec of UT1) likewise has significant consequences.
> > Let's let the IAU chart the future of time.
>
>
> Sure, but it isn't necessary to base a calendar on a day that isn't today's
> mean solar day.
>
> Michael Ossipoff
>
>
>
>
>
> > Dennis and Ken, if you're listening to this discussion, please chime in.
> >
> >
> > On 1/29/2017 12:27 PM, sundial-requ...@uni-koeln.de wrote:
> >
> >> Send sundial mailing list submissions to
> >> sundial@uni-koeln.de
> >>
> >> To subscribe or unsubscribe via the World Wide Web, visit
> >>https://lists.uni-koeln.de/mailman/listinfo/sundial
> >> or, via email, send a message with subject or body 'help' to
> >> sundial-requ...@uni-koeln.de
> >>
> >> You can reach the person managing the list at
> >> sundial-ow...@uni-koeln.de
> >>
> >> When

Re: Time question on GPS TIME and leap second.

2017-01-30 Thread Richard Langley 
"This causes problems for GPS receivers that are more than a few years old 
since they have no idea what year it is."


Not quite true. One of the continuously operating receivers at UNB is more than 
15 years old. Please see:

http://gauss2.gge.unb.ca/gpsworld/gpsworld.november98.pdf​


-- Richard Langley


-
| Richard B. LangleyE-mail: l...@unb.ca |
| Geodetic Research Laboratory  Web: 
http://gge.unb.ca<http://gge.unb.ca/>  |
| Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
| University of New Brunswick   Fax:  +1 506 453-4943   |
| Fredericton, N.B., Canada  E3B 5A3|
|Fredericton?  Where's that?  See: 
http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
   |
-

From: sundial <sundial-boun...@uni-koeln.de> on behalf of Brooke Clarke 
<bro...@pacific.net>
Sent: Monday, January 30, 2017 4:29 PM
To: sundial list
Subject: Re: Time question on GPS TIME and leap second.

Hi Roderick:

GPS time is continuous, that's to say there are no leap seconds or other 
changes to it since it started.  It uses a 10 bit binary week counter so the 
week number rolls over after 1024 weeks.  This causes problems for GPS 
receivers that are more than a few years old since they have no idea what year 
it is.
The total number of seconds offset from UTC is transmitted separately so that a 
GPS receiver can display either GPS time or UTC.
Note that the time and position are independent from the year.

http://www.prc68.com/I/Trimpack.shtml#WkRlvr

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html


 Original Message 
Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" <email9648...@gmail.com><mailto:email9648...@gmail.com>
To: "Robert Kellogg" <rkell...@comcast.net><mailto:rkell...@comcast.net>
Cc: "sundial list" <sundial@uni-koeln.de><mailto:sundial@uni-koeln.de>
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM


On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
<rkell...@comcast.net><mailto:rkell...@comcast.net>
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I don't remember exactly what year that was. 1820?
1840? 1850?

Evidently it isn't practical to update the length of the SI second, but
that doesn't mean that calendars have to be based on the ephemeris day, or
atomic day, consisting of 86,400 SI seconds, when that's known to be
different from today's mean solar day.

That's why I suggest 365.24217 instead of 365.24219 for the length of the
mean tropical year (MTYI. It makes sense to base a calendar leap-year
rule's mean-year on the actual length of a tropical-year (whichever one we
want to use) on the length of that tropical year in* today's* mean days.


>
>
> So, contemplating changing the year is non trivial.


Evidently there must be some reason why it would be impractical to update
the length of the SI second. But it isn't necessary to call a MTY 365.24219
days, when it's really 365.24217 mean days long.   ...for the purposes of a
calendar leapyear rule. There's inevitable inaccuracy due to rounding-off,
and due to gradual change in the lengths of all the tropical years,
including the MTY. But that doesn't mea

Re: Time question on GPS TIME and leap second.

2017-01-30 Thread Brooke Clarke 

Hi Roderick:

GPS time is continuous, that's to say there are no leap seconds or other changes to it since it started.  It uses a 10 
bit binary week counter so the week number rolls over after 1024 weeks.  This causes problems for GPS receivers that are 
more than a few years old since they have no idea what year it is.
The total number of seconds offset from UTC is transmitted separately so that a GPS receiver can display either GPS time 
or UTC.

Note that the time and position are independent from the year.

http://www.prc68.com/I/Trimpack.shtml#WkRlvr

--
Have Fun,

Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html

 Original Message 

Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" 
To: "Robert Kellogg" 
Cc: "sundial list" 
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM

On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I don't remember exactly what year that was. 1820?
1840? 1850?

Evidently it isn't practical to update the length of the SI second, but
that doesn't mean that calendars have to be based on the ephemeris day, or
atomic day, consisting of 86,400 SI seconds, when that's known to be
different from today's mean solar day.

That's why I suggest 365.24217 instead of 365.24219 for the length of the
mean tropical year (MTYI. It makes sense to base a calendar leap-year
rule's mean-year on the actual length of a tropical-year (whichever one we
want to use) on the length of that tropical year in* today's* mean days.


>
>
> So, contemplating changing the year is non trivial.


Evidently there must be some reason why it would be impractical to update
the length of the SI second. But it isn't necessary to call a MTY 365.24219
days, when it's really 365.24217 mean days long.   ...for the purposes of a
calendar leapyear rule. There's inevitable inaccuracy due to rounding-off,
and due to gradual change in the lengths of all the tropical years,
including the MTY. But that doesn't mean we have to intentionally add
avoidable error.



> Contemplating decoupling UTC from the rotation of the earth (ie necessity
> of being within .9 sec of UT1) likewise has significant consequences.
> Let's let the IAU chart the future of time.


Sure, but it isn't necessary to base a calendar on a day that isn't today's
mean solar day.

Michael Ossipoff





> Dennis and Ken, if you're listening to this discussion, please chime in.
>
>
> On 1/29/2017 12:27 PM, sundial-requ...@uni-koeln.de wrote:
>
>> Send sundial mailing list submissions to
>> sundial@uni-koeln.de
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>>https://lists.uni-koeln.de/mailman/listinfo/sundial
>> or, via email, send a message with subject or body 'help' to
>> sundial-requ...@uni-koeln.de
>>
>> You can reach the person managing the list at
>> sundial-ow...@uni-koeln.de
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of sundial digest..."
>>
>>
>> Today's Topics:
>>
>> 1. Re: Why we should reform the Calendar (Michael Ossipoff)
>>
>>
>> --
>>
>> Message: 1
>> Date: Sun, 29 Jan 2017 12:27:56 -0500
>> From: Michael Ossipoff 
>> To: Dan-George Uza 
>> Cc: sundial list 
>> Subject: Re: Why we should reform the Calendar
>> Message-ID:
>> > gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>>
>> Here are two (unimportant) objections to the

Re: Time question on GPS TIME and leap second.

2017-01-29 Thread Richard Langley 
Here is a link to an old GPS World article on GPS and the leap second:

http://www2.unb.ca/gge/Resources/gpsworld.november99.pdf

See the "The GPS Navigation Message" sidebar in particular.

And an article from GPS World on the occasion of the previous leap second:

http://gpsworld.com/its-leap-second-day-time-to-get-in-sync/


-- Richard Langley


-
| Richard B. LangleyE-mail: l...@unb.ca |
| Geodetic Research Laboratory  Web: 
http://gge.unb.ca<http://gge.unb.ca/>  |
| Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142   |
| University of New Brunswick   Fax:  +1 506 453-4943   |
| Fredericton, N.B., Canada  E3B 5A3|
|Fredericton?  Where's that?  See: 
http://www.fredericton.ca/<https://unbmail.unb.ca/owa/redir.aspx?C=tVxi5OaRXE2jUmSNTu0wE7USusV6L9AIh-TKOqhq1DE--EjKeq-SUal8Myg-FGJn53Gm890SFIc.=http%3a%2f%2fwww.fredericton.ca%2f>
   |
-

From: sundial <sundial-boun...@uni-koeln.de> on behalf of Richard Langley 
<l...@unb.ca>
Sent: Sunday, January 29, 2017 7:02 PM
To: rodwall1...@gmail.com
Cc: sundial list
Subject: Re: Time question on GPS TIME and leap second.

Yes. The navigation message transmitted by GPS satellites includes the current 
leap second offset so a receiver can compute and display correct UTC.

-- Richard Langley

Sent from my iPhone

On Jan 29, 2017, at 6:05 PM, 
rodwall1...@gmail.com<mailto:rodwall1...@gmail.com> 
<rodwall1...@gmail.com<mailto:rodwall1...@gmail.com>> wrote:

Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" <email9648...@gmail.com<mailto:email9648...@gmail.com>>
To: "Robert Kellogg" <rkell...@comcast.net<mailto:rkell...@comcast.net>>
Cc: "sundial list" <sundial@uni-koeln.de<mailto:sundial@uni-koeln.de>>
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM


On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
<rkell...@comcast.net<mailto:rkell...@comcast.net>>
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I don't remember exactly what year that was. 1820?
1840? 1850?

Evidently it isn't practical to update the length of the SI second, but
that doesn't mean that calendars have to be based on the ephemeris day, or
atomic day, consisting of 86,400 SI seconds, when that's known to be
different from today's mean solar day.

That's why I suggest 365.24217 instead of 365.24219 for the length of the
mean tropical year (MTYI. It makes sense to base a calendar leap-year
rule's mean-year on the actual length of a tropical-year (whichever one we
want to use) on the length of that tropical year in* today's* mean days.


>
>
> So, contemplating changing the year is non trivial.


Evidently there must be some reason why it would be impractical to update
the length of the SI second. But it isn't necessary to call a MTY 365.24219
days, when it's really 365.24217 mean days long.   ...for the purposes of a
calendar leapyear rule. There's inevitable inaccuracy due to rounding-off,
and due to gradual change in the lengths of all the tropical years,
including the MTY. But that doesn't mean we have to intentionally add
avoidable error.



> Contemplating decoupling UTC from the rotation of the earth (ie necessity
> of being within .9 sec of UT1) likewise has significant consequences.
> Let's let the IAU chart the future of time.


Sure, but it isn't necessary to

Re: Time question on GPS TIME and leap second.

2017-01-29 Thread Richard Langley 
Yes. The navigation message transmitted by GPS satellites includes the current 
leap second offset so a receiver can compute and display correct UTC.

-- Richard Langley

Sent from my iPhone

On Jan 29, 2017, at 6:05 PM, 
rodwall1...@gmail.com 
> wrote:

Hi all,

Was just listening to the CrowdScience on time. Thanks to whoever posted the 
link to it.

CrowdScience indicated that a leap second was not added for the GPS. They also 
indicated that the GPS gives us UTC time.

Question:
The UTC time that the GPS gives. Does that have the leap second added?

Thanks,

Regards,

Roderick Wall.

- Reply message -
From: "Michael Ossipoff" >
To: "Robert Kellogg" >
Cc: "sundial list" >
Subject: Why we should reform the Calendar
Date: Mon, Jan 30, 2017 8:00 AM


On Sun, Jan 29, 2017 at 2:41 PM, Robert Kellogg 
>
wrote:

> Michael goes off looking for the ideal tropical year


There isn't an "ideal tropical year", but, as a choice for a
leapyear-rule's mean-year, the length of the mean tropical year (MTY) is
best for year-round reduction of longterm calendar-drift.  ...and the
average of the lengths of the March & September Equinox tropical years
(I'll call that the Average Equinox Year (AEY) ) is a compromise between
the vernal equinoxes of the North & the South.


> , perhaps ignoring effects of the earth's nutations.
>

Of course. The nutations are small in amplitude & period. They aren't part
of calendar rules. The mean equinox (nutations averaged-out) is the one
that is meant when the equinox is spoken of with regard to calendars.



> I'll still take the one of 1900, most importantly because it defines the
> SI second.


The SI second was defined as 1/86,400 of a mean solar day, for some year in
the early 19th century. I don't remember exactly what year that was. 1820?
1840? 1850?

Evidently it isn't practical to update the length of the SI second, but
that doesn't mean that calendars have to be based on the ephemeris day, or
atomic day, consisting of 86,400 SI seconds, when that's known to be
different from today's mean solar day.

That's why I suggest 365.24217 instead of 365.24219 for the length of the
mean tropical year (MTYI. It makes sense to base a calendar leap-year
rule's mean-year on the actual length of a tropical-year (whichever one we
want to use) on the length of that tropical year in* today's* mean days.


>
>
> So, contemplating changing the year is non trivial.


Evidently there must be some reason why it would be impractical to update
the length of the SI second. But it isn't necessary to call a MTY 365.24219
days, when it's really 365.24217 mean days long.   ...for the purposes of a
calendar leapyear rule. There's inevitable inaccuracy due to rounding-off,
and due to gradual change in the lengths of all the tropical years,
including the MTY. But that doesn't mean we have to intentionally add
avoidable error.



> Contemplating decoupling UTC from the rotation of the earth (ie necessity
> of being within .9 sec of UT1) likewise has significant consequences.
> Let's let the IAU chart the future of time.


Sure, but it isn't necessary to base a calendar on a day that isn't today's
mean solar day.

Michael Ossipoff





> Dennis and Ken, if you're listening to this discussion, please chime in.
>
>
> On 1/29/2017 12:27 PM, 
> sundial-requ...@uni-koeln.de wrote:
>
>> Send sundial mailing list submissions to
>> sundial@uni-koeln.de
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>> https://lists.uni-koeln.de/mailman/listinfo/sundial
>> or, via email, send a message with subject or body 'help' to
>> sundial-requ...@uni-koeln.de
>>
>> You can reach the person managing the list at
>> sundial-ow...@uni-koeln.de
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of sundial digest..."
>>
>>
>> Today's Topics:
>>
>> 1. Re: Why we should reform the Calendar (Michael Ossipoff)
>>
>>
>> --
>>
>> Message: 1
>> Date: Sun, 29 Jan 2017 12:27:56 -0500
>> From: Michael Ossipoff 
>> >
>> To: Dan-George Uza >
>> Cc: sundial list >
>> Subject: Re: Why we should reform the Calendar
>> Message-ID:
>> > gmail.com>
>> Content-Type: text/plain; charset="utf-8"
>>
>>
>> Here are two (unimportant)