Valentines Day & Love Numbers
Hi:
In the video about the Full Moon Curse (that's about measuring the distance to each of the 5 retro-reflectors on the
moon to 1 mm) there's a plot showing the elevation change in the Apache Point Observatory of about 20 inches peak to
peak. It's exactly the type of change the effects pendulum clocks.
I asked Tom Murphy if he used GPS to get the elevation plot and the answer is that it came from the gravitymeter with
the use of Love numbers.
http://en.wikipedia.org/wiki/Love_number <- has links to papers on Earth tides
Also see patent 3449956 and GWR instrument link at:
http://www.prc68.com/I/Pendulums.shtml
This means that the concrete piers where many Cesium clocks and GPS reference stations are located are bobbing up and
down as if they were on a ocean, although only tens of inches.
I think there was an earlier post saying this puts a limit (E-16?) on the ultimate quality of a clock because of it's
movement. I wonder if NIST has one of the GWR gravitymeters on a pier and uses that to discipline their fountain clocks
for the elevation change of the pier or if that's done for the GPS reference antennas?
--
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
I've seen this sort of thing many times before.
Don't be surprised if this goes the way of
AM stereo, etc.
Does anyone have any positive news about this?
Rick
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
LaCrosse 8055 is one of the few wall clocks I know that allows UTC time
zone to be selected.
BTW, I have a Casio Waveceptor watch (the cheap $30 one) and it works
excellently, always acquiring WWVB signal at midnight to 2 AM here on East
Coast.
On Wed, Feb 19, 2014 at 6:52 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
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and follow the instructions there.
Wouldn't that be nice!
They implement a new format which destroys much of the installed
infrastructure, then don't actually produce the 'better replacement'.
How very LORAN!
-John
==================
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
I've seen this sort of thing many times before.
Don't be surprised if this goes the way of
AM stereo, etc.
Does anyone have any positive news about this?
Rick
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Most of the "atomic" WWVB clocks cannot be set to zero time zone offset.
After considerable looking, I found one that can be set to GMT with DST
disabled. Look for this one:
Lacrosse Technology
Model WS-8016U
It also has local and RF remote temperature.
I got mine at Fry's Electronics, several years ago.
Larry
On 2/19/2014 3:52 PM, Richard (Rick) Karlquist wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
...
--
Best wishes,
Larry McDavid W6FUB
Anaheim, California (SE of Los Angeles, near Disneyland)
Radio Shack used to have one, they may still have it, I have one, it
works fine it has cca 2" tall numbers for the time, and 0.75" tall for
the datum and temperature, Fries Electronics is selling one for USD35.--
also
73
KJ6UJH
Alex
On 2/19/2014 4:10 PM, Tim Shoppa wrote:
LaCrosse 8055 is one of the few wall clocks I know that allows UTC time
zone to be selected.
BTW, I have a Casio Waveceptor watch (the cheap $30 one) and it works
excellently, always acquiring WWVB signal at midnight to 2 AM here on East
Coast.
On Wed, Feb 19, 2014 at 6:52 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
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and follow the instructions there.
I bought the MFJ 121-B. Not LED, but I wasn't looking for that option.
73, Dick, W1KSZ
On 2/19/2014 4:52 PM, Richard (Rick) Karlquist wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
actually they are supposed to have general availability by the end of Q1.
Will see and have no idea about the cost.
Not keeping my fingers crossed at all.
Regards
Paul.
On Wed, Feb 19, 2014 at 7:18 PM, J. Forster jfor@quikus.com wrote:
Wouldn't that be nice!
They implement a new format which destroys much of the installed
infrastructure, then don't actually produce the 'better replacement'.
How very LORAN!
-John
==================
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
I've seen this sort of thing many times before.
Don't be surprised if this goes the way of
AM stereo, etc.
Does anyone have any positive news about this?
Rick
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
Thanks for the suggestions, but the MFJ121 does not
display the date and the Lacrosse 8055 and 8016
do not display seconds. I need hour minutes seconds
day and date. You wouldn't think that would be
so hard. It looks like my only choice is this
smallish "wall" clock (more like a desk clock):
LaCrosse WS-8005U-W
The seconds are in rather small type.
I also do not need temperature, but I'm
stuck with it apparently.
All the really large clocks I have seen do not do GMT.
You know this right away when they have a time zone
map on the display.
Rick
Definitely avoid BRG clocks. They are reasonably priced and look really
nice on the outside but look like a high school science project inside.
Plus, with both versions I purchased (while at 2 different companies),
the IRIG-B option just didn't work reliably. It worked some of the
time, just enough to make you think it was working. Finally, the menu
system is confusing at best. Just say no...
-Bob
On 02/19/2014 05:52 PM, Richard (Rick) Karlquist wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
I recently bought a La Crosse, See at ebay item 360752857574, that quickly
synced up to WWVB and, at least to my ability to mark a time tick, been
within the second of WWV. Total cost was $43.
Michael / K7HIL
On Wed, Feb 19, 2014 at 4:52 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
time-nuts mailing list -- time-nuts@febo.com
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mailman/listinfo/time-nuts
and follow the instructions there.
On Wed, Feb 19, 2014 at 3:52 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC?
Any reason why it was to by WWVB? What if it used some other means of
saying accurate? The larger professional quality clocks generally don't
use WWVB. If you can relax your requirements more options are open.
Someone asked for this a while back and I think the simplest solution was
to use a cell phone app. You can buy a way-cheap android tablet, even a
used one and run a clock app on it. Some of them even simulate the red
LEDs you are looking for. It will remain accurate to better than your
eyes can detect.
--
Chris Albertson
Redondo Beach, California
Rick wrote:
"Thanks for the suggestions, but the MFJ121 does not
display the date"
The MFJ-121 might not include the date, but some of their other large WWVB
clocks do. Go to
http://www.mfjenterprises.com/Categories.php?sec=226(clock products)
and click on the ones that say "ATOMIC". I am not sure if
they all can be set to UTC but some of them say they can. MFJ products are
made for radio amateurs, many of whom use UTC for 'talking around the
world'.
Be aware that MFJ has mixed reviews ... some of their products that they
themselves assemble in Mississippi can have QC issues. Cold solder joints
is the one I hear most often. Some people love 'em; others hate 'em. They
are a successful business for 40+ years so I'd have to guess the lovers
outweigh the haters.
Andy
On 2/19/2014 6:35 PM, Chris Albertson wrote:
On Wed, Feb 19, 2014 at 3:52 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC?
Any reason why it was to by WWVB? What if it used some other means of
saying accurate? The larger professional quality clocks generally don't
Non technical reason.
I want to use WWVB because I want to be able to
mention to visitors that the clock links to an ensemble
of 5071A cesium standards, and I was one of the designers
of the 5071A, the actual atomic clock. I do also
want to use the clock for my ham station.
Rick
Brooke,
See old posting: http://www.febo.com/pipermail/time-nuts/2011-January/053478.html
The effect is too small (~5e-17 over 6 hours) to affect GPS time transfer.
/tvb
On Feb 19, 2014, at 8:24 AM, Brooke Clarke brooke@pacific.net wrote:
Hi:
In the video about the Full Moon Curse (that's about measuring the distance to each of the 5 retro-reflectors on the moon to 1 mm) there's a plot showing the elevation change in the Apache Point Observatory of about 20 inches peak to peak. It's exactly the type of change the effects pendulum clocks.
I asked Tom Murphy if he used GPS to get the elevation plot and the answer is that it came from the gravitymeter with the use of Love numbers.
http://en.wikipedia.org/wiki/Love_number <- has links to papers on Earth tides
Also see patent 3449956 and GWR instrument link at:
http://www.prc68.com/I/Pendulums.shtml
This means that the concrete piers where many Cesium clocks and GPS reference stations are located are bobbing up and down as if they were on a ocean, although only tens of inches.
I think there was an earlier post saying this puts a limit (E-16?) on the ultimate quality of a clock because of it's movement. I wonder if NIST has one of the GWR gravitymeters on a pier and uses that to discipline their fountain clocks for the elevation change of the pier or if that's done for the GPS reference antennas?
--
Have Fun,
Brooke Clarke
http://www.PRC68.com
http://www.end2partygovernment.com/2012Issues.html
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
On 2/19/14 10:24 AM, Brooke Clarke wrote:
Hi:
This means that the concrete piers where many Cesium clocks and GPS
reference stations are located are bobbing up and down as if they were
on a ocean, although only tens of inches.
My GPS friends comment when you start getting to sub-meter precision for
non-differential measurements, there's a whole lot of effects that start
getting in the way. ionosphere, multipath, solid earth tides, etc.
They're all in the "centimeters but not meters" bucket.
I think there was an earlier post saying this puts a limit (E-16?) on
the ultimate quality of a clock because of it's movement. I wonder if
NIST has one of the GWR gravitymeters on a pier and uses that to
discipline their fountain clocks for the elevation change of the pier or
if that's done for the GPS reference antennas?
CORRECTION:
The 8005 series (with indoor temperature) does not support GMT
Only the 8115 and 8119 series (with indoor and outdoor
temperature) support GMT.
On 2/19/2014 5:47 PM, Richard (Rick) Karlquist wrote:
so hard. It looks like my only choice is this
smallish "wall" clock (more like a desk clock):
LaCrosse WS-8005U-W
I guess my question is who has the right to grant "exclusive rights" for
the ability to decode a very simple protocol? Was a patent actually
granted for this?
John
On 2/19/2014 4:49 PM, Richard (Rick) Karlquist wrote:
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
I've seen this sort of thing many times before.
Don't be surprised if this goes the way of
AM stereo, etc.
Does anyone have any positive news about this?
Rick
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
On 2/19/2014 9:10 PM, John Marvin wrote:
I guess my question is who has the right to grant "exclusive rights" for
the ability to decode a very simple protocol? Was a patent actually
granted for this?
John
They have exclusive rights to the IP core for their IC.
I guess someone else could design their own IC...
Rick
From: Richard (Rick) Karlquist
Can anyone recommend a "atomic" wall clock
that displays in digital 24 hour UTC? Looking for largest
possible digits and LED preferred over LCD, under $100.
Any brands to avoid?
Rick
---=
Rick, you could make your own with a Raspberry Pi and TV:
http://www.satsignal.eu/raspberry-pi/DigitalClock.html
David
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor@blueyonder.co.uk
Or a discreet receiver using time-nut available stuff. NIST should be the
one that owns the format and they have published it.
Regards
Paul
On Thu, Feb 20, 2014 at 1:45 AM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
On 2/19/2014 9:10 PM, John Marvin wrote:
I guess my question is who has the right to grant "exclusive rights" for
the ability to decode a very simple protocol? Was a patent actually
granted for this?
John
They have exclusive rights to the IP core for their IC.
I guess someone else could design their own IC...
Rick
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Am Wed, 19 Feb 2014 22:45:56 -0800
schrieb "Richard (Rick) Karlquist" richard@karlquist.com:
On 2/19/2014 9:10 PM, John Marvin wrote:
I guess my question is who has the right to grant "exclusive
rights" for the ability to decode a very simple protocol? Was a
patent actually granted for this?
John
They have exclusive rights to the IP core for their IC.
I guess someone else could design their own IC...
Rick
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
Paul Swed posted a working, mostly analog, design here maybe 6 months ago.
-John
=============
Am Wed, 19 Feb 2014 22:45:56 -0800
schrieb "Richard (Rick) Karlquist" richard@karlquist.com:
On 2/19/2014 9:10 PM, John Marvin wrote:
I guess my question is who has the right to grant "exclusive
rights" for the ability to decode a very simple protocol? Was a
patent actually granted for this?
John
They have exclusive rights to the IP core for their IC.
I guess someone else could design their own IC...
Rick
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
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At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
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Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
On Thu, Feb 20, 2014 at 4:02 PM, Chuck Harris cfharris@erols.com wrote:
At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
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At least on the Atlantic coast, the WWVB signal levels jump all over the
place, certainly 40 dB and maybe more. If a receiver cannot deal w/ that
w/o losing lock, it's nearly useless.
OTOH, LORAN was always a whopping signal.
-John
================
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in
software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
On Thu, Feb 20, 2014 at 4:02 PM, Chuck Harris cfharris@erols.com wrote:
At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
time-nuts mailing list -- time-nuts@febo.com
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Totally agree with you John as I learned. I knew it was a variable but I
have seen nights that were crazy and do fit your 40 db. I redesigned the
AGC to account for that in the fr front end actually.
Regards
Paul
On Thu, Feb 20, 2014 at 4:34 PM, J. Forster jfor@quikus.com wrote:
At least on the Atlantic coast, the WWVB signal levels jump all over the
place, certainly 40 dB and maybe more. If a receiver cannot deal w/ that
w/o losing lock, it's nearly useless.
OTOH, LORAN was always a whopping signal.
-John
================
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in
software.
I responded and have had the great pleasure of communicating with
Matthias
over the last two weeks. I have learned a lot already and he in return
has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
On Thu, Feb 20, 2014 at 4:02 PM, Chuck Harris cfharris@erols.com
wrote:
At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
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The large amplitude swings happen on a very short time scale too.
Certainly <1 second at times.
-John
============
Totally agree with you John as I learned. I knew it was a variable but I
have seen nights that were crazy and do fit your 40 db. I redesigned the
AGC to account for that in the fr front end actually.
Regards
Paul
On Thu, Feb 20, 2014 at 4:34 PM, J. Forster jfor@quikus.com wrote:
At least on the Atlantic coast, the WWVB signal levels jump all over the
place, certainly 40 dB and maybe more. If a receiver cannot deal w/
that
w/o losing lock, it's nearly useless.
OTOH, LORAN was always a whopping signal.
-John
================
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in
software.
I responded and have had the great pleasure of communicating with
Matthias
over the last two weeks. I have learned a lot already and he in return
has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend
section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
On Thu, Feb 20, 2014 at 4:02 PM, Chuck Harris cfharris@erols.com
wrote:
At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much
chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out
of
range for a serious time nut ;-)
Florian
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Hi Paul,
could you give a hint how long ago you released the front end to T_N?
thanks
Neville Michie
(Sydney)
On 21/02/2014, at 8:29 AM, paul swed wrote:
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
On Thu, Feb 20, 2014 at 4:02 PM, Chuck Harris cfharris@erols.com wrote:
At 60KHz, it shouldn't be out of range of most
general purpose CPU's, and even the most pathetic DSP.
Why bother with a hardware solution when software can
do it more easily?
-Chuck Harris
Florian Teply wrote:
Well, if someone comes up with a circuit, I could check how much chip
area that would consume in a 250nm SiGe BiCMOS... Shouldn't be out of
range for a serious time nut ;-)
Florian
time-nuts mailing list -- time-nuts@febo.com
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On Thursday, February 20, 2014, J. Forster jfor@quikus.com wrote:
The large amplitude swings happen on a very short time scale too.
Certainly <1 second at times.
8-bits is 48 dB. 16-bit parts at 60kHz should be cheap now. Why bother with
AGC? Just make sure the ADC doesn't clip.
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706 Flightline Drive
Spring Branch, TX 78070
brian@lloyd.com
+1.916.877.5067
Hi Paul,
how was that 60kHz RF front end made I was not wit the group six months
ego could you please send me a copy/
thank you in advance
73
KJ6UHN
Alex
On 2/20/2014 1:29 PM, paul swed wrote:
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
Hi
You can get parts in the 18 bit and up range for not a whole lot of money with rational sample rates for a WWVB receiver. Analog Devices and Linear Tech both make some interesting looking parts. They get you into the >=100 db dynamic range area.
Even with a lower bit count part, you pick up some bits in the downsampling process. As long as you have enough noise to keep things moving, you can track pretty far down into the crud. GPS receivers do that sort of thing all the time.
Since this is slow audio after the CIC decimator, things like ARM chips probably have enough DSP horsepower to do what you need to do. The decimator it’s self is not terribly taxing if you don’t go too crazy with the rate change.
Bob
On Feb 20, 2014, at 7:40 PM, Brian Lloyd brian@lloyd.com wrote:
On Thursday, February 20, 2014, J. Forster jfor@quikus.com wrote:
The large amplitude swings happen on a very short time scale too.
Certainly <1 second at times.
8-bits is 48 dB. 16-bit parts at 60kHz should be cheap now. Why bother with
AGC? Just make sure the ADC doesn't clip.
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
--
Brian Lloyd, WB6RQN/J79BPL
706 Flightline Drive
Spring Branch, TX 78070
brian@lloyd.com
+1.916.877.5067
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Request sent offline.
Regards
Paul
On Thu, Feb 20, 2014 at 9:32 PM, Alex Pummer alex@pcscons.com wrote:
Hi Paul,
how was that 60kHz RF front end made I was not wit the group six months
ego could you please send me a copy/
thank you in advance
73
KJ6UHN
Alex
On 2/20/2014 1:29 PM, paul swed wrote:
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in
software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
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and follow the instructions there.
I am wondering if it's a tough road to get precise time and frequency.
I have a Kenwood TS-940S transceiver that can receive 60 kHz but I have never heard anything I could guess would be WWVB, just a fair amount of noise. I did calibrate against 20 MHz WWV so that the beat was one every several seconds. Not bad but I think it can be better.
I would love to discipline my counter and signal generator time bases to match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find it.
Bob
On Thursday, February 20, 2014 7:20 PM, paul swed paulswedb@gmail.com wrote:
Request sent offline.
Regards
Paul
On Thu, Feb 20, 2014 at 9:32 PM, Alex Pummer alex@pcscons.com wrote:
Hi Paul,
how was that 60kHz RF front end made I was not wit the group six months
ego could you please send me a copy/
thank you in advance
73
KJ6UHN
Alex
On 2/20/2014 1:29 PM, paul swed wrote:
Chuck thats easy. Because I could make it work. :-)
That said there was a post on time-nuts about LORAN C receiver in
software.
I responded and have had the great pleasure of communicating with Matthias
over the last two weeks. I have learned a lot already and he in return has
a tested LORAN C receiver.
So with some luck just maybe I can become smart enough to do a better
design in software on a $15 micro. You still need the RF frontend section
that I released quite a while ago to time-nuts.
Regards
Paul
WB8TSL
time-nuts mailing list -- time-nuts@febo.com
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mailman/listinfo/time-nuts
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I have a Kenwood TS-940S transceiver that can receive 60 kHz but I have never heard anything
Where are you? It must be deaf as a post.
I can hear WWVB in Australia !
(or at least I could till JJY-60 started in 2001)
........... Zim
On 2/20/14 4:40 PM, Brian Lloyd wrote:
On Thursday, February 20, 2014, J. Forster jfor@quikus.com wrote:
The large amplitude swings happen on a very short time scale too.
Certainly <1 second at times.
8-bits is 48 dB. 16-bit parts at 60kHz should be cheap now. Why bother with
AGC? Just make sure the ADC doesn't clip.
I sample at 100 kHz with 16 bits on a teensy3..
that is perhaps another 60kHz station they have one in England too!
73
KJ6HN
Alex
On 2/20/2014 8:35 PM, Graeme Zimmer wrote:
I have a Kenwood TS-940S transceiver that can receive 60 kHz but I
have never heard anything
Where are you? It must be deaf as a post.
I can hear WWVB in Australia !
(or at least I could till JJY-60 started in 2001)
........... Zim
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On 2/19/2014 8:47 PM, Richard (Rick) Karlquist wrote:
Thanks for the suggestions, but the MFJ121 does not
display the date and the Lacrosse 8055 and 8016
do not display seconds. I need hour minutes seconds
day and date. You wouldn't think that would be
so hard. It looks like my only choice is this
smallish "wall" clock (more like a desk clock):
How about a cheap Android tablet and a clock application? I assume
you're planning on AC power, since LEDs won't run long on battery.
Sellout.woot.com has a $60 tablet, and it's not hard to find them under
$100. According to the manual, "If Sero 7 connected with a Wi-Fi, you
can also select use network-provided time." While not strictly WWVB, if
you only need 1 second resolution, NTP should be fine. This also assumes
you have WiFi available.
You can probably find a 10" one for <$100. If you stretch, I've seen
refurb 1st gen iPads for $150 (pretty sure these can do NTP, too). The
real cheap tablets tend to have poor digitizers, but that really doesn't
matter for use as a wall clock.
http://sellout.woot.com
http://hisense-usa.com/tablets/sero7lt
https://play.google.com/store/apps/details?id=com.gadgetjuice.dockclock
On Fri, Feb 21, 2014 at 6:18 AM, Mike S mikes@flatsurface.com wrote:
How about a cheap Android tablet and a clock application? I assume you're
planning on AC power, since LEDs won't run long on battery....
I've seen refurb 1st gen iPads for $150 (pretty sure these can do NTP,
too). The real cheap tablets tend to have poor digitizers, but that really
doesn't matter for use as a wall clock.
For security purposes applications are not allowed to set system time.
Given "root" access you can do this so the simplest approach is run an NTP
display application.
However if an iPad is within financial reach and NTP meets the 5071
requirement then Emerald Time may an answer. Emerald Sequoia is invested
in horology if not metrology so they may be of some interest to a time nut.
I've attached a relevant screen capture and other images can be seen on
their App Store page. The fractional offset in the upper right is the NTP
delta. The main display is NTP time.
On the Android side I use clockSync which will set the system clock given
root access otherwise it just displays "Atomic" time and system time. It
doesn't have UTC mode so you'd have run the device in UTC. Screenshot also
attached.
Many ham transceivers can tune that low, but they are indeed completely deaf because the input filter (including coupling transformer) takes most of the signal out and the phase noise of the synthesizers cover the rest in noise.
Didier KO4BB
On February 20, 2014 10:35:06 PM CST, Graeme Zimmer gzimmer@wideband.net.au wrote:
I have a Kenwood TS-940S transceiver that can receive 60 kHz but I
have never heard anything
Where are you? It must be deaf as a post.
I can hear WWVB in Australia !
(or at least I could till JJY-60 started in 2001)
........... Zim
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--
Sent from my Motorola Droid Razr 4G LTE wireless tracker while I do other things.
At work we have various models of these "Selena" LED clock displays in the
new control center and dispatching rooms:
http://www.ledclocks.com/SELENA4x7.pdf
We use the "bare unit" which just has a Cat5 Ethernet jack that syncs to a
NTP clock on the network, but they also list options for WWVB, DCF77,
various IRIG variants, etc. I have never priced these options.
The TrueTime IRIG LED clock displays also show up quite regularly on E-bay
etc. if you already have something to generate the IRIG clock (and I'm
guessing you have that somewhere Rick! All of our IRIG timecode generators
are HP and/or Agilent if I remember.).
Tim N3QE
On Wed, Feb 19, 2014 at 6:49 PM, Richard (Rick) Karlquist <
richard@karlquist.com> wrote:
It may be true that WWVB is sending out a new
format, but the receivers for it don't seem to
exist. The exclusive rights are held by this
company, which is clearly on hold while it
tries to find a customer who will pay for a
wafer run:
I've seen this sort of thing many times before.
Don't be surprised if this goes the way of
AM stereo, etc.
Does anyone have any positive news about this?
Rick
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Bob,
If you are looking for an accurate, easy to use timing signal then GPS
is the one you want. WWV and WWVB are what I call "legacy" signals
and while they might be accurate when broadcast there is propagation
delay and unknown atmospheric and ionospheric conditions.
But the question is "How accurate do you need?" If a few tens of
milliseconds is good enough then running NTP over the internet will
work and if you already have an internet connection it's free. If you
need a few nanoseconds then GPS is what you want.
Using your beat with WWV as a benchmark. You were getting about one
part in a million accuracy. It is VERY easy to do 10,000 times better
than that with GPS.
On Thu, Feb 20, 2014 at 8:19 PM, Bob Albert bob91343@yahoo.com wrote:
I would love to discipline my counter and signal generator time bases to match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find it.
--
Chris Albertson
Redondo Beach, California
Boy do I need to agree with Chris's comments above. If this is anything
serious GPS really is the answer in all respects. Yes there is the risk of
something happening. But amazingly a lot of the GPS receivers hold onto
time pretty well even without GPS.
The whole WWVB thing makes sense as a frequency transfer method. But is not
at all close to GPS today. Its far more interesting to watch the VLF
propagation behaviors and as a sort of backup frequency reference. LORAN C
simply kicked butt with what it delivered and was on par with and frankly
better then GPS for frequency. At least for me over 20 years of practice.
But one day soon eLORAN may just come back its looking positive.
Sorry not to change the subject.
Regards
Paul.
On Fri, Feb 21, 2014 at 11:46 AM, Chris Albertson <albertson.chris@gmail.com
wrote:
Bob,
If you are looking for an accurate, easy to use timing signal then GPS
is the one you want. WWV and WWVB are what I call "legacy" signals
and while they might be accurate when broadcast there is propagation
delay and unknown atmospheric and ionospheric conditions.
But the question is "How accurate do you need?" If a few tens of
milliseconds is good enough then running NTP over the internet will
work and if you already have an internet connection it's free. If you
need a few nanoseconds then GPS is what you want.
Using your beat with WWV as a benchmark. You were getting about one
part in a million accuracy. It is VERY easy to do 10,000 times better
than that with GPS.
On Thu, Feb 20, 2014 at 8:19 PM, Bob Albert bob91343@yahoo.com wrote:
I would love to discipline my counter and signal generator time bases to
match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find it.
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
On Fri, Feb 21, 2014 at 7:02 AM, Paul tic-toc@bodosom.net wrote:
On Fri, Feb 21, 2014 at 6:18 AM, Mike S mikes@flatsurface.com wrote:
However if an iPad is within financial reach and NTP meets the 5071
requirement then Emerald Time may an answer. Emerald Sequoia is invested
in horology if not metrology so they may be of some interest to a time nut.
That works well. But as of a few years ago all Apple IOS devices
already have NTP built-in. But to conserve battery power NTP is not
run very often, just enough to keep the seconds digit read correctly.
Today any mobile device you have is likely to be as good or better
then a WWWV sync'd "atomic clock". There is not much reason to buy
one of those any more.
--
Chris Albertson
Redondo Beach, California
I looked on line and it seems that these receivers are available for about $150 and up. A little out of my price range right now but I'll keep my eyes open.
I presume that with a reasonable antenna this unit will give me a very precise 10 MHz which I can use to synchronize my counter. I am not sure if my counter will accept that frequency but it shouldn't be a big deal to convert to something it will accept, or use its OCXO as a transfer standard.
Bob
On Friday, February 21, 2014 8:57 AM, paul swed paulswedb@gmail.com wrote:
Boy do I need to agree with Chris's comments above. If this is anything
serious GPS really is the answer in all respects. Yes there is the risk of
something happening. But amazingly a lot of the GPS receivers hold onto
time pretty well even without GPS.
The whole WWVB thing makes sense as a frequency transfer method. But is not
at all close to GPS today. Its far more interesting to watch the VLF
propagation behaviors and as a sort of backup frequency reference. LORAN C
simply kicked butt with what it delivered and was on par with and frankly
better then GPS for frequency. At least for me over 20 years of practice.
But one day soon eLORAN may just come back its looking positive.
Sorry not to change the subject.
Regards
Paul.
On Fri, Feb 21, 2014 at 11:46 AM, Chris Albertson <albertson.chris@gmail.com
wrote:
Bob,
If you are looking for an accurate, easy to use timing signal then GPS
is the one you want. WWV and WWVB are what I call "legacy" signals
and while they might be accurate when broadcast there is propagation
delay and unknown atmospheric and ionospheric conditions.
But the question is "How accurate do you need?" If a few tens of
milliseconds is good enough then running NTP over the internet will
work and if you already have an internet connection it's free. If you
need a few nanoseconds then GPS is what you want.
Using your beat with WWV as a benchmark. You were getting about one
part in a million accuracy. It is VERY easy to do 10,000 times better
than that with GPS.
On Thu, Feb 20, 2014 at 8:19 PM, Bob Albert bob91343@yahoo.com wrote:
I would love to discipline my counter and signal generator time bases to
match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find it.
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
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Bob
Yes they will. But there is a danger here when you say very precise. On
Time-Nuts those are very particular words that can carry a very long email
thread.
You say that the complete solutions are a bit out of range.
Today there are lots of solutions if you want use a soldering iron.
Each has the trade off of cost effort and accuracy. But say you needed
something for amateur radio purposes pretty much any of the solutions are
very good.
Regards
Paul.
On Fri, Feb 21, 2014 at 12:47 PM, Bob Albert bob91343@yahoo.com wrote:
I looked on line and it seems that these receivers are available for about
$150 and up. A little out of my price range right now but I'll keep my
eyes open.
I presume that with a reasonable antenna this unit will give me a very
precise 10 MHz which I can use to synchronize my counter. I am not sure if
my counter will accept that frequency but it shouldn't be a big deal to
convert to something it will accept, or use its OCXO as a transfer standard.
Bob
On Friday, February 21, 2014 8:57 AM, paul swed paulswedb@gmail.com
wrote:
Boy do I need to agree with Chris's comments above. If this is anything
serious GPS really is the answer in all respects. Yes there is the risk of
something happening. But amazingly a lot of the GPS receivers hold onto
time pretty well even without GPS.
The whole WWVB thing makes sense as a frequency transfer method. But is not
at all close to GPS today. Its far more interesting to watch the VLF
propagation behaviors and as a sort of backup frequency reference. LORAN C
simply kicked butt with what it delivered and was on par with and frankly
better then GPS for frequency. At least for me over 20 years of practice.
But one day soon eLORAN may just come back its looking positive.
Sorry not to change the subject.
Regards
Paul.
On Fri, Feb 21, 2014 at 11:46 AM, Chris Albertson <
albertson.chris@gmail.com
wrote:
Bob,
If you are looking for an accurate, easy to use timing signal then GPS
is the one you want. WWV and WWVB are what I call "legacy" signals
and while they might be accurate when broadcast there is propagation
delay and unknown atmospheric and ionospheric conditions.
But the question is "How accurate do you need?" If a few tens of
milliseconds is good enough then running NTP over the internet will
work and if you already have an internet connection it's free. If you
need a few nanoseconds then GPS is what you want.
Using your beat with WWV as a benchmark. You were getting about one
part in a million accuracy. It is VERY easy to do 10,000 times better
than that with GPS.
On Thu, Feb 20, 2014 at 8:19 PM, Bob Albert bob91343@yahoo.com wrote:
I would love to discipline my counter and signal generator time bases
to
match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find
it.
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
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and follow the instructions there.
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To unsubscribe, go to
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Back to basics, please. Just how does GPS achieve its precision and accuracy?
I presume everything must relate to NIST eventually.
Bob
On Friday, February 21, 2014 10:04 AM, paul swed paulswedb@gmail.com wrote:
Bob
Yes they will. But there is a danger here when you say very precise. On Time-Nuts those are very particular words that can carry a very long email thread.
You say that the complete solutions are a bit out of range.
Today there are lots of solutions if you want use a soldering iron.
Each has the trade off of cost effort and accuracy. But say you needed something for amateur radio purposes pretty much any of the solutions are very good.
Regards
Paul.
On Fri, Feb 21, 2014 at 12:47 PM, Bob Albert bob91343@yahoo.com wrote:
I looked on line and it seems that these receivers are available for about $150 and up. A little out of my price range right now but I'll keep my eyes open.
I presume that with a reasonable antenna this unit will give me a very precise 10 MHz which I can use to synchronize my counter. I am not sure if my counter will accept that frequency but it shouldn't be a big deal to convert to something it will accept, or use its OCXO as a transfer standard.
Bob
On Friday, February 21, 2014 8:57 AM, paul swed paulswedb@gmail.com wrote:
Boy do I need to agree with Chris's comments above. If this is anything
serious GPS really is the answer in all respects. Yes there is the risk of
something happening. But amazingly a lot of the GPS receivers hold onto
time pretty well even without GPS.
The whole WWVB thing makes sense as a frequency transfer method. But is not
at all close to GPS today. Its far more interesting to watch the VLF
propagation behaviors and as a sort of backup frequency reference. LORAN C
simply kicked butt with what it delivered and was on par with and frankly
better then GPS for frequency. At least for me over 20 years of practice.
But one day soon eLORAN may just come back its looking positive.
Sorry not to change the subject.
Regards
Paul.
On Fri, Feb 21, 2014 at 11:46 AM, Chris Albertson <albertson.chris@gmail.com
wrote:
Bob,
If you are looking for an accurate, easy to use timing signal then GPS
is the one you want. WWV and WWVB are what I call "legacy" signals
and while they might be accurate when broadcast there is propagation
delay and unknown atmospheric and ionospheric conditions.
But the question is "How accurate do you need?" If a few tens of
milliseconds is good enough then running NTP over the internet will
work and if you already have an internet connection it's free. If you
need a few nanoseconds then GPS is what you want.
Using your beat with WWV as a benchmark. You were getting about one
part in a million accuracy. It is VERY easy to do 10,000 times better
than that with GPS.
On Thu, Feb 20, 2014 at 8:19 PM, Bob Albert bob91343@yahoo.com wrote:
I would love to discipline my counter and signal generator time bases to
match NIST. Is this possible, and what would I need to do?
I am sure this subject has been covered but I don't know how to find it.
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
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and follow the instructions there.
On Fri, Feb 21, 2014 at 9:47 AM, Bob Albert bob91343@yahoo.com wrote:
I looked on line and it seems that these receivers are available for about $150 and up. A little out of my price range right now but I'll keep my eyes open.
Watch the thread on this list about the Arduino based GPSDO. I think
you can get the price down to $50. If all you need is something to
calibrate frequency counter then all you need is 9 to 10 digit
accuracy
I'm going to do this just to prove it can be done for a low two figure
price. But first I have to find a decent crystal oscillator that does
not use up 1/2 of my $40 budget.
If you want ultimate precision that you need a good GPS antenna in a
good location, A high-end timing mode GPS receiver and a high-end
double oven quartz oscillator. The cost adds up. But I think if you
relax the specifications and shoot only for 9 to 10 digits you can
greatly reduce the price.
--
Chris Albertson
Redondo Beach, California
On Fri, Feb 21, 2014 at 12:23 PM, Chris Albertson <albertson.chris@gmail.com
wrote:
But as of a few years ago all Apple IOS devices
already have NTP built-in. But to conserve battery power NTP is not
run very often, just enough to keep the seconds digit read correctly.
Seconds!
But seriously my iPad2 is behind by two seconds, although the newer ones
track a bit better. My Android experience is not as good.
Of course the products I referred to don't actually run ntpd and they're
not disciplining the clock. Much like the titular WWVB "Atomic" clock they
periodically run the equivalent of ntpdate.