Empathy List Archives

GL

Glenn Little WB4UIV

Fri, Nov 13, 2009 6:13 AM

While I was in the US Navy we had two Cesium standards for the
navigation center on SSBN submarines.
While in port, we would track LORAN C and compute the drift rate of
the two cesium standards.
Is there a service, that has drift rates published, that I can
compare my standards to, so that I can determine the standard drift rate.
I do not remember the drift rates that we determined on the
submarine, that was a few years ago, but, I seem to remember that the
rate was in the low nanoseconds.
If a rubidium standard drifts in one direction (does it?) a drift
rate could be calculated and, after a comparison to a known standard,
with known drift rate, a very accurate standard could be had for the lab.

What would I expect the drift rate, or jitter, to be in a FRK class
rubidium oscillator?

Is the drift rate constant enough that a drift rate could be applied
to a rubidium oscillator to determine it's real frequency at any given time.

We calibrated the submarine Cesium standards every three months.
We had to know the drift rate of our standard as well as the drift
rate of the standard in each of the LORAN stations to be able to do
the type of LORAN navigation that we did.

I would like to be able to verify that my PTB-100 rubidium oscillator
is on frequency.

If I compare two rubidium oscillators, what would I expect the
relative drift rate to be?

Thanks
73
Glenn
WB4UIV

While I was in the US Navy we had two Cesium standards for the navigation center on SSBN submarines. While in port, we would track LORAN C and compute the drift rate of the two cesium standards. Is there a service, that has drift rates published, that I can compare my standards to, so that I can determine the standard drift rate. I do not remember the drift rates that we determined on the submarine, that was a few years ago, but, I seem to remember that the rate was in the low nanoseconds. If a rubidium standard drifts in one direction (does it?) a drift rate could be calculated and, after a comparison to a known standard, with known drift rate, a very accurate standard could be had for the lab. What would I expect the drift rate, or jitter, to be in a FRK class rubidium oscillator? Is the drift rate constant enough that a drift rate could be applied to a rubidium oscillator to determine it's real frequency at any given time. We calibrated the submarine Cesium standards every three months. We had to know the drift rate of our standard as well as the drift rate of the standard in each of the LORAN stations to be able to do the type of LORAN navigation that we did. I would like to be able to verify that my PTB-100 rubidium oscillator is on frequency. If I compare two rubidium oscillators, what would I expect the relative drift rate to be? Thanks 73 Glenn WB4UIV

BK

Brian Kirby

Fri, Nov 13, 2009 5:48 PM

You will need a receiver to compare your references to. It appears that
LORAN will be shut off, so that leaves two services available, either
WWV 60 Khz or GPS. I do not use WWV any more, I can tell you about GPS.

To compare against GPS you will need a timing receiver, there are
several available. A lot of us got Motorola Oncore VPs, UTs, or M12+,
The Rockwell Jupiter is one and there are several more. They provide a
1 PPS signal that is locked to the on board standards on the GPS
satellite. You put this signal in one input of a time interval
counter. You use a 1 PPS divider on your local reference and put its
signal in the other input of the time interval counter. You can record
continuous or take daily 24 hour readings and derive your drift rates.

GPS corrections are published at NIST;
http://tf.nist.gov/service/gpstrace.htm

You can also compare against a GPS disciplined oscillator. In the long
term it should be dead on, you will have to have it characterized for
the short term. The HP Z3801A was on the surplus market several years
back, its probably one of the best. The Trimble Thunderbolts were
available to the group a while back.

Brian KD4FM

Glenn Little WB4UIV wrote:

While I was in the US Navy we had two Cesium standards for the
navigation center on SSBN submarines.
While in port, we would track LORAN C and compute the drift rate of
the two cesium standards.
Is there a service, that has drift rates published, that I can compare
my standards to, so that I can determine the standard drift rate.
I do not remember the drift rates that we determined on the submarine,
that was a few years ago, but, I seem to remember that the rate was in
the low nanoseconds.
If a rubidium standard drifts in one direction (does it?) a drift rate
could be calculated and, after a comparison to a known standard, with
known drift rate, a very accurate standard could be had for the lab.

What would I expect the drift rate, or jitter, to be in a FRK class
rubidium oscillator?

Is the drift rate constant enough that a drift rate could be applied
to a rubidium oscillator to determine it's real frequency at any given
time.

We calibrated the submarine Cesium standards every three months.
We had to know the drift rate of our standard as well as the drift
rate of the standard in each of the LORAN stations to be able to do
the type of LORAN navigation that we did.

I would like to be able to verify that my PTB-100 rubidium oscillator
is on frequency.

If I compare two rubidium oscillators, what would I expect the
relative drift rate to be?

Thanks
73
Glenn
WB4UIV

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.

You will need a receiver to compare your references to. It appears that LORAN will be shut off, so that leaves two services available, either WWV 60 Khz or GPS. I do not use WWV any more, I can tell you about GPS. To compare against GPS you will need a timing receiver, there are several available. A lot of us got Motorola Oncore VPs, UTs, or M12+, The Rockwell Jupiter is one and there are several more. They provide a 1 PPS signal that is locked to the on board standards on the GPS satellite. You put this signal in one input of a time interval counter. You use a 1 PPS divider on your local reference and put its signal in the other input of the time interval counter. You can record continuous or take daily 24 hour readings and derive your drift rates. GPS corrections are published at NIST; http://tf.nist.gov/service/gpstrace.htm You can also compare against a GPS disciplined oscillator. In the long term it should be dead on, you will have to have it characterized for the short term. The HP Z3801A was on the surplus market several years back, its probably one of the best. The Trimble Thunderbolts were available to the group a while back. Brian KD4FM Glenn Little WB4UIV wrote: > While I was in the US Navy we had two Cesium standards for the > navigation center on SSBN submarines. > While in port, we would track LORAN C and compute the drift rate of > the two cesium standards. > Is there a service, that has drift rates published, that I can compare > my standards to, so that I can determine the standard drift rate. > I do not remember the drift rates that we determined on the submarine, > that was a few years ago, but, I seem to remember that the rate was in > the low nanoseconds. > If a rubidium standard drifts in one direction (does it?) a drift rate > could be calculated and, after a comparison to a known standard, with > known drift rate, a very accurate standard could be had for the lab. > > What would I expect the drift rate, or jitter, to be in a FRK class > rubidium oscillator? > > Is the drift rate constant enough that a drift rate could be applied > to a rubidium oscillator to determine it's real frequency at any given > time. > > We calibrated the submarine Cesium standards every three months. > We had to know the drift rate of our standard as well as the drift > rate of the standard in each of the LORAN stations to be able to do > the type of LORAN navigation that we did. > > I would like to be able to verify that my PTB-100 rubidium oscillator > is on frequency. > > If I compare two rubidium oscillators, what would I expect the > relative drift rate to be? > > Thanks > 73 > Glenn > WB4UIV > > > > > _______________________________________________ > 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. >

JF

J. Forster

Fri, Nov 13, 2009 5:51 PM

WWVB not WWV.

IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that LORAN
is being shut down.

-John

============

You will need a receiver to compare your references to. It appears that
LORAN will be shut off, so that leaves two services available, either
WWV 60 Khz or GPS. I do not use WWV any more, I can tell you about GPS.

To compare against GPS you will need a timing receiver, there are
several available. A lot of us got Motorola Oncore VPs, UTs, or M12+,
The Rockwell Jupiter is one and there are several more. They provide a
1 PPS signal that is locked to the on board standards on the GPS
satellite. You put this signal in one input of a time interval
counter. You use a 1 PPS divider on your local reference and put its
signal in the other input of the time interval counter. You can record
continuous or take daily 24 hour readings and derive your drift rates.

GPS corrections are published at NIST;
http://tf.nist.gov/service/gpstrace.htm

You can also compare against a GPS disciplined oscillator. In the long
term it should be dead on, you will have to have it characterized for
the short term. The HP Z3801A was on the surplus market several years
back, its probably one of the best. The Trimble Thunderbolts were
available to the group a while back.

Brian KD4FM

Glenn Little WB4UIV wrote:

While I was in the US Navy we had two Cesium standards for the
navigation center on SSBN submarines.
While in port, we would track LORAN C and compute the drift rate of
the two cesium standards.
Is there a service, that has drift rates published, that I can compare
my standards to, so that I can determine the standard drift rate.
I do not remember the drift rates that we determined on the submarine,
that was a few years ago, but, I seem to remember that the rate was in
the low nanoseconds.
If a rubidium standard drifts in one direction (does it?) a drift rate
could be calculated and, after a comparison to a known standard, with
known drift rate, a very accurate standard could be had for the lab.

What would I expect the drift rate, or jitter, to be in a FRK class
rubidium oscillator?

Is the drift rate constant enough that a drift rate could be applied
to a rubidium oscillator to determine it's real frequency at any given
time.

We calibrated the submarine Cesium standards every three months.
We had to know the drift rate of our standard as well as the drift
rate of the standard in each of the LORAN stations to be able to do
the type of LORAN navigation that we did.

I would like to be able to verify that my PTB-100 rubidium oscillator
is on frequency.

If I compare two rubidium oscillators, what would I expect the
relative drift rate to be?

Thanks
73
Glenn
WB4UIV

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.

WWVB not WWV. IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that LORAN is being shut down. -John ============ > You will need a receiver to compare your references to. It appears that > LORAN will be shut off, so that leaves two services available, either > WWV 60 Khz or GPS. I do not use WWV any more, I can tell you about GPS. > > To compare against GPS you will need a timing receiver, there are > several available. A lot of us got Motorola Oncore VPs, UTs, or M12+, > The Rockwell Jupiter is one and there are several more. They provide a > 1 PPS signal that is locked to the on board standards on the GPS > satellite. You put this signal in one input of a time interval > counter. You use a 1 PPS divider on your local reference and put its > signal in the other input of the time interval counter. You can record > continuous or take daily 24 hour readings and derive your drift rates. > > GPS corrections are published at NIST; > http://tf.nist.gov/service/gpstrace.htm > > You can also compare against a GPS disciplined oscillator. In the long > term it should be dead on, you will have to have it characterized for > the short term. The HP Z3801A was on the surplus market several years > back, its probably one of the best. The Trimble Thunderbolts were > available to the group a while back. > > Brian KD4FM > > Glenn Little WB4UIV wrote: >> While I was in the US Navy we had two Cesium standards for the >> navigation center on SSBN submarines. >> While in port, we would track LORAN C and compute the drift rate of >> the two cesium standards. >> Is there a service, that has drift rates published, that I can compare >> my standards to, so that I can determine the standard drift rate. >> I do not remember the drift rates that we determined on the submarine, >> that was a few years ago, but, I seem to remember that the rate was in >> the low nanoseconds. >> If a rubidium standard drifts in one direction (does it?) a drift rate >> could be calculated and, after a comparison to a known standard, with >> known drift rate, a very accurate standard could be had for the lab. >> >> What would I expect the drift rate, or jitter, to be in a FRK class >> rubidium oscillator? >> >> Is the drift rate constant enough that a drift rate could be applied >> to a rubidium oscillator to determine it's real frequency at any given >> time. >> >> We calibrated the submarine Cesium standards every three months. >> We had to know the drift rate of our standard as well as the drift >> rate of the standard in each of the LORAN stations to be able to do >> the type of LORAN navigation that we did. >> >> I would like to be able to verify that my PTB-100 rubidium oscillator >> is on frequency. >> >> If I compare two rubidium oscillators, what would I expect the >> relative drift rate to be? >> >> Thanks >> 73 >> Glenn >> WB4UIV >> >> >> >> >> _______________________________________________ >> 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 > and follow the instructions there. > >

PS

paul swed

Fri, Nov 13, 2009 6:08 PM

I use GPS and LORAN. Always nice to have a backup
With LORAN being shut down, have resurrected the ole wwvb rcvr and built an
amplified loop ant.
Can work but it takes about 3-5 hours to get to 1X10^11 accuracy. Still
observing various strange ness shuch as diurnal shift ...
Odd wwvb works at least for me most stable in the day. I seem to remember
night was supposed to be better.
The signal is much stronger at night.
So I guess its a play but sure not as easy as gud ole LORAN C has been.

On Fri, Nov 13, 2009 at 12:48 PM, Brian Kirby
kilodelta4foxmike@gmail.comwrote:

You will need a receiver to compare your references to. It appears that
LORAN will be shut off, so that leaves two services available, either WWV 60
Khz or GPS. I do not use WWV any more, I can tell you about GPS.

To compare against GPS you will need a timing receiver, there are several
available. A lot of us got Motorola Oncore VPs, UTs, or M12+, The Rockwell
Jupiter is one and there are several more. They provide a 1 PPS signal that
is locked to the on board standards on the GPS satellite. You put this
signal in one input of a time interval counter. You use a 1 PPS divider on
your local reference and put its signal in the other input of the time
interval counter. You can record continuous or take daily 24 hour readings
and derive your drift rates.

GPS corrections are published at NIST;
http://tf.nist.gov/service/gpstrace.htm

You can also compare against a GPS disciplined oscillator. In the long
term it should be dead on, you will have to have it characterized for the
short term. The HP Z3801A was on the surplus market several years back, its
probably one of the best. The Trimble Thunderbolts were available to the
group a while back.
Brian KD4FM

Glenn Little WB4UIV wrote:

While I was in the US Navy we had two Cesium standards for the navigation
center on SSBN submarines.
While in port, we would track LORAN C and compute the drift rate of the
two cesium standards.
Is there a service, that has drift rates published, that I can compare my
standards to, so that I can determine the standard drift rate.
I do not remember the drift rates that we determined on the submarine,
that was a few years ago, but, I seem to remember that the rate was in the
low nanoseconds.
If a rubidium standard drifts in one direction (does it?) a drift rate
could be calculated and, after a comparison to a known standard, with known
drift rate, a very accurate standard could be had for the lab.

What would I expect the drift rate, or jitter, to be in a FRK class
rubidium oscillator?

Is the drift rate constant enough that a drift rate could be applied to a
rubidium oscillator to determine it's real frequency at any given time.

We calibrated the submarine Cesium standards every three months.
We had to know the drift rate of our standard as well as the drift rate of
the standard in each of the LORAN stations to be able to do the type of
LORAN navigation that we did.

I would like to be able to verify that my PTB-100 rubidium oscillator is
on frequency.

If I compare two rubidium oscillators, what would I expect the relative
drift rate to be?

Thanks
73
Glenn
WB4UIV

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.

I use GPS and LORAN. Always nice to have a backup With LORAN being shut down, have resurrected the ole wwvb rcvr and built an amplified loop ant. Can work but it takes about 3-5 hours to get to 1X10^11 accuracy. Still observing various strange ness shuch as diurnal shift ... Odd wwvb works at least for me most stable in the day. I seem to remember night was supposed to be better. The signal is much stronger at night. So I guess its a play but sure not as easy as gud ole LORAN C has been. On Fri, Nov 13, 2009 at 12:48 PM, Brian Kirby <kilodelta4foxmike@gmail.com>wrote: > You will need a receiver to compare your references to. It appears that > LORAN will be shut off, so that leaves two services available, either WWV 60 > Khz or GPS. I do not use WWV any more, I can tell you about GPS. > > To compare against GPS you will need a timing receiver, there are several > available. A lot of us got Motorola Oncore VPs, UTs, or M12+, The Rockwell > Jupiter is one and there are several more. They provide a 1 PPS signal that > is locked to the on board standards on the GPS satellite. You put this > signal in one input of a time interval counter. You use a 1 PPS divider on > your local reference and put its signal in the other input of the time > interval counter. You can record continuous or take daily 24 hour readings > and derive your drift rates. > > GPS corrections are published at NIST; > http://tf.nist.gov/service/gpstrace.htm > > You can also compare against a GPS disciplined oscillator. In the long > term it should be dead on, you will have to have it characterized for the > short term. The HP Z3801A was on the surplus market several years back, its > probably one of the best. The Trimble Thunderbolts were available to the > group a while back. > Brian KD4FM > > > Glenn Little WB4UIV wrote: > >> While I was in the US Navy we had two Cesium standards for the navigation >> center on SSBN submarines. >> While in port, we would track LORAN C and compute the drift rate of the >> two cesium standards. >> Is there a service, that has drift rates published, that I can compare my >> standards to, so that I can determine the standard drift rate. >> I do not remember the drift rates that we determined on the submarine, >> that was a few years ago, but, I seem to remember that the rate was in the >> low nanoseconds. >> If a rubidium standard drifts in one direction (does it?) a drift rate >> could be calculated and, after a comparison to a known standard, with known >> drift rate, a very accurate standard could be had for the lab. >> >> What would I expect the drift rate, or jitter, to be in a FRK class >> rubidium oscillator? >> >> Is the drift rate constant enough that a drift rate could be applied to a >> rubidium oscillator to determine it's real frequency at any given time. >> >> We calibrated the submarine Cesium standards every three months. >> We had to know the drift rate of our standard as well as the drift rate of >> the standard in each of the LORAN stations to be able to do the type of >> LORAN navigation that we did. >> >> I would like to be able to verify that my PTB-100 rubidium oscillator is >> on frequency. >> >> If I compare two rubidium oscillators, what would I expect the relative >> drift rate to be? >> >> Thanks >> 73 >> Glenn >> WB4UIV >> >> >> >> >> _______________________________________________ >> 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 > and follow the instructions there. >

DL

Don Latham

Fri, Nov 13, 2009 6:15 PM

The ground wave path of WWVB varies due to a very small changes in the
index of refraction (temperature and absolute humidity) over the path. It
is not much, but is measurable.
Don

paul swed

I use GPS and LORAN. Always nice to have a backup
With LORAN being shut down, have resurrected the ole wwvb rcvr and built
an
amplified loop ant.
Can work but it takes about 3-5 hours to get to 1X10^11 accuracy. Still
observing various strange ness shuch as diurnal shift ...
Odd wwvb works at least for me most stable in the day. I seem to remember
night was supposed to be better.
The signal is much stronger at night.
So I guess its a play but sure not as easy as gud ole LORAN C has been.

On Fri, Nov 13, 2009 at 12:48 PM, Brian Kirby
kilodelta4foxmike@gmail.comwrote:

You will need a receiver to compare your references to. It appears that
LORAN will be shut off, so that leaves two services available, either
WWV 60
Khz or GPS. I do not use WWV any more, I can tell you about GPS.

To compare against GPS you will need a timing receiver, there are
several
available. A lot of us got Motorola Oncore VPs, UTs, or M12+, The
Rockwell
Jupiter is one and there are several more. They provide a 1 PPS signal
that
is locked to the on board standards on the GPS satellite. You put this
signal in one input of a time interval counter. You use a 1 PPS divider
on
your local reference and put its signal in the other input of the time
interval counter. You can record continuous or take daily 24 hour
readings
and derive your drift rates.

GPS corrections are published at NIST;
http://tf.nist.gov/service/gpstrace.htm

You can also compare against a GPS disciplined oscillator. In the long
term it should be dead on, you will have to have it characterized for
the
short term. The HP Z3801A was on the surplus market several years back,
its
probably one of the best. The Trimble Thunderbolts were available to
the
group a while back.
Brian KD4FM

Glenn Little WB4UIV wrote:

While I was in the US Navy we had two Cesium standards for the
navigation
center on SSBN submarines.
While in port, we would track LORAN C and compute the drift rate of the
two cesium standards.
Is there a service, that has drift rates published, that I can compare
my
standards to, so that I can determine the standard drift rate.
I do not remember the drift rates that we determined on the submarine,
that was a few years ago, but, I seem to remember that the rate was in
the
low nanoseconds.
If a rubidium standard drifts in one direction (does it?) a drift rate
could be calculated and, after a comparison to a known standard, with
known
drift rate, a very accurate standard could be had for the lab.

What would I expect the drift rate, or jitter, to be in a FRK class
rubidium oscillator?

Is the drift rate constant enough that a drift rate could be applied to
a
rubidium oscillator to determine it's real frequency at any given time.

We calibrated the submarine Cesium standards every three months.
We had to know the drift rate of our standard as well as the drift rate
of
the standard in each of the LORAN stations to be able to do the type of
LORAN navigation that we did.

I would like to be able to verify that my PTB-100 rubidium oscillator
is
on frequency.

If I compare two rubidium oscillators, what would I expect the relative
drift rate to be?

Thanks
73
Glenn
WB4UIV

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.

--
Dr. Don Latham AJ7LL
Six Mile Systems LLP
17850 Six Mile Road
POB 134
Huson, MT, 59846
VOX 406-626-4304
www.lightningforensics.com
www.sixmilesystems.com

The ground wave path of WWVB varies due to a very small changes in the index of refraction (temperature and absolute humidity) over the path. It is not much, but is measurable. Don paul swed > I use GPS and LORAN. Always nice to have a backup > With LORAN being shut down, have resurrected the ole wwvb rcvr and built > an > amplified loop ant. > Can work but it takes about 3-5 hours to get to 1X10^11 accuracy. Still > observing various strange ness shuch as diurnal shift ... > Odd wwvb works at least for me most stable in the day. I seem to remember > night was supposed to be better. > The signal is much stronger at night. > So I guess its a play but sure not as easy as gud ole LORAN C has been. > > On Fri, Nov 13, 2009 at 12:48 PM, Brian Kirby > <kilodelta4foxmike@gmail.com>wrote: > >> You will need a receiver to compare your references to. It appears that >> LORAN will be shut off, so that leaves two services available, either >> WWV 60 >> Khz or GPS. I do not use WWV any more, I can tell you about GPS. >> >> To compare against GPS you will need a timing receiver, there are >> several >> available. A lot of us got Motorola Oncore VPs, UTs, or M12+, The >> Rockwell >> Jupiter is one and there are several more. They provide a 1 PPS signal >> that >> is locked to the on board standards on the GPS satellite. You put this >> signal in one input of a time interval counter. You use a 1 PPS divider >> on >> your local reference and put its signal in the other input of the time >> interval counter. You can record continuous or take daily 24 hour >> readings >> and derive your drift rates. >> >> GPS corrections are published at NIST; >> http://tf.nist.gov/service/gpstrace.htm >> >> You can also compare against a GPS disciplined oscillator. In the long >> term it should be dead on, you will have to have it characterized for >> the >> short term. The HP Z3801A was on the surplus market several years back, >> its >> probably one of the best. The Trimble Thunderbolts were available to >> the >> group a while back. >> Brian KD4FM >> >> >> Glenn Little WB4UIV wrote: >> >>> While I was in the US Navy we had two Cesium standards for the >>> navigation >>> center on SSBN submarines. >>> While in port, we would track LORAN C and compute the drift rate of the >>> two cesium standards. >>> Is there a service, that has drift rates published, that I can compare >>> my >>> standards to, so that I can determine the standard drift rate. >>> I do not remember the drift rates that we determined on the submarine, >>> that was a few years ago, but, I seem to remember that the rate was in >>> the >>> low nanoseconds. >>> If a rubidium standard drifts in one direction (does it?) a drift rate >>> could be calculated and, after a comparison to a known standard, with >>> known >>> drift rate, a very accurate standard could be had for the lab. >>> >>> What would I expect the drift rate, or jitter, to be in a FRK class >>> rubidium oscillator? >>> >>> Is the drift rate constant enough that a drift rate could be applied to >>> a >>> rubidium oscillator to determine it's real frequency at any given time. >>> >>> We calibrated the submarine Cesium standards every three months. >>> We had to know the drift rate of our standard as well as the drift rate >>> of >>> the standard in each of the LORAN stations to be able to do the type of >>> LORAN navigation that we did. >>> >>> I would like to be able to verify that my PTB-100 rubidium oscillator >>> is >>> on frequency. >>> >>> If I compare two rubidium oscillators, what would I expect the relative >>> drift rate to be? >>> >>> Thanks >>> 73 >>> Glenn >>> WB4UIV >>> >>> >>> >>> >>> _______________________________________________ >>> 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 >> 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 > and follow the instructions there. > -- Dr. Don Latham AJ7LL Six Mile Systems LLP 17850 Six Mile Road POB 134 Huson, MT, 59846 VOX 406-626-4304 www.lightningforensics.com www.sixmilesystems.com

KP

Kasper Pedersen

Fri, Nov 13, 2009 6:32 PM

On 11/13/2009 07:15 PM, Don Latham wrote:

The ground wave path of WWVB varies due to a very small changes in the
index of refraction (temperature and absolute humidity) over the path. It
is not much, but is measurable.
Don

My own nuttiness started with that, and the innocent question "How much?
What does it take to measure it? What do I need to build?"

http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1)

I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is
quite large, when I started out that number seemed a lot smaller.

/Kasper Pedersen

On 11/13/2009 07:15 PM, Don Latham wrote: > The ground wave path of WWVB varies due to a very small changes in the > index of refraction (temperature and absolute humidity) over the path. It > is not much, but is measurable. > Don > My own nuttiness started with that, and the innocent question "How much? What does it take to measure it? What do I need to build?" http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1) I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is quite large, when I started out that number seemed a lot smaller. /Kasper Pedersen

DL

Don Latham

Fri, Nov 13, 2009 10:01 PM

Hi All: I've copied my paper "Diurnal frequency variation and refractive
index" from Nature Physical Sciences, Vol. 234, 51, pp. 157-158, Dec. 20,
1971. There are two TIFF files (I tried like heck to get them in one file,
and failed miserably, cannot understand my image software worth a #$%^. The
way to calculate the refractive index of moist air is given. I don't know
how to post these images to the list, so help please. There was no reason to
pursue the idea at the time, so maybe with the extensive network of the
time-nuts some sense can be made of the idea. Dunno.
Don Latham

----- Original Message -----
From: "Kasper Pedersen" time-nuts@kasperkp.dk
To: time-nuts@febo.com
Sent: Friday, November 13, 2009 11:32 AM
Subject: Re: [time-nuts] Reference oscillator accuracy

On 11/13/2009 07:15 PM, Don Latham wrote:

The ground wave path of WWVB varies due to a very small changes in the
index of refraction (temperature and absolute humidity) over the path. It
is not much, but is measurable.
Don

My own nuttiness started with that, and the innocent question "How much?
What does it take to measure it? What do I need to build?"

http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1)

I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is
quite large, when I started out that number seemed a lot smaller.

/Kasper Pedersen

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.

Hi All: I've copied my paper "Diurnal frequency variation and refractive index" from Nature Physical Sciences, Vol. 234, 51, pp. 157-158, Dec. 20, 1971. There are two TIFF files (I tried like heck to get them in one file, and failed miserably, cannot understand my image software worth a #$%^. The way to calculate the refractive index of moist air is given. I don't know how to post these images to the list, so help please. There was no reason to pursue the idea at the time, so maybe with the extensive network of the time-nuts some sense can be made of the idea. Dunno. Don Latham ----- Original Message ----- From: "Kasper Pedersen" <time-nuts@kasperkp.dk> To: <time-nuts@febo.com> Sent: Friday, November 13, 2009 11:32 AM Subject: Re: [time-nuts] Reference oscillator accuracy > On 11/13/2009 07:15 PM, Don Latham wrote: >> The ground wave path of WWVB varies due to a very small changes in the >> index of refraction (temperature and absolute humidity) over the path. It >> is not much, but is measurable. >> Don >> > > My own nuttiness started with that, and the innocent question "How much? > What does it take to measure it? What do I need to build?" > > http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1) > > I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is > quite large, when I started out that number seemed a lot smaller. > > /Kasper Pedersen > > _______________________________________________ > 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.

DJ

Didier Juges

Fri, Nov 13, 2009 10:51 PM

Don, you are welcome to upload your pictures (and paper) to my web site, where people normally upload manuals.

Didier KO4BB

http://www.ko4bb.com/cgi-bin/manuals.pl

------------------------ Sent from my BlackBerry Wireless thingy while I do other things...

-----Original Message-----
From: "Don Latham" djl@montana.com
Date: Fri, 13 Nov 2009 15:01:47
To: Discussion of precise time and frequency measurementtime-nuts@febo.com
Subject: Re: [time-nuts] Reference oscillator accuracy

Hi All: I've copied my paper "Diurnal frequency variation and refractive
index" from Nature Physical Sciences, Vol. 234, 51, pp. 157-158, Dec. 20,
1971. There are two TIFF files (I tried like heck to get them in one file,
and failed miserably, cannot understand my image software worth a #$%^. The
way to calculate the refractive index of moist air is given. I don't know
how to post these images to the list, so help please. There was no reason to
pursue the idea at the time, so maybe with the extensive network of the
time-nuts some sense can be made of the idea. Dunno.
Don Latham

----- Original Message -----
From: "Kasper Pedersen" time-nuts@kasperkp.dk
To: time-nuts@febo.com
Sent: Friday, November 13, 2009 11:32 AM
Subject: Re: [time-nuts] Reference oscillator accuracy

On 11/13/2009 07:15 PM, Don Latham wrote:

The ground wave path of WWVB varies due to a very small changes in the
index of refraction (temperature and absolute humidity) over the path. It
is not much, but is measurable.
Don

My own nuttiness started with that, and the innocent question "How much?
What does it take to measure it? What do I need to build?"

http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1)

I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is
quite large, when I started out that number seemed a lot smaller.

/Kasper Pedersen

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
and follow the instructions there.

Don, you are welcome to upload your pictures (and paper) to my web site, where people normally upload manuals. Didier KO4BB http://www.ko4bb.com/cgi-bin/manuals.pl ------------------------ Sent from my BlackBerry Wireless thingy while I do other things... -----Original Message----- From: "Don Latham" <djl@montana.com> Date: Fri, 13 Nov 2009 15:01:47 To: Discussion of precise time and frequency measurement<time-nuts@febo.com> Subject: Re: [time-nuts] Reference oscillator accuracy Hi All: I've copied my paper "Diurnal frequency variation and refractive index" from Nature Physical Sciences, Vol. 234, 51, pp. 157-158, Dec. 20, 1971. There are two TIFF files (I tried like heck to get them in one file, and failed miserably, cannot understand my image software worth a #$%^. The way to calculate the refractive index of moist air is given. I don't know how to post these images to the list, so help please. There was no reason to pursue the idea at the time, so maybe with the extensive network of the time-nuts some sense can be made of the idea. Dunno. Don Latham ----- Original Message ----- From: "Kasper Pedersen" <time-nuts@kasperkp.dk> To: <time-nuts@febo.com> Sent: Friday, November 13, 2009 11:32 AM Subject: Re: [time-nuts] Reference oscillator accuracy > On 11/13/2009 07:15 PM, Don Latham wrote: >> The ground wave path of WWVB varies due to a very small changes in the >> index of refraction (temperature and absolute humidity) over the path. It >> is not much, but is measurable. >> Don >> > > My own nuttiness started with that, and the innocent question "How much? > What does it take to measure it? What do I need to build?" > > http://n1.taur.dk/dcf/ (raw data and plots, time is UTC+1) > > I am no more than 6-700 km north of DCF77, and get ~5us p-p. Now that is > quite large, when I started out that number seemed a lot smaller. > > /Kasper Pedersen > > _______________________________________________ > 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 and follow the instructions there.

DI

David I. Emery

Sat, Nov 14, 2009 2:27 AM

On Fri, Nov 13, 2009 at 09:51:11AM -0800, J. Forster wrote:

WWVB not WWV.

IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that LORAN
is being shut down.

I have emailed my brother in law who is a rear admiral (I think

now called a vice admiral) and currently CFO of the USCG (and as a note
re your alma mater a MIT Sloan grad) and rather loudly said so myself.
He most likely was part of the group that made the decision... I intend
to ask him why they did it when I next see him.

--
Dave Emery N1PRE/AE, die@dieconsulting.com DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole - in
celebration of what could have been, but wasn't and is not to be now either."

On Fri, Nov 13, 2009 at 09:51:11AM -0800, J. Forster wrote: > WWVB not WWV. > > IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that LORAN > is being shut down. I have emailed my brother in law who is a rear admiral (I think now called a vice admiral) and currently CFO of the USCG (and as a note re your alma mater a MIT Sloan grad) and rather loudly said so myself. He most likely was part of the group that made the decision... I intend to ask him why they did it when I next see him. -- Dave Emery N1PRE/AE, die@dieconsulting.com DIE Consulting, Weston, Mass 02493 "An empty zombie mind with a forlorn barely readable weatherbeaten 'For Rent' sign still vainly flapping outside on the weed encrusted pole - in celebration of what could have been, but wasn't and is not to be now either."

JF

J. Forster

Sat, Nov 14, 2009 3:01 AM

I asked a close friend and fellow engineering alum who was deeply involved
in GPS and he thinks closing down LORAN is utterly idiotic.

IMO, there is something purely political, rather than technical, about
this decision.

Perhaps the GPS "stakeholders" don't want to admit just how vulnerable GPS
is to jamming (and hence a backup is not needed), just as software vendors
don't want to admit security holes or banks want to admit that millions
are stolen through computer fraud.

FWIW,
-John

BTW, Sloan is a school of Management, NOT Engineering. There is a VERY big
difference.

===================

On Fri, Nov 13, 2009 at 09:51:11AM -0800, J. Forster wrote:

WWVB not WWV.

IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that
LORAN
is being shut down.

I have emailed my brother in law who is a rear admiral (I think

now called a vice admiral) and currently CFO of the USCG (and as a note
re your alma mater a MIT Sloan grad) and rather loudly said so myself.
He most likely was part of the group that made the decision... I intend
to ask him why they did it when I next see him.

--
Dave Emery N1PRE/AE, die@dieconsulting.com DIE Consulting, Weston, Mass
02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
'For Rent' sign still vainly flapping outside on the weed encrusted pole -
in
celebration of what could have been, but wasn't and is not to be now
either."

I asked a close friend and fellow engineering alum who was deeply involved in GPS and he thinks closing down LORAN is utterly idiotic. IMO, there is something purely political, rather than technical, about this decision. Perhaps the GPS "stakeholders" don't want to admit just how vulnerable GPS is to jamming (and hence a backup is not needed), just as software vendors don't want to admit security holes or banks want to admit that millions are stolen through computer fraud. FWIW, -John BTW, Sloan is a school of Management, NOT Engineering. There is a VERY big difference. =================== > On Fri, Nov 13, 2009 at 09:51:11AM -0800, J. Forster wrote: >> WWVB not WWV. >> >> IMO, WWVB is MUCH fussier than LORAN. It's just utter stupidity that >> LORAN >> is being shut down. > > I have emailed my brother in law who is a rear admiral (I think > now called a vice admiral) and currently CFO of the USCG (and as a note > re your alma mater a MIT Sloan grad) and rather loudly said so myself. > He most likely was part of the group that made the decision... I intend > to ask him why they did it when I next see him. > > > -- > Dave Emery N1PRE/AE, die@dieconsulting.com DIE Consulting, Weston, Mass > 02493 > "An empty zombie mind with a forlorn barely readable weatherbeaten > 'For Rent' sign still vainly flapping outside on the weed encrusted pole - > in > celebration of what could have been, but wasn't and is not to be now > either." > >

time-nuts@lists.febo.com

Reference oscillator accuracy