On 5/5/13 1:48 AM, Magnus Danielson wrote:
On 05/05/2013 10:05 AM, Attila Kinali wrote:
On Sat, 4 May 2013 12:36:20 -0700
Tom Van Baak (lab)t...@leapsecond.com wrote:
Rule of thumb: quartz is best short term, Rb or H-maser mid-term,
and Cs by far the best long-term.
Ah.. so it's a
Hi
Mercury was tried very early on as a vapor standard. They had some significant
problems with it in the 1950's. It's not surprising that after 60 years
somebody might want to take another swing at it.
Bob
On May 5, 2013, at 9:59 AM, Jim Lux jim...@earthlink.net wrote:
On 5/5/13 1:48 AM,
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
When people say rubidium is inferior to cesium, they
On 5/5/13 8:42 AM, Richard (Rick) Karlquist wrote:
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
When
Hi Jim,
On 05/05/2013 03:59 PM, Jim Lux wrote:
On 5/5/13 1:48 AM, Magnus Danielson wrote:
The above is a summary of things collected from a variety of sources,
but I think this coarse walk-through of issues gives some insight as to
what issues pops up where and the milage vary a lot within
On 05/05/2013 06:50 PM, Jim Lux wrote:
On 5/5/13 8:42 AM, Richard (Rick) Karlquist wrote:
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important to understand that
the architecture is the key
On 5/5/13 10:05 AM, Magnus Danielson wrote:
On 05/05/2013 06:50 PM, Jim Lux wrote:
On 5/5/13 8:42 AM, Richard (Rick) Karlquist wrote:
At HP in the 1990's, Len Cutler's group built some experimental
mercury ion standards for USNO (IIRC). They were of the
trapped ion type. BTW, it is important
On 5/5/13 10:01 AM, Magnus Danielson wrote:
Hi Jim,
On 05/05/2013 03:59 PM, Jim Lux wrote:
On 5/5/13 1:48 AM, Magnus Danielson wrote:
The above is a summary of things collected from a variety of sources,
but I think this coarse walk-through of issues gives some insight as to
what issues pops
In message 51867df4.4010...@karlquist.com, Richard (Rick) Karlquist writes:
BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
Well, somewhat.
Some flavours of atoms don't work with some architectures, so for
most of the stuff in reach for us,
Hi Jim,
On 05/05/2013 07:33 PM, Jim Lux wrote:
On 5/5/13 10:05 AM, Magnus Danielson wrote:
They have been targeting this goal for a very long time. Several
interesting papers is to be found at PTTI, NIST etc.
Yeah.. some years (6 or 7?) ago, John Prestage had a prototype of the
physics
On Sun, 05 May 2013 18:29:53 +
Poul-Henning Kamp p...@phk.freebsd.dk wrote:
In message 51867df4.4010...@karlquist.com, Richard (Rick) Karlquist
writes:
BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
Well, somewhat.
Some
In message 20130505205257.8497f166abb1e49186953...@kinali.ch, Attila Kinali w
rites:
I also have never seen a H gas cell standard, probably for the same reason
of needing UV light.
Hydrogen is very hard to contain.
The way you *filter* hydrogen is to press it through a palladium film,
and that
Hi Poul-Henning,
On 05/05/2013 08:29 PM, Poul-Henning Kamp wrote:
In message51867df4.4010...@karlquist.com, Richard (Rick) Karlquist writes:
BTW, it is important to understand that
the architecture is the key factor, not the flavor of atom.
Well, somewhat.
Some flavours of atoms don't work
On 05/05/2013 09:28 PM, Poul-Henning Kamp wrote:
In message20130505205257.8497f166abb1e49186953...@kinali.ch, Attila Kinali w
rites:
I also have never seen a H gas cell standard, probably for the same reason
of needing UV light.
Hydrogen is very hard to contain.
The way you *filter*
On 5/5/13 11:45 AM, Magnus Danielson wrote:
Hi Jim,
On 05/05/2013 07:33 PM, Jim Lux wrote:
On 5/5/13 10:05 AM, Magnus Danielson wrote:
They have been targeting this goal for a very long time. Several
interesting papers is to be found at PTTI, NIST etc.
Yeah.. some years (6 or 7?) ago, John
On 05/05/2013 11:14 PM, Jim Lux wrote:
On 5/5/13 11:45 AM, Magnus Danielson wrote:
Hi Jim,
On 05/05/2013 07:33 PM, Jim Lux wrote:
On 5/5/13 10:05 AM, Magnus Danielson wrote:
They have been targeting this goal for a very long time. Several
interesting papers is to be found at PTTI, NIST etc.
the
development.
This link has the basics: http://tf.nist.gov/general/pdf/1957.pdf. I want two.
Thomas Knox
1-303-554-0307
Date: Sun, 5 May 2013 06:59:12 -0700
From: jim...@earthlink.net
To: time-nuts@febo.com
Subject: [time-nuts] vs Hg ion? Re: GPS clock stabilitiy, Rb vs Cs
On 5/5/13 1:48 AM
Hi Tom,
On 05/05/2013 11:33 PM, Tom Knox wrote:
The idea of a Mercury Ion clocks started about 2000 and from about 2005 until
recently has held the title of worlds most accurate clock.
Approx 1 sec per 1.6 billion years the last I heard. At the heart is a single
trapped mercury atom. Jim
On 5/5/13 2:49 PM, Magnus Danielson wrote:
I have all the Hg-199 and Hg-202 I need for a few clocks, but in it's
natural mixture. Don't feel like building a separation facility...
Use the quadrupole system you're using as a trap as a mass-spec to do
the separation.
Hi
There were a number of trapped ion papers back in the 70's and 80's. The NIST
effort to transition from Cs to an ion standard was well underway by the mid
1980's.
Bob
On May 5, 2013, at 5:49 PM, Magnus Danielson mag...@rubidium.dyndns.org wrote:
Hi Tom,
On 05/05/2013 11:33 PM, Tom
that lead the
development.
This link has the basics: http://tf.nist.gov/general/pdf/1957.pdf. I want
two.
Thomas Knox
1-303-554-0307
Date: Sun, 5 May 2013 06:59:12 -0700
From: jim...@earthlink.net
To: time-nuts@febo.com
Subject: [time-nuts] vs Hg ion? Re: GPS clock stabilitiy
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