On Tue 2018-11-20T19:02:16-0500 Tom Holmes hath writ:
> So if the SI second is specified at sea level, and we know from
> Einstein and TVB's work that going up a mountain changes a clock's
> period, how would the second be affected at the center of the Earth (
> ignore thermal problems, this is a
A few years ago I did some measurements of WWV Doppler shift, measured by a 0.1
Hz resolution you get in an HP 3586C selective voltmeter. It's not quite a
phase record but does show the significant shifts that occur.
See https://www.febo.com/pages/hf_stability/
John
On Nov 20, 2018,
So if the SI second is specified at sea level, and we know from Einstein and
TVB's work that going up a mountain changes a clock's period, how would the
second be affected at the center of the Earth ( ignore thermal problems, this
is a conceptual discussion) where the net gravity vector might
Hi
Having looked at WWV with a Carrier -> BFO -> audio card approach (and a radio
locked to an Rb standard …) you have dig a bit to find a situation that is
beyond a tenth of a ppm. If you average over minutes or tens of minutes (which
is exactly what you do with WWVB) the only time you get
> That was the first time that I had seen an xy plot of WWV versus a
> stable crystal oscillator. It is even worse than I thought. I had to
> look up FRK to see that it is a rubidium standard. I talked to Jim
> Maxton the chief engineer of WWVB many times around 1995.
An xy cycle of WWV is
That was the first time that I had seen an xy plot of WWV versus a
stable crystal oscillator. It is even worse than I thought. I had to
look up FRK to see that it is a rubidium standard. I talked to Jim
Maxton the chief engineer of WWVB many times around 1995. At the time
I was in Gila Bend 80
Starting 1970 I used a modified Tracor 599H on WWVB with excellent results. It
had a mechanical counter with 100 nsec, resolution. Noisy but perfect. Yes you
have to take Ionosphere sunrise and sunset in to consideration and the hourly
shift, but being a very early riser 4AM because of Europe
