Re: [time-nuts] Einstein Special on PBS

The mountain thing has been done. Someone needs to take their clock to the bottom of the deepest mine (2.4 miles). ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and

[time-nuts] Einstein Special on PBS

Another thing to consider is the gravity anomaly caused by that hunk of granite beneath your clock (or above it in a mine). Hmmm, what is the clock shift at the top of Mt Everest that is due to the mountain and not the altitude?

Re: [time-nuts] Einstein Special on PBS

Hal, Right. The orbits are nominally circular -- but not exactly. The set of orbital parameters cover these details. A quick google search suggests the eccentricity for GPS is around 0.01. Still, that's enough to cause +/- 23 ns of accumulated phase error per orbit. I'm pretty sure the

Re: [time-nuts] Einstein Special on PBS

Mark, Gravity mapping is a highly developed technology. Not just Everest, but the whole planet: http://op.gfz-potsdam.de/grace/results/grav/g001_eigen-grace01s.html http://www.geology.sdsu.edu/kmlgeology/kmz/gravity_grace/grace.jpg Or use this search and enjoy every image. It's just stunning:

Re: [time-nuts] Einstein Special on PBS

It's not exactly a rigorous explanation, but I think it's a good memory aid. Once you realize that c is a 4D constant rather than a scalar speed, you can work out for yourself which way clock measurements are skewed from various points of view. -- john, KE5FX > -Original Message- >

Re: [time-nuts] Einstein Special on PBS

On 11/29/15 12:13 PM, Mark Sims wrote: Another thing to consider is the gravity anomaly caused by that hunk of granite beneath your clock (or above it in a mine). Hmmm, what is the clock shift at the top of Mt Everest that is due to the mountain and not the altitude?

Re: [time-nuts] Einstein Special on PBS

Hi > On Nov 29, 2015, at 3:15 PM, Hal Murray wrote: > > > kb...@n1k.org said: >> If you dig into the gravity stuff, they get into questions like “do we put >> in a term for the gravitational effects of Pluto? Yes, there are Gravity >> Nuts…. > > Things like that

Re: [time-nuts] Einstein Special on PBS

Hi > On Nov 29, 2015, at 11:31 AM, Tom Van Baak wrote: > > Hal, > > Right. The orbits are nominally circular -- but not exactly. The set of > orbital parameters cover these details. A quick google search suggests the > eccentricity for GPS is around 0.01. Still, that's

Re: [time-nuts] Einstein Special on PBS

Wow. So elegantly simple explanation, thanks John! On November 27, 2015 2:54:51 PM CST, John Miles wrote: >So, here's how I finally grokked this stuff. c, the speed of light in >a vacuum, is often spoken of as a "speed limit" that nothing can ever >exceed. That's a bad way to

Re: [time-nuts] Einstein Special on PBS

The whole "t" thing was bothering me in John's explanation, so I showed it to my son the physicist. He tells me that John's explanation comes from Brian Greene's book, "The Elegant Universe"... A very popular coffee table book, aimed at the same market as those by Stephen Hawking. Greene's

Re: [time-nuts] Einstein Special on PBS

The reference was probably a bit too obscure for an international audience. :) https://www.youtube.com/watch?v=VPJqIT7a3qA -- john, KE5FX Miles Design LLC > Hi John, > > Thank you very much for this explanation, I found it very "explicative". > What I am not able to grasp is the sense of the

[time-nuts] Einstein Special on PBS

Yep, been there, done that... I own a Worden gravity meter. Gravity mapping is a highly developed technology. Not just Everest, but the whole planet: ___ time-nuts mailing list --

Re: [time-nuts] Einstein Special on PBS

kb...@n1k.org said: > If you dig into the gravity stuff, they get into questions like “do we put > in a term for the gravitational effects of Pluto? Yes, there are Gravity > Nuts…. Things like that have a significant influence on planetary orbits. Do they have a measurable influence on

Re: [time-nuts] Einstein Special on PBS

t...@leapsecond.com said: > I'm not sure I understand your elevation question. Are you talking about > elevation as in mountain vs. sea level altitude? Or elevation as in > satellite Az/El? I was thinking of the elevation of the receiver as in mountain vs sea level. I think the question I was

Re: [time-nuts] Einstein Special on PBS

Hi John, Thank you very much for this explanation, I found it very "explicative". What I am not able to grasp is the sense of the phrase " That second part was what really baked peoples' noodles". I think that is some colloquial but not being English my native language I can't figure out its

Re: [time-nuts] Einstein Special on PBS

Chris, A few years after my Mt Rainier trip I looked into doing the same experiment down a mine. But besides having mountains Seattle also has the Pacific ocean so there are any number of commercial and research deep sea operations around here. I thought it would fun to put a few 5071A and

Re: [time-nuts] Need tiny 5MHz 10x amplifier

Am 29.11.2015 um 01:35 schrieb Poul-Henning Kamp: I need to convert a 5MHz 0.2Vpp AC coupled sine signal to a 3.3V CMOS compatible logic signal. The "default" comparator based circuit either requires a negative supply or 4 resitors for biasing the input and setting the zero level. (The

Re: [time-nuts] Einstein Special on PBS

hol...@hotmail.com said: > The GPS spec implies the satellites have a fixed frequency offset to > compensate for relativistic effects. But do they actually dynamically and/ > or individually adjust the frequency to adjust for orbit variations and > eccentricities?

Re: [time-nuts] Need tiny 5MHz 10x amplifier

I wrote: The LT1720** works on a 3.3v single supply, and has internal hysteresis. Just ground one input, ground the other through a resistor, and attach your AC-coupled signal (best if you can use equal resistors to ground on the two inputs, but if the signal termination is 50 ohms the

Re: [time-nuts] Need tiny 5MHz 10x amplifier

>From the data sheet it looks like a megohm range bias resistor is needed (X1 >to X2) as well as the blocking / coupling cap. Robert LaJeunesse > Sent: Sunday, November 29, 2015 at 5:15 PM > From: "Cash Olsen" > To: time-nuts@febo.com > Subject: Re: [time-nuts] Need

Re: [time-nuts] Need tiny 5MHz 10x amplifier

How about a part like a: SN74LVC1GX04DCKR IC CRYSTAL OSC DRIVER SC70-6 With a DC blocking capacitor the part should be self-biasing and give logic outputs. -- S. Cash Olsen KD5SSJ ARRL Technical Specialist On Sat, Nov 28, 2015 at 7:35 PM, Poul-Henning Kamp wrote: > I need

[time-nuts] First results with the ACAM GP22 chip

Hello Time-Nuts, As threatened in earlier postings I can now show some results gathered with the ACAM GP22 TDC chip and evaluation board. Admittedly this is only from its "range 1" at the moment. The setup was suitably simple to match my almost non-existent level of expertise and available