Re: Reinventing a Synchronome
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Bepi et al,
The clock I referred to was (and still is, although I no longer have it) a Russian "Etalon" free pendulum clock. It is based on (and is a copy of) the Shortt-Synchronome free pendulum clock, of which about 30 copies were made. My clock had been installed, along with another mounted at right angles to one another, in an establishment in Novosibirsk where it was used primarily for gravity measurement. It is well known that variations in gravity can be measured by precision pendulums, so my observation of the phases of the Moon was to be expected.
It will be very interesting to see if your clock can achieve the degree of stability and accuracy to repeat this. It should, however, be noted that the Etalon and Shortt clocks (and others) are housed in a sealed and evacuated chamber to remove any effects of barometric pressure variations.
I confess that I don't understand all the electronic wizardry that you are employing, but it's all aimed at the same goal!
Keep up the good work!
From: Bepi <pepicima@...>
To: synchronome1 <firstname.lastname@example.org>
Sent: Thu, 23 Jan 2020 18:10
Subject: Re: [synchronomeelectricclock] Reinventing a Synchronome
As far as Ian and Johannes suggestions i find them exceptionally interesting. I would happy to participate (discuss) in what seems to me, for what I know now, a promising new experiment: a sort of long timebase intensity correlation interferometry between two, or more, synchronomes.
A mouthful of big words but in reality something very simple: cross correlating the fluctuations of the period measurements of two clocks, possibly located where the main natural causes for fluctuations are uncorrelated. Europe and oceania for anything weather and seismic related would be good choices, I can't think of more uncorrelated weather on earth.
The two clocks will be slightly detuned, it doesn't matter, and one could use just the periods away from impulsing, the free falling ones, most of them, to avoid any escapement error noise and employ all kind of differently impulsed synchronomes. In practice one would only make a quartz clock precision recording of individual periods for times very long compared to the tidal period, months for example, gaining square root of measuring-time / tidal-period in sensitivity if the rest is uncorrelated.
The computational part is readily available in all kinds of math software, not an issue.
The result with respect to tides would be an original and independent measurement of the relative longitude of the two clocks through a measurement of the cross-phase of the correlation. It would never compete with GPS but, if it works, very rewarding.
About Johannes suggestion: does any body think that tides would be the only correlated signal one would find? after years of measurements? turbulence of earth core movements is a good candidate. Ever been measured by gravitometers?Bepi
First thing to do would be a simulation to see if it works in theory, very encouraging that Ian was already seeing the phases of the moon...