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0 pointsleggomylibro8y ago0 comments

I mean, it's not an atomic clock, but I'm comparing it to the 32.768KHz RTC crystals I use with consumer microchips. If super-precise isolated accuracy were actually important, I assume they would use a rubidium or cesium oscillator.

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grkvlt8y ago

1/3 of a second in 100 hours is basically 1ppm, or TXCO levels of accuracy, so pretty good i'd have thought, even for a submarine INS?

cocoablazing8y ago

USN ballistic missile submarines deploy the most accurate INS in the world (ESGN), and that system is used in conjunction with another advanced gyro.

grkvlt8y ago

Not sure about that. ESGN is old technology, since submarines don't need that much accuracy. For example, space probes, ballistic missiles, smart artillery shells/rockets/missiles and so on would all appear to have multiple orders of magnitude better accuracy than submarines, in the fractional ppb ranges, rather than tens of ppm. [0][1]

0. https://www.sto.nato.int/publications/STO%20Meeting%20Procee...

1. http://users.cecs.anu.edu.au/~Jonghyuk.Kim/teaching/Inertial...

GCU-Empiricist8y ago

Here is a 2 RU atomic clock on ebay for context: https://www.ebay.com/itm/Antelope-Audio-Isochrone-10M-Rubidi...

j / k navigate · click thread line to collapse

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grkvlt8y ago

1/3 of a second in 100 hours is basically 1ppm, or TXCO levels of accuracy, so pretty good i'd have thought, even for a submarine INS?

cocoablazing8y ago

USN ballistic missile submarines deploy the most accurate INS in the world (ESGN), and that system is used in conjunction with another advanced gyro.

grkvlt8y ago

0. https://www.sto.nato.int/publications/STO%20Meeting%20Procee...

1. http://users.cecs.anu.edu.au/~Jonghyuk.Kim/teaching/Inertial...

GCU-Empiricist8y ago

Here is a 2 RU atomic clock on ebay for context: https://www.ebay.com/itm/Antelope-Audio-Isochrone-10M-Rubidi...

j / k navigate · click thread line to collapse