[time-nuts] Next Generation Time/Frequency Standards May Require Provisions Preventing Vertical Displacement

[Magnus Danielson]

On 09/29/2010 06:56 PM, Jeffrey Okamitsu wrote:
> Actually, as I think about this, it will be impossible to "calibrate" another
> device unless one knows the vertical displacement between the standard and the
> DUT AND a suitably adequate (read: easy to use) algorithm for accounting for the
> effect of gravity can be developed.

You can compare two standards by levelling their gravitational centers 
(similar to phase centers of GPS antennas) to the same level or within 
same level to what degree they are comparable too.

Wither they need to be within 1 mm, 100 mm, 10 m or 1 km depends on the 
quality of the oscillators.

Cheers,
Magnus