[time-nuts] GPS jump

[Jim Lux]

On 10/11/14, 8:08 AM, Bob Camp wrote:
> Hi
>
> To the extent that anything *is* locked, it’s been done for a lot longer than the 1980’s. Long before common view GPS, Loran-C observations (and corrections via clock trips) were used. You can look at it as a PLL, just a *very* fancy one with *very* long time constants.
>
> Bob
>
>

It also depends on whether you need "lock in real time" or "lock in post 
processing".

VLBI is a good example of the latter, and was done in the early 70s to 
determine the position of the moon rover, for example.