[time-nuts] Precise manual survey (was Common sky pps...)

Peter Vince pvince at theiet.org
Tue Jan 6 11:22:52 UTC 2009


Said wrote:

>When we say units typically have 25ns unit-to-unit variation on the 1PPS on  
>un-calibrated units, then I believe most of this is caused by the auto-survey  
>position errors of the GPS receiver. One could get much better performance by 
> manually entering the exact position-hold position of the antenna, and then  
>calibrating for antenna cable delay (in 1ns steps).

A naive question, if I may: how do I go about doing a precise manual position survey? Is it simply a case of letting the unit self 
survey, then manually entering different co-ordinates (say +/- 10 metres) in each of the three directions in turn, watch the 
signal output, and try to tune for minimum wobble?

Thanks,  Peter





More information about the time-nuts mailing list