[time-nuts] Comparing PPS from 2 GPS units

SAIDJACK at aol.com SAIDJACK at aol.com
Sat Dec 15 04:07:03 UTC 2012

Hi Tom,
but they could have achieved the same exact result by using scientific  
notation such as:
to note the higher internal resolution in the later case.
I realize that one can easily parse these raw outputs, if one can  write 
python or C etc quickly, but I always find myself doing "search and  replace: 
'* u' with '0E-06" in Word etc..
Also I don't happen to have a 1us long and accurate delay line, and I have  
to measure two pulses very close to each other, so I have no real choice in 
the  matter at this time. The jitter can be up to +/-1us, so I need that 
1us  delay to keep the values positive.
It would be good if the programmers would have added options to select the  
output format, and how to count time intervals close to zero when going  
negative. This should have been very easy to add in the counter's  software.
Maybe there is a Windows executable out there that can parse raw 53132A  
counter log files, recognize what the data is, and turn them into  proper 
scientific notation as well as handling the 0.999,999,999  second issue, that 
can then be directly read by programs such as  Excel, Plotter, etc?
Time-Nuts, anyone willing to write this for the benefit of all?
In a message dated 12/13/2012 22:55:42 Pacific Standard Time,  
tvb at LeapSecond.com writes:

>  Absolutely horrible to parse, these guys should have heard of scientific 
> notation. Not sure who programmed that unit, or if there is a  firmware  
> upgrade that gives proper numbers.

They are  more proper than you think. Do you remember one of the first 
lessons in  high-school science class: scientific measurements have both value 
and  precision. Thus 2.3 is not the same as 2.30 which is not the same as 
2.300.  Precision is important. When the 53132A adds "*" it conveys to the user 
that  precision is  missing.


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