[time-nuts] new gps sat prn30 svn64

tom jones epoch_time at yahoo.com
Wed Mar 5 14:06:23 EST 2014

Looking at my previous post today I see that I should point out something else in my parsing programings output

The last colume I labled a clk bias corrections is somewhat misleading.
numbers displayed x.xxxe-7 x.xxxe-8 are corrections.

numbers displayed as x.xxxxe-3 x.xxxxe-4 x.xxxxe-5 x.xxxx e-6 are simply numbers carried (not clk corrections) over from 

the 1st item (clk bias) after a  restart of my parser program (or new sat aquisition). last colume is current clk bias 

subtracting previous clk bias. If no previous clk data then the current clk bias (item one) is displayed in the clk 

correction colume.

I stop and start old and new loging each day around 7am. I start my parser display program many times daily till it 

reached end of file. Which could be eof for live loging (most allways) or eof for old logs.

the last colume of my parsers display is a subtraction of item one (clk bias) from the previous received item one. 

So when I start my parser on the current log. all clock corrections (last item) are exact copies of the first item.
As the parser encounters a new satellite where no previous data was recorded the last colume is duplicated from the first 


To finalize this explaination. last colume numbers x.xe-3 x.xe-4 x.xe-5 are the result of the parser not having any 

previous data for the satellite so the utc time stamp will indicate parser start time or first sat reception time.
easly seen when first and last items are nearly equal or equal.
(unintended artifact not intended but usefull)

I may have labeled the last item in a misleading way..

last item data x.xe-7 x.xe8 are clk bias corrections/updates

current parser program restart;

prn clk bias     freq drift    delta of      delta of   last    clk bias   time 
#                               2nd value     1st Value update  correction 
01 2.525953e-06 1.631754e-12   6.486673e-15  4.8961e-11 1800  3.286320e-07 1724

03 3.340867e-04 8.056584e-12   3.874245e-14  -1.5889e-10 1800 3.340513e-04 0000

11 -4.695983e-04 -6.476012e-12 1.412759e-14  -9.3290e-11 1800 -4.695533e-04 1619

^C 1.930643e-04 -8.978439e-13  -2.771871e-15 -2.6940e-11 1800 1.930712e-04 0000


18 3.055987e-04 7.472895e-13   -3.550567e-14 2.2420e-11 1800  3.055796e-04 0000
19 -4.428422e-04 4.888999e-135 1.240197e-14  -4.9387e-10 1800 -4.428375e-04 0000

21 -3.475654e-04 -8.740432e-12 -2.151404e-14 -2.5348e-10 1741 -3.475278e-04 0000
22 2.175630e-04 3.054865e-12   -1.646469e-14 9.1440e-11 1800  2.175378e-04 0000

24 -2.445189e-05 -7.379998e-13 4.726525e-15  -4.8765e-11 1747 -2.444636e-05 0000

27 -2.002264e-05 -2.966025e-13 -8.847632e-16 -8.9070e-12 1800 -2.002083e-05 0000

31 3.336526e-04 -2.108104e-12  9.688647e-15  -3.0425e-10 1800 3.336634e-04 1645
32 -4.747259e-04 5.652165e-12  2.742468e-14  1.7002e-10 1800  -3.687709e-07 1619

36 41 1782 324070000 03 05 2014
 77429 79876 000 28728 cli00 hed00
 hpe422 vpe110 ck 1829842956 dft 1832604
 cder0 dist0 derr0 hder0 sats10 hdop4

Notice identical items in first and last columes where time stamp is 0000
This means parser had to previous data to subtract from item 1 and probably no message 41 to get time from.
Also around line 13 I (ctrl C) broke out of dos program to copy and past latest data.

I find lots of usefullness leaving the last item as is. but thought I better try to explain it to everyone.

Notice not many recorded satellites yet in todays log.

Note prn30 is turned off so far today..interesting. (19:00utc) It should have been in the above example.

I have a alot of clean up programming to make this parser presentable.

Hope this helps.. Tom

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