[aprssig] OpenAPRS for iPhone 2.3.1 Released

Bob Bruninga bruninga at usna.edu
Mon Jan 24 12:26:32 EST 2011

>> Sending the original position is not a problem 
>> for DRing as long as the original TIME is also sent.  

> That always depends on who's implementation 
> of DR you're talking about and whether or not the 
> object originator includes a real starting
> timestamp or 111111z and/or if the times between 
> the various machines are synchronized closely 
> enough to avoid inaccuracies in the DR
> calculations, especially for fast-moving objects.

Yes, all these must be considered. I agree that you have a real problem with
time zones!  Good luck.  But for the others, here are the approaches I

Things with fixed-default time stamps [111111z] are not moving and so they
are not DR'ed.  Shouldn't be a problem.

Time sync is a personal problem.  If someone's PC is not synced with real
time, then DR errors are an obvious consequence.  Solution is to correct the
PC's time.

And most importantly the display of a DR'ed position should never appear the
same as a non DR'ed station.  There must be some clear distinction and I
claim, there must be a DR line back to the original position so that there
is no confusion whatsoever by any viewer that the DR position is not so much
an appearance of a "position" but of a passage of TIME since the last

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