There were a few other things happened in that time as well that you might
have missed. Have you heard of Kevin Rudd???? :-)
2009/12/28 Peter Shute <>
> So my information is 9 years out of date? Oh, well, that's not too bad for
> me.
>
> Peter Shute
>
>
> --------------------------
> Sent using BlackBerry
>
> ------------------------------
> *From*: Dave Torr
> *To*: Peter Shute
> *Cc*: ;
> *Sent*: Mon Dec 28 07:07:04 2009
> *Subject*: Re: [Birding-Aus] Re:The perfect phone for a birder?
> Selective Availability - the system that gave civilians a degraded GPS
> compared to the military - was turned off in 2000. Wikipedia (of course) has
> a pretty good article on GPS describing the various sources of error and
> what can be done to improve accuracy.
> But as you say 10m is pretty good for most birding locations - unless you
> are trying to pinpoint a specific tree in a dense forest, in which case GPS
> will probably not be getting signals anyway so will be useless!
>
> 2009/12/28 Peter Shute <>
>
>> Regarding GPS accuracy, my phone generally claims the coordinates are
>> within 10m, sometimes much lower, occasionally higher. I would imagine
>> that's easily good enough for finding most birding locations again, what
>> kind of accuracy are you talking about?
>>
>> I'm under the impression satellite signals are deliberately encoded to
>> prevent civilians getting too much better accuracy than that, for military
>> reasons, including making it hard to pinpoint the location of the actual
>> satellites in order to shoot them down. To get better accuracy (precision
>> might be a better word), I think a long succession of coordinates must be
>> averaged. This may be what the more expensive gear does.
>>
>> Not so very long ago, GPS wasn't even an option. The alternative for those
>> without access to expensive electronic distance measuring equipment was a
>> tape measure or triangulation. In my opinion, the decision by the USA to
>> release even this level of accuracy to civilians is absolutely wonderful,
>> even if it does occasionally lead you back to the wrong side of the creek.
>>
>> Peter Shute
>>
>>
>> --------------------------
>> Sent using BlackBerry
>>
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