Thread: Zac scare
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[email protected] tsmwebb@gmail.com is offline
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First recorded activity by BoatBanter: Sep 2006
Posts: 859
Default Zac scare

On Sep 8, 12:02*pm, "Roger Long" wrote:
Yes, SPOT uses its GPS for position and then sends the position over the
Iridium network. *I'm not familiar with the Sat phones and it never crossed
my mind that they would provide position information. *...


Just for the more tech minded here's what the wiki says about Iridium
positions:

Tracking transceiver units

Without an extra GNSS receiver tracking is difficult, but not
impossible as the position of a mobile unit can be determined using a
Doppler shift calculation from the satellite. These readings however
can be inaccurate with errors in the tens of kilometers. [12]Even
without using Doppler shifts a rough indication of a unit's position
can be found by checking the location of the spot-beam being used.

The position readings can be extracted from some transceiver units and
the 9505A handset using the -MSGEO AT command. It returns values as
the number of kilometers from the prime meridian and the equator[24]

-- Tom.