I assumed that the PBL, would transmit something like the much more accurate GPS NMEA 0183 GLL sentence to the satellite (minute to 2 decimal places) rather than a limited accuracy compressed binary formated positional message presumably to save data bandwidth for the satellite transmission. +- 404 feet at the equator could be problematic especially for example if under the Brazilian Jungle canopy.

So does this mean that the SPOT device is actually much more accurate in its positional fixes or is it constrained by the same limitations on transmitting its GPS fix calculation due to the constrained binary message format to the satellite? I seem to remember seeing that the SPOT device doesn't have this limitation.

It seems that the constrained transmit message could easily give SAR potentially a lot more work to do or even cost lives due to the extra search time just over the cost of transmitting an extra nibble or two to the satellite.

Is this PBL GPS format set in stone or will it be updated. It seems that the PBL GPS transmit format was instigated prior to GPS SA being turned off.