SiRf stuff

Hi all,
I'm having a whole lot of fun exporing my new SiRf III board.
But I can't understand the C/No1 to C/No10 values in the Messured Tracker
Data Out message ID4.
I can readily get the signal strengths from the data when in NMEA mode but
am having trouble getting them when in SiRf mode.
Perhaps I'm just a bit thick but some help would be appreciated a lot. I've
no trouble getting the values but don't know what they are and what to do
with them.
Help!!!!
Thanks
Paul C


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