(Restarting the thread with a more apposite topic name) On Sun, Aug 14, 2016 at 12:47 PM, Mark Sims <holrum@hotmail.com> wrote: > The NVS NV08C GPS receiver module is a rather nice little 32 channel GPS/GLONASS/SBAS receiver that has an output message that gives you the raw satellite bit streams. They can be had for around $60 bare module ($120 on a breakout board from sylphase.com). They also support carrier phase info, sawtooth correction output, and up to 10 Hz navigation rates. > > > Lady Heather now supports the NVS08C... it was a bit of a pain to do. Several messages send values (rather needlessly) in an 80-bit floating point number format that most compilers do not natively support. Lady Heather converts those to standard 64-bit floating point values. Their binary message protocol is basically Trimble TSIP at 115,200:8:ODD:1 (with optional support for 16-bit CRC's) The NV08C also has an official board http://www.m2mconnectivity.com.au/technologies/gnss-gps/gnss-receivers/nv08c-csm-brd for about AUD100. We use these for GPS common-view time transfer (which needs the raw data). There's some performance data here: http://www.openttp.org/scripts/blog.php Cheers Michael