Joe VO1NA wrote:

> A GPS unit is now on hand.  It provides NMEA strings but
> I'm not sure about the pps.

PPS essential if you're using Spectrum Lab or vlfrx-tools.

The GPS that I use these days is this one


http://uk.mouser.com/ProductDetail/mikroElektronika/MIKROE-362/?qs=sGAEpiMZZMuNcqZxhMNT368vTF1vBnGt

 http://www.mikroe.com/eng/products/view/122/smartgps-board/

After some arithmetic and comparison with other signals,
I reckon that if you can muster 40uW, it will be possible
to decode messages at 8277 Hz here the UK, and 20uW would be
enough for a carrier detection.    That assumes a suitably
precise oscillator.

--
Paul Nicholson
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