> what do you think about that GPS module:
> http://www.amazon.de/dp/B00U3N5LKI/

No PPS so not much use for this application.  You
would definitely need a 1PPS output. Look for GPS
based on one of the the LEA-6 chips such as

 http://www.amazon.de/dp/B017T0WP42/

I haven't tested that board and you can find cheaper ones.

I use several of these


http://www.mouser.co.uk/search/ProductDetail.aspx?R=0virtualkey0virtualkeyMIKROE-362

Remote receivers are a bit of a problem.  You need
a CPU and a GPS, so you end up taking a lot of digital
noise out to the quiet location.

> Better hang it into the trees :-)

Yes I have several 100m reels of wire which I could put
up.  There are plenty of trees but not very tall.  Still,
the wire is better in the air than wound around a bucket.

> ... a LF grabber showing spectrograms for QRSS60 (22 mHz)?!?

I found a bag of MC1496 in my junk box, they'll come in
handy.  There are two spare pairs in a cat5 running out
to the antenna site.

The bit I haven't figured out is how to make an interactive
spectrogram where you can scroll across the band and along
the time axis using the mouse - like we do with Google Earth
and other mapping programs.   The LF band is a lot wider
than the little piece of VLF displayed by fbins

 http://abelian.org/vlf/fbins.shtml

so I'd need to use jquery or something like that and generate
the spectrogram image on the fly.  It's certainly more of a
computing challenge than a radio project.

--
Paul Nicholson
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