[time-nuts] VLF time station, cheap sdrs

[jimlux]

https://www.rtl-sdr.com/tag/vlf/

a fair number of examples -

As I speculated, the 8 bit RTL-SDR has a problem with strong broadcast 
band AM, so you need some sort of LPF.

There are some examples of "amplified whip into sound card into Rpi" 
implementations.

I didn't see anybody actually decoding or measuring the phase though - 
lots of waterfall plots showing the existence of a signal.