After some adjustments to sferic blanking:

 Eb/N0: 5.4
 carrier S/N: 21.43 dB in 82.2 uHz

So I've gone from 1.2dB to 5.4dB just by playing with the
sferic blanker settings!   It shows how very important it
is to get this right - at each band, and separately for
day and night conditions.

The 5.4 dB is with the new blanker but different settings.
It is over 2dB better than my standard 8270 blanker options!

It is very time consuming trialling different settings.  At
least it can be done, so long as you can see something of the
signal.  But with an invisible signal (EbNaut) the only way
is to insert a weak marker and tune up on that.

I've long had the thought that it would be nice to have
a -auto option to the blanker, so it can tune itself to
the characteristics of the VLF it sees.  Right now, this
goal is receding further by the day.

The more I study this, the less I know.

--
Paul Nicholson
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