> so the 100 character message is realistic between us! :-)

Perhaps.

At this frequency I have the same problem with H S/N as at 5170.

Eg, your overnight carrier in 31uHz:

  E:  S/N 16.6 dB;
  H:  S/N 11.0 dB;
  E + H: S/N 15.1 dB;

The E and H amplitudes agree well, corresponding to E/H = 326 Ohms
which is quite reasonable.   The low S/N on H is caused by high
noise floor.  It is not the rx but I think there are too many
mains harmonics going into the sferic blanker.  These are modulated
by the blanking action into a broad noise floor.

This problem can be solved I think.  Your carrier at 4470.1 is very
useful for this as a test signal.

Just now I'm dividing my radio time between this and some interesting
things with whistlers, and two construction projects.

PS, I am also making some effort to publicise amateur VLF activities,
on various social media groups.   Responses tend to indicate that
few people, even VLF enthusiasts, are aware that radio amateurs are
using these frequencies.   I hope some publicity will lead to new
receivers in new countries.

--
Paul Nicholson
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