Am 19.01.2018 13:58, schrieb Paul Nicholson:
The low S/N on H is caused by high
noise floor.
Recently i thought about that...
You told us that you are climbing regularly. So there seems to be a
mountain near your QTH. Wouldn't it be possible to place the loop
antenna (at least for a test) high on the mountain, including a Raspi,
octo, GPS, batteries, solar modules, and a GHz link? Like i do on the tree.
You could carry a big metallic box up there and paint it in the colour
of the surroundings, like rocks (grey). Put some stones into the box so
that no one can carry it away. And then put the electronic stuff inside...
If you like to climb, you could use LiFePo4 batteries to recharge the
batteries once per week, if necessary.
At least it would be an exciting project. You can only win. And it is
the perfect combination of your hobbies.
It is not the rx but I think there are too many
mains harmonics going into the sferic blanker.
Did you run some trials to determine the best (for getting a SNR as good
as possible) filter settings for the harmonic notch filters?
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.
Very well. A most useful investment of time.
73, Stefan
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