Re: VLF: E-field receivers in Todmorden

[Paul Nicholson <vlf0403@abelian.org>]

Markus wrote:

> maybe in the received signal level from the Alphas?
> ... a bit of directivity due to environmental conditions

I wonder.

One curious fact supporting this is the noise blanker drop
factor.  This is the proportion of time the blanker is active.

The drop factor is always a bit higher on the new rx than
the old when I run the two signals through independent sferic
blankers.

The blanking threshold is set relative to the noise floor,
which is tracked by an asymmetric moving average.  The new rx
must have a lower threshold to have a higher blanking factor,
therefore vtblank is finding a lower floor (relative to the
sferics) on the new rx compared with the old.

So, the E-field probes are not quite omni-directional perhaps?

I need to look at more signals, from different directions,
to build a picture.

--
Paul Nicholson
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