Re: VLF: Outdoor test for different places for active E-field antennas for VLF

["Roelof Bakker" <roelof@ndb.demon.nl>]

Hello Stefan,

Many thanks for sharing your findings.
I have done similar tests at 137 kHz and 400 kHz.
In a nutshell, it did not pay off to raise the antenna 6 meter ( total  
height 12 meter) above the semi flat roof of my house, compared to 5 metre  
high in the garden as the signal to noise ratio did not improve.
Unfortunately, I did not monitor the Russian Alpha signals at the time.
I did find a 15 dB lower signal level at 11.906 kHz at my city location  
compared to a a free field location, though.
Both antennas were at the same height.

I have a few chestnut trees 20 metre away which are full with new leaves  
and blossom.
At 400 kHz they have a screening effect of 1.5 to 2 dB!

Maybe you can check the signal to noise issue again when you have a real  
signal for comparison, to make sure that your assumptions are valid.
Enjoy your weekend!

73,
Roelof, pa0rdt