Hello Stefan,
A receiving loop will give the best signal i assume, but it is not very
easy to handle if one is always /p.
There is floating a lot of untested lore around, regarding reception
antennas.
When I started listening at LF 8 years ago, I was convinced that loops
were the way to go.
I spent a whole winter season to get them to work, but failed due to local
noise pick up.
I decided that it was impossible to get proper results in a city location
and almost gave up.
As a last resort and just for the fun of it, I build an active whip and
much to my surprise it worked.
At the time I have made a lot of tests comparing active whips and loops on
a field location. They were aligned for the same output on a local NDB on
399.5 kHz. The results were that I could not find any difference between
the loop and the whip, except the directive properties of the loop.
The poor results of the loop at home were due to the fact that the house
acts as a faraday cage for the electric field. So local noise in the
electric field is attenuated, whilst local noise in the magnetic field is
not.
At 400 kHz the attenuation was 30 dB.
In a rf-quiet location both antenna types perform equally well.
The whip has been used almost 7 years now as an ongoing experiment with
rather unexpected results. I have received with aural copy the now closed
down NDB on Easter Island in the Pacific. But I am convinced that a loop
at a good location should have given similar results.
And yes, a whip is much easier to handle when going portible; especially
when it is housed in a piece of plastic pipe measuring 30 x 60 mm.
73,
Roelof, pa0rdt
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