Very interesting reading all the comments . . .
Bear in mind that MY Dipoles have always been pretty low, around 50ft. Also
that the British stations I have done proper comparisons with all have
decent verticals, typically at least 70ft high and over 40 quarter wave
radials. (you would recognise their callsigns)
I personally suspect that having a poor ground under such a low dipole would
cause it to have more low angle radiation than EZNEC predicts (ie the
antenna "thinks" it's higher). This seems to be born out by the fact that
people who have a Dipole that is over a radial system (for their vertical)
DOESN'T seem to work so well for DX as mine does.
So although having my own Vertical AND a Dipole to compare would be great, I
would only consider it if I could get the Dipole a long way away from the
radials. (in practice I could never get a proper set of radials out, nor
could I go high enough - I live in a very ordinary street with a
normal-sized garden, so one leg of my Dipole goes across the street!)
I do at least now have a Receiving Loop in my Loft, which is vertically
polarised. (and has a pre-amp, set to make local signals the same strength
as my Tx antenna). It's very interesting to note the difference on signals
switching between the two. Occasionally, there can be 10dB difference . . .
but MOST of the time, DX signals are exactly the same strength on both
(which supports my 2 theories)
However, based on my signal reports from DX stations, it does seem that my
low Dipoles have always worked much better than most of you guys in NA that
have tried them . . . so I wonder why that is? Is it down to these
Geomagnetic lines?
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