When several UK stations used loop antennas, I noticed that they had fading
at much shorter distances than those using Marconis. This was at about
300km, whereas Marconi users experience fading at about 500km.
Possibly due to lower output?
Since this type of fading is caused by interference between the sky wave
and ground
wave, it suggests that the loops had a higher angle of radiation. Is this a
function of loops,
or is it possible to steer the vertical angle by altering the feedpoint?
No. Unlike high frequency, so-called 'large loops' (due to the size/WL
ratio), low frequency loops are 'small loops' and have equal current
throughout. Therefore the location of the feedpoint does not effect the wave
angle.
Bill A
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