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Mysterious Cases of Absorption of Radio - Waves
01- 2006, # 008
Cases of Absorption of Radio - Waves
The publication had lot
of feedback. One of readers, A. K. Pastuhov
from Podmoscovie, has presented me used, but accurately bound
book of D. N. Nasilov "Radiometeorology." The book was in my references list.
Quote from the book, page
"At flight of June 9, 1936 at , above Moscow on a plane through cold air front took
place breakage of communication. When the plane go through the
cold front, radio operator did not hear Moscow HF station which
was on the reverse side of the cold front on distance 15 km from
the plane, but they heard very loud HF radio from Smolensk (several
hundreds km) that was at the same side (with the plane) of the
Lots similar cases were
written in the book. For example, was written phenomenon of losses
communication on VHF between two planes when the planes were divided
N. Nasilov explains this effect by refraction
on the layers of fog or clouds. I have accepted this explanation
as a working hypothesis. Recently, attentively read all feedback
on my article, to Kovalev article (Reference 1) and with publication by I.
Grigorov "Antennas in the mountains"
(Reference 3)I understood that the explanation
is not enough. Not any fog or cloud strongly absorbs radio waves.
We need some more conditions.
I believe the main condition iselectrization of drops of clouds or fog. To absorb radio waves
the fog or cloud should have conductivity. At this case, the cloud
not only screening antennas, drops of the cloud absorb energy
of the wave. In depend of the sizes of drops the cloud may have
frequencies of heavy absorption. The frequencies may be at LW,
MW, HF or VHF ranges.
can be called the by the different reasons: flares on the Sun,
tectonism, and so on. However, probably, the main reasons
of the electrization are in process of evaporation - condensation
(that, in particular, results to electrization
of clouds) and in downpours of space particles, which are common
at poles and in auroral zones, where,
accordingly, we notice more cases of abnormal absorption.