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Special page devoted to
Mysterious Cases of Absorption of Radio - Waves
01- 2006, # 008
Cases of Absorption ofRadio - 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 98:
“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 whichwas 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 cold front…”
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.