Experiments with Faros software and wsjt: azimuthal errors in HF propagation

This research aimed to study a propagation phenomenon that often occurs on HF bands .It is a systematic reception where some signal arriving not from the correct azimuthal direction but from another side with a different antenna beaming (azimuthal error). It is difficult to establish exactly what cause  this difference. We are beginning from the study of some experimental test, many of this already described in a previous publication (please see the archives section on                                         (http://www.qsl.net/ik3xtv/archivio.htm). In this document I try to consider some possible explanations.The instruments used are the digital transmission WSJT  in the JT65A mode, because it is able to  trace and draw signal, and  the software Faros designed for detecting and monitoring  NCDX beacons chain.
Beacons experiments OH2B
I used a very fast internet connection with optic fiber technology connected with faros software Wich is able to detect and to show the signal delay of the beacons. The experiment has been conducted mainly on 18 mhz band, when the short skip to OH2B was closed.  I found that for a short time interval, the beacon was clearly receivable only from the south-east direction about 150 ° / 160 ° azimuth from my location. The recorded signal with Faros calculation an average delay of approximately 15 msec compared to the short path. this Means a signal path of about 4500 km. The hypothesis of a possible reflection in the area of Eastern Mediterranean or in the Sinai peninsula That is also the area of increased ionization. (map below) where the MUF in that time are increasing. The experiment conducted also on 14 MHz band with similar results, but with a shorter interval time.

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Long path experiments receiving Beacon OA4B Lima Perù

Using the system Faros with a very fast internet connection (20 MB) and very sharp checking time able to recognize  the detection of  shortpath, longpath or abnormally path. I conducted  some experiments to highlight possible hypotheses of ducting ionospheric propagation. The beacon signal of OA4B  was received only long path (the Short path  was closed) with a skip of about 30,000  km. The path was open simultaneously on  band 14 mhz  and 18 Mhz. At the same time was detected  the beacon ZL2B  from New Zealand   and VK6RPB from Perth - Australia .  It highlights a possible wave guide in the Ionosphere. As the three beacons are about  over the same geodetic line.
This propagation opening  is very short because the conditions that support propagation  changes  rapidly. May be is  possible  an adding  action of gray line enhancements.

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Contrary to what we can expect, strong geomagnetic storms  can promote propagation openings creating favorable conditions and sometimes exceptional conditions. Frequencies are most concerned the low ranges of HF and even medium waves. From the analysis of several cases emerge  that this is something really connected to ionospheric conditions disrupted as a result of intense geomagnetic phenomena. Because the random nature of Ionospheric propagation, is not possible to identify with certainty the elements that support propagation. One thing, however, is sure and is derived from years of research and listening to the radio frequencies: the classic model of propagation (ionospheric jumps) is unable to explain the phenomena that govern and support propagation. I am convinced that we should try something of different from the classical model that under a certain point of view it results to be obsolete. So I tried to make a few plausible scenarios that could explain why these extraordinary openings may occur.  One thing is  sure  that as a result of solar wind, the geometry of the ionosphere is changed. The ionosphere is compressed in the hemisphere lighted by the sun and there is a  gradual extension on the opposite side, where up most extreme to be confused with the tail of the magnetosphere. I think that this geometric variation can be favorable for the signal propagation. 

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