|
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese|
ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING Solar activity and ultra-long-range television reception. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Телевидение Below is an article by V. Zharkov, host of the London television station in Lvov. He connects this technique with solar chromospheric flares, which, in his opinion, form a sporadic layer, and concludes that this technique is possible during high solar activity. However, measurements of the Es layer show that not only is there no direct correlation (coincidence, consistency) between the Es layer and solar activity, but in the last cycle of solar activity there was a weak inverse correlation. From 1957 to 1961, despite the fact that the activity fell more than twice, the electron density of this layer remains at the same level. As is known, chromospheric flares occur from March to September, while long-range television reception is more often observed from May to August, during the same period the electron density of the Es layer is the highest. In the summer season, chromospheric flares that strongly affect the ionosphere are rare - no more than 2-3 times a month, and a high electron density of the Es layer is observed almost daily. Chromospheric flares affect the ionosphere mainly in the illuminated hemisphere, while distant television reception, although less often, is possible both in the evening and at night ... A satisfactory explanation of the nature of the Es layer has not yet been found, and Comrade Zharkov's assumption about the connection of this layer with chromospheric flares is of interest, but further observations and comparisons are required. It is well known that ultra-long-range television reception usually occurs in the summer months and mainly due to reflection from the ionized Es layer, the structure and origin of which has not yet been sufficiently elucidated. It was found that cases of ultra-long-range reception of television transmissions are repeated after 27 days. The graphs (Fig. 1) compare the cases of long-range reception of television signals from the London television station (frequency 45 MHz) with solar data: the number of spots W and the frequency of chromospheric flares X. The signals were received on a fixed antenna oriented to the local television center (Lvov ), located approximately 80 km south of the observation point (the city of Sokal). Thus, the signals of ultra-long-range stations were received as interference to the local television transmission.
As can be seen from the graphs, the frequency of cases of ultra-long-range reception of transmissions coincides with the frequency of repetition of chromospheric flares; however, two to six days elapse between the onset of flares and the formation of an ionized cloud. This "lag" time depends on both the average rate of development of outbreaks from the beginning to the maximum (tg Xcp) and the average rate of development of spot formation (tgWcp). The effect of solar flares on the ionization of ionospheric layers is a fairly reliable fact. It can be assumed that the ionizing effect of solar flares should be most pronounced at 23°-14° N for the summer months. During the years of minimum solar activity, the frequency of television broadcasts, as well as the duration of reception, will be much less. If we compare the duration of reception of television signals and the total ionizing radiation of flashes, we get a direct relationship. With a large total radiation (June 10 and 11, June 22 and 23, July 3 and 4, 1957 in Fig. 1), the transmission of the television signal was also the next day. During powerful chromospheric flares, a significant increase in air temperature is also observed. In conclusion, we should note the cases when ultra-long-range reception was observed in the "absence" of flares. Indeed, if a rotating antenna and an antenna amplifier are used, ultra-long reception is sometimes possible even in the "absence" of chromospheric flares, however, such reception is very short-lived and unstable - one received station is replaced by another. etc. Such reception can occur both due to reflection from meteor trails, and from weakly ionized formations arising from cosmic rays and from weak chromospheric flares. What years will be the most favorable for long-distance television reception? As is known, the previous period of 11-year solar activity began in 1955. However, the most favorable years for long-range television reception were 1957, 1958, 1959, and 1960, that is, years close to the solar activity maximum. Thus, we can expect good conditions for long-range television reception in 1967-1968. Lviv. Author: V. Zharkov; Publication: N. Bolshakov, rf.atnn.ru
Alcohol content of warm beer
07.05.2024 Major risk factor for gambling addiction
07.05.2024 Traffic noise delays the growth of chicks
06.05.2024
▪ Helicopter with muscle drive ▪ The driver will always notice the pedestrian ▪ OmniVision Image Sensors for Smartphones
▪ section of the Radio Control website. Article selection ▪ article We are not slaves, we are not slaves. Popular expression ▪ article Which language contains only 12 letters? Detailed answer ▪ Helpline Consultant article. Job description
Comments on the article: Andrew, UT4UCJ The Es transit does not have a direct correlation with the 11-year solar activity cycle. The wind shear theory is currently the most accepted. The neutral wind in the E layer and the Earth's magnetic field play a decisive role here. Electric fields in the E layer and thunderstorms also take place. A sharp change in the weather in summer and thunderstorms predict an Es passage quite well. Moreover, there is evidence that intense sporadic layers consisting of metal ions occur more often precisely during the years of the solar activity MINIMUM, when the E layer is less dense and the neutral wind is less decelerating. And, in general, the question is very interesting and not fully understood! Andrew, UT4UCJ Andrey (UT4UCJ), samfox3345@gmail.com. There are a variety of versions of Es-passage. Someone says that these are some processes on the Sun that have not yet been studied, they also talk about the influence of lightning, upward torches and sprites, there is a version that an ordinary thunderstorm works like a heating stand, being a source of powerful electromagnetic impulses, raising the Es-MUF, and also that during a thunderstorm the regular layer E is charged and meteor dust is attracted to it, forming Es-clouds, just as small pieces of paper are attracted to an electrified plastic comb against the hair ... Magnetic storms are still different influence. There is a version that the currents flowing through the regular layer E influence and the ampere force creates inhomogeneities with increased ionization in the layer E. More detailed material on Es can be found on the Internet. What can I say, Es at frequencies above 100 MHz is really a mystery, akin to the mystery of the appearance of ball lightning, and, probably, only quantum physics will help to solve it somehow ... Scientists and ultrashortwave radio amateurs, there is a reason to conduct interesting research in this area !
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua |
See other articles Section 
Latest news of science and technology, new electronics:
All languages of this page