Radio Center No. 5 in Kaliningrad began programs "Радио России" at a frequency of 549 kHz.

ПриI eat sinpo at 24233. The signal level for receiving from a car in St. Petersburg is not enough. There are level fluctuations. Perhaps the passage plays a role. At the same time, intelligibility also varies depending on freezing (QSB) and local interference from trolleybus and tram lines.

Middle Antenna of the Radio Center No. 5 of the village. Bolshakovo good - height 257 meters. The transmitter is a powerful RV -372 (during the test, the power is reduced to 100 kW).
To "перестройки" broadcasting 549 kHz was carried out from the radio center No. 11 "Krasny Bor" in the Tosnensky district of the Leningrad region. Now broadcasting has shifted to Kalinigrad, because, in my opinion, in St. Petersburg there is enough frequency of 99.0 MHz.

Many Mark the difficulty of taking PP at 549 kHz:"Очень сложно, слов не разобрать".

Record 549 kHz, a video from a car made today at 09:45 Moscow time I am attaching below.

The spread of medium waves is round -the -clock when transmitting the earth (pressed to the surface of the earth), and smoothly damped from the distance according to the Law 1/R ^{2 </ Sup>. Over 400 km, the reception is possible with a spatial wave, which is repeatedly reflected from the ionosphere, layer E, and the Earth. The presence of a layer E strongly depends on the time of day (the best reception in the evening and night hours). In the afternoon, the E layer is blocked by the absorbing ionospheric layer D. In my case, as I think, the mechanism of spreading a spatial wave. As far as I understand, for medium waves, a spatial wave (up, or at an angle to the layer E) is undesirable for radio broadcasting, therefore, the antennas of vertical polarization with a direction of direction in the vertical plane pressed to the ground are used. According to ITU graphics, with an average soil with relative dielectric permeability ε = 10 and conductivity σ = 10 -2 </ Sup> S/M (1 MS/M), an earthly frequency wave of 800 kHz at a distance of 700 km is completely fades.}

The earth's wave spreads at a lower distance from the transmitter.

ITU sets the following restrictions for reliable reception of LW and MW signals:
(Source: Regional Administrative Conference on LF/MF broadcasting for regions 1 and 2, Geneva, 1975):

Minimum field strength for confident reception (ITU recommendation)

• Northern moderate zone, day, village - 1413 μV/m (63 db/1µvm)
• Northern moderate zone, night, village - 3548 μV/m (71 db/1µvm)
• Northern moderate zone, night, city - 7079 μV/m (77 db/1µvm).

Higher requirements for field strength at night are associated with interference from distant stations operating at the same frequency.

If we take the field strength 1413 μV/m (63 db/1µvm, for the transmitter 1 kW according to the schedule.

The following ranges (service areas) are obtained for various transmitter power
For work during the day (63 db/1µvm):

The real values ​​of the propagation distance with an earth's wave above ordinary soil (ε = 10, σ = 0.01MS/m) are closer to the distance "суша". Which allows you to draw an approximate zone of coating of a transmitter from Kaliningrad. You can expect coating in the daytime of the day of the entire baltic sea, and in land the range of the earth's wave is much smaller than above the sea.

"Радио России" he broadcasts in St. Petersburg in the FM range at a frequency of 99.0 MHz with excellent quality. The radius of the coating on the VHF is determined by the direct visibility from the transmitter and for broadcasting vdings is about 100 km. Confident technique 99 FM covers St. Petersburg and part of the Leningrad region.

Distance between St. Petersburg and Kaliningrad is 826 kilometers in a straight line.

Far reception of the Kaliningrad transmitter 549 kHz

The next text is a forecast based on the study of facts and materials (not modeling).

With long distribution of medium waves, reflection from the ionized layer of the Eononosphere is used.

The height of the layer E:

• in the afternoon 80 km (shielded by the absorbing layer D at a height of 60-80 km)
• at night 100-110 km (the E layer is not shielded).

Absorption of medium waves in the ionosphere

In the afternoon - a strong absorption with the layer D. The absorption in the morning and evening hours depends on the solar activity (the number of spots on the solar disk), on the electronic concentration, the length of the beam in the absorbing layer, the anti -aircraft angle (height) of the sun, the latitude of the receiver and the transmitter, the season (winter/summer) and the frequency of the transmitter.

Local conditions

Local conditions (the sensitivity of the receiver, the presence of interference, the height of the reception point, city conditions, obstacles or their absence), the conductivity of the soil also play a role. As a result of these various factors, the final value of absorption is obtained.

Field norm for dx reception of medium waves

The permissible field tension during the distant reception of medium waves is 14 times (11DB) lower than when "земной" the wave, and is 100 μV/m (0.1 mv/m). With this level, the signal is located above the noise of 2 dB (that is, a rather mediocre level of audibility, which allows the dictator's words with difficulty). MW DX is intended mainly for enthusiasts for whom the fact of admission is important. The signs of the signal are not taken into account at the same time.

Link length and maximum field strength

В нFull time of the day should be observed with a spatial wave, as in short waves. Since the height of the layer E is 100 km, the jump is shorter than from the F2 layer. The maximum field strength at night on medium waves according to mwcircle.org is observed at distances of 200-400 kilometers.

The radius of 400 km is applied to the map:

The actual, not the calculated attitude of the signal/Shum depends on:

• daily rhythm of passage (evening/night/morning)
• time of year (the best reception from January to March, the worst - in the summer)
• Improving the passage during sunrise and sunset
• Unaccounted factors (the sensitivity of the receiver, industrial interference)
  (Source)

My forecast DX frequency reception is 549 kHz

With a power of 100 kW, with reduced quality, a frequency of 549 kHz is possible at night at night countries closest to the transmitter (can be checked using Web SDR 0-30 MHz) -Kiwi SDR:

• Russian Federation (from the west of the Pskov region - at a distance of 530 km: Pylovo, Sebezh - to the east)
• Denmark
• Germany
• Poland
• Czech Republic
• Slovakia
• Ukraine
• Belarus
• Lithuania
• Latvia
• Sweden

What power is the transmitter "Радио России" 549 kHz?

Addition: 15 minutes before the end of the hour, at 18:45 the same day the signal level increased and the reception improved to the level of frequencies of 999 and 1143 kHz.
Apparently, the engineers at the end of the dough briefly turned on the capacity above the long -term 100 kW.

By unofficial information:

Source of News - Forum vcfm.ru:

• [VCFM, ru - The topic of DV and SV in Russia] (https://forum.vcfm.ru/viewtopic.php?f=6&t=78&start=4920#P172481)

Links:

• [Search on the Internet on the Test topic "Радио России" 549 kHz from Kaliningrad] (https://duckduckgo.com/?q=549+%D0%BA%D0%93%D1%86+%D0%BF%D1%D0%B8%D0%B5%D0%BC&TB=V394-1&IA=WEB)
• [On the influence of soil conductivity on the spread of medium waves] (http://www.wabweb.net/radio/radio/grundl3.htm)
• [Handbook of Ground Wave Propagation] (https://www.itu.int/dms_pub/itu-r/opb/HDB/HDB-59-59-20-PDF-E.PDF)

Free map:

• Flat World Map Vectors by Vecteezy

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