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Current Conditions
Solar X-rays: 
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Geomagnetic Field: 
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Ionospheric foF2 Parameter (Critical Frequency) - HF&VHF Propagation Conditions and Solar Data
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UT or more specifically UT1 (Universal Time) is a time determined by the rotation of the Earth.
UTC (Coordinated Universal Time) is a clock (TAI International Atomic Time) based time and the
foundation of civil timekeeping. Occasionally seconds (Leap seconds) are added to compensate
for the slowing of Earth's rotation, so that UT1 and UTC diference is not more than 0,9 sec.
UTC: 25-04-2024 Local time: Winter (UTC+2h) & Summer (UTC+3h)
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Maximum Usable Frequencies (MUF) for 3.000 Kilometer Radio Signal Paths
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Clarifications
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The Ionosphere is a region of the upper atmosphere. Is a shell of electrons and electrically charged atoms and molecules that surrounds the Earth, stretching from a height of about 50 km to more than 1.000 km.
Includes the thermosphere and parts of the mesosphere and exosphere. Is distinguished because it is ionized by solar radiation. Owes its existence primarily to ultraviolet radiation from the Sun.
Plays an important part in atmospheric electricity and forms the inner edge of the magnetosphere. Has practical importance because, among other functions, influences radio propagation to distant places on the Earth.
Ionosphere layers are, the inner D layer (60 km to 90 km), the middle E layer (90 km to 120 km) and the outer and densest F layer or region (200 km to more than 500 km). E and F are the basic layers that refract radio waves. This refraction varies, depending on seasons and if it is day or night.
At night the F layer is the only layer of significant ionization present, while the ionization in the E and D layers is extremely low. During the day, the D and E layers become much more heavily ionized, as does the F layer, which develops an additional weaker region of ionisation known as the F1 layer. The F2 layer persists by day and night and is the region mainly responsible for the refraction of radio waves.
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Worth noting that, in the E layer sporadic and especially in the summer, areas strongly ionized are created in cloud forms. These clouds are known as Es (Sporadic-E) and have the capacity to refract waves up to 150 Mhz, rare and higher frequencies. They last from a few minutes to several hours, are moving and are the best for radio amateurs, who thus manage to transmit over much greater distances than usual.
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Critical Frequency foF2 is the highest frequency, for the ordinary wave, which is refracted by the F2 ionospheric layer.
Maximum Usable Frequency MUF is the highest frequency that can be used between two points via refraction in the ionosphere.
The magnetic equator is where the magnetic field is horizontal and the magnetic dip is zero.
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Personal Weather Station at Kato Pylea
