VK2RK
Active member
I keep getting reports on the day of the net that I am not as strong as I used to be, well nothing I can do about it the propagation is what it is.
It seems to me that many don't understand how the signals is travelling on this band, there is no ground wave as many think, all short distance is done via NVIS (Near Vertical Incidence sky wave) The ionosphere E layers must be in such a condition to reflect high angle waves, its these waves that allow communication with in 100 to 400 Km at night. The condition of the E layers are very depended on the activity of the sun, thus the situation of propagation is not constant and will very accordingly.
For proper NVIS communication the antenna must have a high angle of propagation, systems using low angle will suffer from low signals the most.
Its as simple as that.
The night on the net (15 Feb 2023) the band was moving by +/- 30 dB at my receiver when listening to a station running 400 watts.
.
It seems to me that many don't understand how the signals is travelling on this band, there is no ground wave as many think, all short distance is done via NVIS (Near Vertical Incidence sky wave) The ionosphere E layers must be in such a condition to reflect high angle waves, its these waves that allow communication with in 100 to 400 Km at night. The condition of the E layers are very depended on the activity of the sun, thus the situation of propagation is not constant and will very accordingly.
For proper NVIS communication the antenna must have a high angle of propagation, systems using low angle will suffer from low signals the most.
Its as simple as that.
The night on the net (15 Feb 2023) the band was moving by +/- 30 dB at my receiver when listening to a station running 400 watts.
80-meter NVIS antenna
0x9900.com