BARRETT 2030 HF SSB TRANSCEIVER
Radio Wave Propagation Illustrated
The following illustrations show the characteristics of ground-wave and sky-wave
propagation during day and night time. In each illustration the height of the
ionosphere above the ground is shown.
In both illustrations Station A communicates with Stations B, C and D. Propagation
from Station A to B is by ground-wave. The diagrams illustrate that the ground
wave is not affected by the time of day and the height of the ionosphere above the
ground.
Propagation from Station A to C and D, however, is by sky-wave and as the
diagrams illustrate the sky wave is significantly affected by the time of day and the
height of the ionosphere above the ground.
Under each diagram there are recommended working frequencies listed. Please
note that these will vary according to time of year and other factors. They are
intended only as a guide and are subject to change.
Day
The sun is higher, the ionosphere is higher; the best frequency to use is
higher
A to B - Possible optimum working frequency is 3 MHz
A to C - Possible optimum working frequency is between 7 MHz to 9 MHz
A to D - Possible optimum working frequency is between 13 MHz to 16 MHz
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