May 19, 2008

What is HF SSB?

Do you require Long Range Communications?

HF SSB is the answer

HF means High Frequency whereas SSB means Single Sideband

HF & SSB radios are capable of providing communication over hundreds to thousands of Kilometres.

Buy our high frequency Codan Products at Comm Spec

HF provides communication beyond the range that is possible with conventional VHF/UHF systems, which rely on the line-of sight between communicating parties. HF on the other hand, achieves long distance communication by bouncing its signal off the ionosphere (sky waves) as shown in the Diagram below. Until recently there had always been a dead space of roughly 70 -220 Km between the point where the ground wave terminated and the point where the first sky wave returned to earth.

Standard Base Station Antenna Propagation

This operational shortcoming is unacceptable and a solution has been found by using the NVIS System. Under this system, the antenna radiates a signal near vertically up to bounce down off the ionosphere, thus providing an uninterrupted footprint from ground "0" to a radius of 6,000 Km or more.



NVIS Base Station Antenna Propagation

This operational shortcoming is unacceptable and a solution has been found by using the NVIS System. Under this system, the antenna radiates a signal near vertically up to bounce down off the ionosphere, thus providing an uninterrupted footprint from ground "0" to a radius of 6,000 Km or more.

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