Abstract

A practical evaluation of the diurnal and seasonal variations in tropospheric propagation at various distances overland is described. To gather the necessary data, a 50 MHz transmitting station beaming south was established as far north in England as possible. It worked for 24 hours a day for more than a year while monitoring stations were set up in the Midlands and near the South Coast.

The survey was completed during 1996-1997 and the stations and their findings are discussed. It is surprising that although abnormal conditions are fully understood, the much more reliable normal mode of tropospheric propagation has received very little attention. Yet conditions suitable for medium distance communications are known to exist. We advance an hypothesis which we hope will serve as guide-lines towards the development of an acceptable theory.

The Background

The Experiment

Results Achieved

A Comparison with Sub-Tropical Conditions

Conclusions

The Hypothesis

Acknowledgements

Appendix

References

Editorial Note

These pages have been ported from the original disk files of the printed report. There are some shortcomings of these Web pages, in comparison with the original report. Illustrations are not as clear, as a compromise between resolution, image size, and download time has had to be struck. Some pages, particularly the Appendix, contain a lot of tabular material which may be slow to parse on your browser. Errors may also have crept into this text.

Please e-mail mechanical issues to the page creator, Howard Oakley M1BWR at howard@quercus.demon.co.uk