NEW - Paper on NVIS propagation and the extraordinary wave mode, with analysis of 5MHz beacon data, presented by Dr Marcus Walden, G0IJZ, at the IET 11th International Conference on Ionospheric Radio Systems and Techniques (IRST 2009) (This paper is presented in PDF format which will open in its own browser window)

As we are aiming to produce an analysis of which we can all feel proud, and as the analysis is seen as a complex task, involving a large amount of work and needing a wide range of skills, we see this as a collaborative task in which we need many, with a wide range of skills and expertise, to contribute.

A few years ago a collaborative project of this nature would not have been so easy, but a high-level of adoption of computer and Internet technology by radio amateurs makes it possible to make big strides forward in terms of analysing data from an experiment of this nature.  This technological advance allows the skills, experience and time amongst the radio amateur community to be combined with those prepared to collaborate who are non-radio amateurs, but who have the necessary skills or expertise and who are keen to participate.  It was this concept of a collaborative project that encouraged the RSGB 5MHz Working Group to set up the experiment in the way that it did - an experimental technique whereby we would collect a large amount of data, with the idea that this would be analysed later to see what conclusions could be drawn.  Thus, a large data collection activity would be followed by a collaborative analysis task.  This approach is rather different to the more normal scientific method of designing an experiment to validate (or otherwise) a specific hypothesis, however, it is an equally valid method of approach.

Individual analysis & support utilities

Whilst this web-site is encouraging participation in a group analysis activity it needs to be pointed out that Individuals are free to access the tables that make up the 5MHz database and undertake their own analyses.  Whilst we are mapping out an analysis approach for the group activity, we don't want to stifle creativity and innovation, hence our desire to allow people to experiment with their own analysis methods.  We would encourage such individual approaches to discuss ideas and share their findings with the analysis group.

To enable individuals to perform their own analysis the data can be viewed and/or downloaded by following the link on http://www.rsgb.org/spectrumforum/hf/data.php.

One of the useful tools, which one of the 5MHz experimenters has kindly made available, is the data visualisation toolset on G4IRX's website.  Nick has been running a real-time beacon monitoring webpage for some while that allows instant comparison of beacon reception across the country along with a copy of the Chilton ionogram and the GOES X-ray Flux data.  This allows instant comparison and the ability to postulate possible effects such as Sporadic-E, NVIS paths, etc.  In addition Nick also provides some useful utilities for work with the 5MHz database tables, which he has running in the background on the website.  This contribution we are sure will be of great help during the initial stages of the more complex analysis planned.

Recent presentations on the 5MHz Experiment

As further background reading the following presentations on the experiment can be downloaded:

HFC2004 5MHz Forum presentation (102kB pdf, slides only)

5MHz Experiment (906kB pdf, presentation to the Surrey Radio Contact Club, Nov 2004 - slides and notes)

NVIS & the 5MHz Experiment ( 1.5MB pdf, presentation to Crawley & District Radio Society, April 2005, slides only)

HFC2005 5MHz Analysis presentation (2MB pdf file, slides only)   

Click http://www.adobe.com/products/acrobat/readstep2.html for a free Acrobat Reader if you don't otherwise have an application to display the above pdf files.