This question is very often asked in relation to voice connections on shortwave. eg sailing yacht "XY" in St. Lucia would like to connect with their friends yacht "AB" in Nassau / Bahamas a connection via shortwave radio in SSB.
In this case we have a small utility tool designed and (per frequency band) fed with the marine frequencies / amateur radio frequencies. This tool is calculated based on the two positions of the yachts "XY" and "DOWN" and the current sunspots and the solar flux index numbers, the optimum frequencies and times.
If both boats are now using this little tool, you always know at what frequency and at what time a radio link to 100% is possible.
It does not matter here that one has, the sunspot numbers and solar flux index, the 100% exact position of the other party do not change within a span of 2-3 weeks so, the forecast errors are calculated.
In our testing with a few beta testers, we have predicted at any time our callers can reach since October 2012.
The "Where & When" propagation tool is an absolute must have for sailors with SSB radio on board.
For the amateur radio operators of you lies a myriad of tools and programs on the net but some of them are presented as complicated and cumbersome, which makes it a little fun to work with.
Keep it simple!
- Install program tool
- PC with NMEA data feed (GPS Mouse, Raymarine, etc.)
Sunspot load from the internet -
- Enter the approximate position (Lat. and Long.) Of the interlocutors
System requirements: Windows
GPS data (NMEA) via navigation systems or GPS Mouse
A trial version is available in a few days on my website for download
Intro - www.yachtfunk.com
fair winds Joerg