We were treated to a fascinating evening by Jim Bacon – G3YLA, who is world renowned for his research into Sporadic-E propagation, which can produce exciting long distance openings on the upper HF and VHF bands.

As we are just entering this year’s sporadic E season, his talk came at the perfect time to help us understand how best to experience this fleeting but effective mode of propagation.

Jim expained that Sporadic-E is a complex yet rewarding subject, influenced by many forces of nature.

It still holds many mysteries, making it a rewarding subject for those with an enquiring mind.

Jim narrowed down the main factors which produce sporadic-E openings to:-

• Meteorite trails, the ‘seeds’ of Es, containing long-living metallic ions, capable of reflecting radio waves.
• Jet streams, whose complex interactions and vortices can concentrate the density of the meteorite’s metallic ion remnants, further enhancing their ability to reflect radio signals.
• Atmospheric Gravity Waves, providing further energy input to compress and move the layer of particles to altitudes which can further enhance the propagation benefits of the Es layer.

Other influences include storms, weather fronts, ridges and the KP index. A high Kp index is harmful to the formation of sporadic E conditions, due to its disruptive energy. Ideally, we need calm solar conditions to allow the Sporadic E active layer to form.

 

Jim recommends you keep an eye on propquest.co.uk which he has developed and fine tuned over many years to become a uniquely useful tool for everyone interested in propagation

His ‘Es Probability Index’ (EPI) will give you a good feel for the likelihood of Es conditions being available in the short term.

Also look for ridges, storms and a high FoEs value.

We can expect the useful frequency to be around 8-10 times the reported FoEs value.

Openings tend to occur twice daily. Early, just after dawn, when most meteor activity occurs and later in the afternoon, due to diurnal atmospheric tides.

Keep your receiver tuned to 50.095Mhz during May to August and you will almost certainly be rewarded, with patience, with a Sporadic E opening – this could be the start of a whole new fascinating aspect to your hobby!

Good luck! And thank you Jim, for a really fascinating talk!

This evening the assembled members chose the RSGB 2024 Convention video by Don Beatie, G3BJ titled ‘Spanning the Globe, the dawn of global radio communications’

Don began by saying this isn’t a long time ago, you know. He said he had been licensed 60 years so not very short of the one hundred years we now celebrate as the first radio contact between New Zealand and the UK.

It all came about when Cecil Goyder, (G)2HM an under graduate at what is now the Imperial College London and Frank Bell, a sheep farmer in South Island NZ made a two way radio contact one hundred years ago in October 1924. The frequency was 3.2MHz!  Of course all transmissions were made at such a low frequency back then.  

Putting all in context, Don said ‘Marconi’s Atlantic leap’ had only happened 24 years before. That was spark transmission and a coherer progressing to valves. Wireless Experimenters numbers were growing and problems due to increasing interference due to the spark transmissions, the Post Office imposed restrictions. Through all this came the ‘Great Leap from UK to NZ’

Don took up 11 key points between 1898 and 1927 which saw progress in radio design and operations.

The entire story can be seen on You Tube by looking up 2024 RSGB.org/conference, and find the title ‘Spanning the Globe, the dawn of global radio communications’ by Don Beatie, G3BJ / G5W
 
 

A group gathered to hone their Morse code receiving skills with Richard G3NII and Ken G4YRF operating the keys.

We also had a demo from Victor G3JNB, allowing us to hear his amazing little all-band all-mode receiver in action. We strung up a simple wire antenna and signals from all over Europe were heard coming in loud and clear on 20m CW and 40m CW. The receiver also performed impressively on Band II, the FM broadcast band, with Classic FM crisp and clear.

We later had a small huddle, discussing plans for our forthcoming outdoor demo station at the Shefford Summer Fete, on 1st June 2025.

Ken then showed us a fine AI-generated poster on the notice board, which he and his son had prepared, to publicise our club to other users of the hall.