JT65 and JT9 Digital Modes on HF – Presentation

I gave a short presentation to the Saint Clair Amateur Radio Club last week regarding two “relatively” new digital modes of communication on the High Frequency bands that have been gaining in popularity.


Solar activity, as measured by the presence of sun spots, is expected to drop and bottom-out in 2020. Since sun spots contribute significantly to the ionization of the F1 and F2 layers of the ionosphere, worldwide propagation will wane as well. Modes of communication that work well at low signal levels will become more prominent during the next few years as a result.

JT65/JT9 are modes that shine when signals are very weak.  Although they aren’t designed for “rag chewing,” or extended conversations, they do fill a gap for “DX chasers”–those who enjoy making brief contact with ham radio operators in other countries.

The presentation is attached.  I followed it with a live demonstration, using TeamViewer to connect with my iPad from the club’s meeting location to my Windows PC at home which was controlling my HF radio.

JT65/JT9 Digital Mode Presentation: PDF  PPT


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