Sunday DX Headlines will experiment with Slow Hell at 144 Hz. Another invention from before WW2. Hellschreiber was invented in Germany by Rudolf Hell in the late 1920’s. It came into use in the early 1930’s. Because it doesn’t have a fixed character set, it rather transmits small images for each character, the system also gained some popularity in Asia.
For some reason Slow Hell doesn’t have a Reed-Solomon code in Fldigi, so you will have to set Fldigi manually (to Slow Hell @144 Hz). This is a really slow one, but I estimate it will probably work quite well, partly because of the higher audio frequency and partly because the Hellschreiber is such a good system.
Sunday +/- 01:39 UTC 9925 kHz on shortwave radio, targetting US and Canada from Germany.