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An operational system for image transmission through the ionospheric channel is presented. For a range of 780 km, the 'high' data transfer rate attains 30 kbits/s in a 9 kHz bandwidth with the implementation of a blind spatio-temporal equalisation based on the constant modulus algorithm. This value significantly exceeds the current standard for HF modems (4.8 kbits/s). The quality of the transmitted images appears to be good compared with the original.