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A unique set of ionospheric radioemissions in the frequency range of 0.6-6.0 MHz has been registered on board of Intercosmos-19 satellite launched in 1979, i.e., during the peak of the last solar activity period. Many new characteristics of ionospheric radioemissions have been discovered in this set. In the above spectral range of emission the Intercosmos-19 data show the following features: If fp 3 MHz and FOF2 5.5 MHz, there exists a broadband enhancement centred on 4 MHz, reaching the level of about-82dB; the shape of this enhancement shows minor variation of the order of 3 dBm along the satellite orbit in spite of broad variations of fp and FOF2, if the mentioned relations between frequencies are fulfilled; usually if FOF2 drops even to 3 MHz, the man made radionoises add independently to this enhancement - the enhancement is strongly modified when fp increases above 5 MHz and its shape is related to the changes of fp. These characteristics suggest the hypothesis on nonglobal origin on the observed broad-band emission. The aim of the present paper is to discuss this question.