There are several lines of evidence that active galactic nuclei (AGN) can beregarded as scaled-up X-ray binaries (XRB). The timescales of the evolutionaryphenomena in these two classes are proportional to the black hole (BH) masses.Consequently, unlike in the case of XRBs, the evolution of AGNs is too slow tobe followed directly. What could be done, however, is to assign particulartypes of active galaxies to different evolutionary stages observable in XRBs.We studied such an assignment for three quasars with clear signatures of arecent transition from the radio-loud to the radio-quiet state. The quasars weinvestigated have large-scale radio lobes that are clearly asymmetric -- onelobe is of Fanaroff-Riley II type, while the other one is a diffuse relicdevoid of a hotspot. We suggest that the prime cause of the asymmetry of theseradio sources is that the nuclei of their host galaxies currently produce nojets. To prove that, we observed them with milliarcsecond resolution to checkif they are similar to those in radio-quiet quasars. The observations carriedout with the EVN revealed that the nuclei of the quasars under investigationare not of a core-jet type that is characteristic for radio-loud,lobe-dominated quasars. It follows that the lobes are no longer fuelled andthat the apparent asymmetry results from the orientation, which causes a timelag of the order of 10^6 years between their images: the lobe perceived as arelic is nearer than the lobe with a hotspot and so it is observed in a laterstage of the decay. The three AGNs under investigation were radio-loud earlier,but now they have switched to the radio-quiet state. In the framework of theXRB/AGN unification, the above means that they have left the very high stateand have moved now to the high/soft state. (abridged)
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