Variation of the core shift with frequency as obtained from our reference model. The inset panel shows a contour plot of the synthetic radio maps over-plotted with corresponding core position for different observing frequencies. In the inset panel the range from −1.5 × 10¹⁸ cm < x < 0 cm indicates the jet (pointing towards the observer) and the range from 0 mas < x < 1.5 × 10¹⁸ cm corresponds to the counter-jet.