Upper panel: all the observations collected to estimate physical parameters of PG 1004+130 and the selected positions of the self-absorption frequency, the synchrotron peak, and the IC peak with the assumed uncertainties. Lower panel: result of the estimations and the specific values B = 0.6 G and K = 5 × 10² cm^-3 (a dot) selected for the precise calculations demonstrated in Fig. 4.