[en] The effect of Sn-doping in (Pb_0.6Sn_yCu_0.4-y)Sr₂(Y_1-xCa_x)Cu₂O_z for 0 ≤ y ≤ 0.3 and 0 ≤ x ≤ 0.7 was investigated. It was established that a nearly pure 1212 phase could be obtained at 0 ≤ y ≤ 0.1 and 0 ≤ x ≤ 0.3. The obtained X-ray diffraction (XRD) patterns as well as the results of the inductively coupled plasma atomic emission spectrometry (ICP-AES) and energy-dispersive X-ray (EDX) analysis showed that the Sn-substitution was possible in the (Pb,Cu)-1212 phase. Superconductivity was observed at 0.4 ≤ x ≤ 0.7. The onset of the diamagnetic transitions varied from 10 to 30 K. The influence of the strong Pb deficiency on the superconducting properties of the samples was discussed. (authors)