Аннотация:The H -T phase diagrams of single crystalline electron-doped K0.83Fe1.83Se2 (KFS1), K0.8Fe2Se2 (KFS2) and hole-doped Eu0.5K0.5Fe2As2 (EKFA) have been deduced from tunnel diode oscillator-based contactless measurements in pulsed magnetic fields up to 57 T for the interplane (H ‖ c) and in-plane (H ‖ ab) directions. The temperature dependence of the upper critical magnetic field Hc2(T ) relevant to EFKA is accounted for by Pauli model including an anisotropic Pauli paramagnetic contribution (μBHp = 114 T for H ‖ ab and 86 T for H ‖ c). This is also the case of KFS1 and KFS2 for H ‖ ab whereas a significant upward curvature, accounted for by a two-gap model, is observed for H ‖ c. Despite the presence of antiferromagnetic lattice order within the superconducting state of the studied compounds, no influence of magnetic ordering on the temperature dependence of Hc2(T ) is observed.