The complex AC impedance Z of superconducting YBa2Cu 3O7 triangular networks exposed to a perpendicular magnetic field was measured with a two-coil mutual inductance technique. At temperatures close to the transition temperature, both the imaginary and the real parts of Z as a function of the magnetic field show oscillations resulting from flux quantization in the unit cell of the network. The limited number of oscillations observed is probably an indication of the reduction of the superconducting phase coherence by disorder and inhomogeneities in the network.