In this paper we present the study of two overdoped compounds of the (
Tl1-xPbx)Sr2CaCu2O7 system by O-17 NMR. From the thermal variation of
the O-17 linewidth the presence of localized magnetic moments has been
detected, these magnetic moments being located in the conducting CuO2
planes. The comparison of the Curie constants deduced from NMR data f
or the overdoped sample (T-c = 65K) and for the heavily overdoped samp
le (T-c similar or equal to OK) is discussed.