Magnetization and current noise in Hg-1201 and Tl-1223

Magnetization and current noise measurements are reported in Hg-1201 and a substituted Tl-1223 system. The temperature behaviour of the voltage noise in Hg-1201 is similar to YBCO, with large peaks at the weak-link transition. In Tl-1223, a original two peak noise specrum at fields of 250G is observed, not explained by percolative models.