Critical properties and structural features have been studied using co
mposite tape sliver sheathed Bi-2223 base superconductors manufactured
by ''powder in tube'' method from precursors containing phase Bi-2212
in the range of 0-90%, The critical current densities of 4 x 10(4) A/
cm(2) (77 K, O T) and 1.3 x 10(5) A/cm(2) (4.2 K, 5 T) have been reali
zed in tape superconductors 0.18 mm x 3.4 mm in section produced from
a precursor containing 50% phase Bi-2212. A small pancake coil compris
ing 60 turns was processed by ''wind and react'' method using tape wit
h optimized powder.