The structural and transport properties of Nd1-xCaxBa2Cu3Oy (xˆ=0, 0.03, 0.06, and 0.10) and Nd1-xLaxBa2Cu3Oy (x nominally 0.0, 0.05, 0.10, and 0.15) have been studied by X-ray powder diff€raction, electrical resistivity, and thermoelectric power measurements. In both series, the a- and b-axis lattice parameters decrease with increasing doping while the c-axis lattice parameter increases. The transport properties suggest improved metallic behaviour with increasing Ca doping in contrast to La doping. An anomalous sharp peak in the thermoelectric power close to Tc was observed, which depended on the doping content. We analysed the thermoelectric power as a function of temperature with a two-band model with an additional linear T term. An excellent agreement between model and data was obtained.

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