We have measured the conductance of Y1-xPrxBa2Cu3O7/Pb planar tunnel junctions fabricated on thin films where x equals 0, 0.2 and 0.4. When tunneling into the ab-plane, there is a weak decrease in conductance at eV approximately 2kBTc, where a superconducting gap is expected. With increasing Pr concentration, the energy where this gap-like feature appears is reduced by an amount commensurate with the reduction in Tc. The gap-like structure in the c-axis tunneling conductance becomes weaker, but displays no change in energy when YBCO is doped with Pr.
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