Two numerical solutions are given for an integrodifferential equation governing the electric field in the aperture of a parallel-plate waveguide-loaded slot antenna excited by an obliquely incident plane wave. Resultant aperture field distributions obtained via Galerkin's method with a basis of edge-condition weighted Chebyshev-polynomials are compared with the results from pulse expansion with point matching. It is shown that the relative numerical convergence of the Chebyshev-Galerkin method and of the pulse expansion-point matching applied to the receive mode of the parallel plate-fed slot antenna are qualitatively similar to a previously reported transmit case, that is, the full domain expansion with the built-in edge condition behavior converges faster than the sub-domain method, and agreement between the two independent results serves as a necessary, albeit not strictly sufficient, check on the accuracy of the implementation. >