Initial commissioning observations for the C-band (4-6 GHz) receiver showed a variation in measured Tsys/Tcal across the 40 and 20 MHz passbands which can appear to be a ripple in the Tsys/Tcal spectrum of a receiver if spectra are concatenated. The amplitude can be as large as 10% of the system temperature. This has probably colored the baseline measurements made with other receivers. Comparisons between the spectral processor and the spectrometer suggest that this ripple probably resides in the spectral processor. Also, since the magnitude of the ripple is a function of input power level it appears that this effect may be related to the quantization. The wavelength of the ripple matches the spectral processor bandwidth and the amplitude appears to increase with bandwidth.