Observation s on the 53.5-MHz auroral radar at Slope Pont, New Zealand, show that the power spectrum of the afternoon/evening diffuse radar aurora associated with the eastward electrojet consists of two different component spectral distributions, which are designated type A and type B. The type A distribution has a tendency to double peak and a width at half power corresponding to a velocity of ~300 m s-1; the type B distribution is single-peaked with a half-power width ~600 m s-1. The irregularities producing the type A distribution are centered at a height of about 106 km, those producing type B at 112 km. When viewed on an azimuth of about 25¿ east of the local magnetic meridian, the mean Doppler velocity of each spectral distribution can differ by up to several hundred meters per second on different occasions but that of type B always exceeds the mean velocity of type A. On the generally accepted hypothesis that the radar observes secondary waves generated by non linear processes from the primary irregularities in the electrojet, this difference indicates a real difference in the velocity of the primaries and/or that they propagate in different directions.