The effect of 2-level quantisation of the signals within the equaliser on its performance is studied in two cases:(a)when the tap coefficients are updated after every sample of the message, and (b) when the updating is performed after an averaging period equal to the length of a pseudorandom binary signal. In particular, the effect on the stability and the mean square error in the steady state is analysed. A relationship between the mean square error in the steady state and the ‘random walk’of the tap coefficients is derived. Numerous computer-simulation results confirm the analysis.