Abstract: A signal-to-noise improving system is described which comprises a circuit input for incoming noisy analogue signals and a circuit output for digitally stored input signals which have an improved signal-to-noise ratio provided by the system and which have been reconverted to analogue form,said circuit input and said circuit output being connected to inputs of an analogue comparator arranged to give an output which signifies that the stored signal is either higher or lower in magnitude than the incoming signal or that the incoming signal is either higher or lower in magnitude than the stored signal,said comparator output being connected to a signal incrementor which is arranged to give a signal output which is the stored digital signal incremented higher or lower by a number digitally in response to either a higher or lower signal output from said comparator,a store for storing in digital from the so incremented input signals, the store output being connected to a digital to analogue converter 1 the output of w