In this paper a hardware implementation of the finite impulse response narrow band-stop time-varying filter based on the infinite impulse prototype filter is proposed. The notch filter is used for removing power-line interferences from biomedical source, i.e. ECG signal. In order to suppress the transient state of the proposed filter, the pole radius and the pole angle of the prototype filter are temporarily varied in time. The proposed filters are tested using sinusoidal and ECG signals. The algorithm for computing the filter coefficients is presented. Computer simulations, and performance indexes demonstrate that the proposed filter possesses better properties than traditional timeinvariant notch filter. Moreover, the hardware implementation of the presented filter using Raspberry Pi platform has been presented.