fs = 100
    T = 1
    y, _ = sin(f=10.2, T=T, fs=fs)


    for f_2 in np.linspace(11.4, 15.5, 9):
        t = np.arange(0, T, 1 / fs)
        y_2, _ = sin(f=f_2, T=T, fs=fs)

        s = y_2 + y
        S, F = spect_dB(s, len(s), fs)

        hann_win = signal.windows.hann(len(t))
        hann_win = s * hann_win
        S_wnd_hann, F_hann = spect_dB(hann_win, len(s), fs)

        hamming_win = signal.windows.hamming(len(t))
        hamming_win = s * hamming_win
        S_wnd_hamming, F_hamming = spect_dB(hamming_win, len(s), fs)

        blackman_win = signal.windows.blackman(len(t))
        blackman_win = s * blackman_win
        S_wnd_blackman, F_blackman = spect_dB(blackman_win, len(s), fs)

        plt.figure()
        plt.plot(F, S, label='Rectangle')
        plt.plot(F_hann, S_wnd_hann, label='Hann')
        plt.plot(F_hamming, S_wnd_hamming, label='Hamming')
        plt.plot(F_blackman, S_wnd_blackman, label='Blackman')
        plt.legend()


    plt.show()