We are offering delta, adaptive delta mod, demod trainer. On - board 250hz, 500hz,1khz, 2khz sinewave generator sampling rate of 8khz, 16khz, 32khz, 64khz on - board compander & expander on - board gain integration setting on - board 4th order butter-worth lpf study of delta modulation & delta demodulation study of slope overload & increased integration gain in delta modulation study of adaptive delta modulation and cvsd.