There are eight analog signals, each of bandwidth B=4kHz. Samples of these signals are time-division-multiplexed, quantized and binary-coded. The step size Δ of the quantizer cannot be greater than 0.1% of the peak amplitude mmax. Then the minimum number of quantization levels should be L=2000 . The transmission bandwidth is BT= kHz,if 64-ary PAM system with raised-cosing spectrum (roll-off factor r=1/4) are used, where the sampling rates must be at least 50% above the Nyqusit rate.