Pre-emphasis and de-emphasis networks can improve the quality of television transmission using PCM technology. By optimizing these networks, the amount of noise in the video signal can be reduced, resulting in clearer pictures. The study found that with the right pre-emphasis network, the quantizing noise in the video band can be decreased by about 3.7 dB, which is like adding half a digit to the picture quality. Networks designed to mimic the optimal pre-emphasis and de-emphasis networks showed a noticeable improvement in picture quality compared to systems without these networks.