1, Horizontal stripes rolling up and down
This phenomenon is manifested as the relatively wide striped rolling up or down without stop. In fact, it is not caused by the outside the electromagnetic wave though it looks like interference. If you put aside the stripes, the image is clear. This phenomenon is basically accounted for more than 80% of the image interference, this phenomenon can be sure to be the problem of ground potential which refers to the existence of potential difference between the front-end equipment and control room. multimeter can not test such problems, for it does not mean that there not exist potential difference though the measured number is zero. CCTVMAN
suggests you that the only way is to disconnect the end(the best choice for front-end). If you don not want to break both of the ends for worrying about the lightning. You can add a ground loop balancer to solve the problem. As long as the passive device link to any end of the coaxial cable, it can eliminate the phenomenon of stripes. Moreover, the device is easy to install with good effect.
2, Mesh interference
The image quality of this phenomenon is poor without any objects can be seen basically. Sometimes the images do not appear, as well as the screen crash. Most of this situation take up in the connector. The condition that welding problems or poor quality of connector pieces cause interference in the project also accounted for the majority.
3, The interference of space electromagnetic waves
This interference source is more complex which mainly contains front-end equipment, cable, the strong radiation source or high-power equipment near the terminal. The interference mainly manifest the image distortion, jitter and so on. So you should be aware of the surrounding environment and try to avoid the radiation source before the construction. In the already completed construction project, you have to add the anti-jamming equipment, since the interference can not be avoided. This method is more economical, fast, and the image is also guaranteed.