How to determine the source of interference in the image?

Question

CCTV

The signal passes through a twisted pair cable through baluns, the length is 150 meters. Unable to determine source of interference. The supply voltage on the cameras is 13.1 and 12.9 volts. The signal voltage near the cameras is 0.5 volts. Vertical colored line moving to the right.

Answer 1

A synchronous alien video signal is a fixed pattern of a dark or light “cross” or stripes corresponding to the quenching impulses of the alien signal. When the main and interfering signals are in phase, the quenching pulses are not visible, but the difference in the pictures can lead to a smooth color moiré.

My friend's experience, only personal experience. Try the scorched earth method, turn off all cameras, leave the problematic one. Change the power supply, disconnect the power and video signal minus. Write in as much detail as possible how video surveillance is organized: brands of cameras, regs, baluns, how many cameras are on one line, on one twisted pair, which power supply.