Why is the CCTV camera noisy?

Question

CCTV

Good afternoon!
Installed color no-name CCTV cameras. A day later there was a noise in the form of flickering horizontal stripes on the first of them; Two more joined the next. The problem is definitely not in the registrar, the supply voltage is 12v.
What can be wrong?

Answer 1

so look, you have an analog camera? I strongly advise you to deal with nutrition. As we did, the cameras were at a fairly large distance from the recorder, a DC / DC 24/12 stabilizer was poked right next to the camera, and, accordingly, 24V was given to all cameras, so there was no voltage drop and the camera felt great. Plus a good wire with a high quality factor of the RF cable, some kind of KVK but only with a thick cable for the video signal.

Answer 2

Most likely 50 Hz noise from the electrical network (since there is no example - I'm guessing on coffee grounds).
The case may be in: poor shielding of the wire, close passage to electrical wiring, unstable power supply, malfunction of the camera itself.
This is normal for analog cameras.

Answer 3

Could it be overheating?
If you turn it off for an hour and turn it on, does the noise disappear?

Answer 4

See if the BNC connectors are well-terminated. Cameras often strip due to poor braid contact. We, too, suffered from this at one time.

Answer 5

The problem is in the shielding. If the cameras are attached to metal structures - make a plastic / wooden spacer. Ground the recorder, spread the wires from the electrical cable routes. At least start with this.