Digital Noise Reduction in CCTV installation
What is digital noise?
It is inevitable phenomenon to avoid excess noise which can obscure the picture. Noise is irregular fluctuations that transmit electrical signals (electromagnet) which are not part of normal CCTV video footage and this can obscure the normal CCTV signal.
How to avoid noise?
There are many ways you can avoid noise in CCTV installation. Potential noise should be identified as early as possible at CCTV designing phrase, for example high voltage current cables, other video transmission cables (satellite cables), long cable run without ground can produce noise. Once this is identified, all measures should be taken to prevent it.
Video cable to close to Main power cable
If you are running video cable parallel to main power cable (230V or 110V AC), you should have at least 12 inch gap. Try to run CCTV cables in a separate cable tray or trunking to avoid any unwanted noise interference. NOTE: Plastic conduit and trunking do not stop noise or interference.
Poor BNC termination
Better BNC termination is crucial in avoiding noise. Sometimes it is impossible to have better crimping with poor CCTV tools, for example it is advised that you use three blade cable strippers and follow the correct measurements (15-16mm) in stripping the coax.
IP rated Junction box
Use junction box to secure BNC and DC lead termination. It is a good practice to use IP rated junction box hide connections.
Good CCTV camera with DNR
Last but not least, use quality CCTV cameras. When you buy cameras make sure they have Digital Noise Reduction feature, it is often found good quality cameras. Often it is confused with TVL’s, digital noise reduction is a different feature that many leading CCTV camera manufacturer provide.
Samsung SSNR and CubeCCTV JA-984EB are good cameras to use.
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