As the saying goes “prevention is better than a cure” so if you’re fairly new to CCTV it's better to get things done right first time. Here are just a few simple checks to make to rule out possible interference on your CCTV system and most importantly avoid any time consuming and costly call backs to site.
Symptoms can include:
Grainy or fuzzy images, ghosting (ie, 1 image over another), screen tearing, B&W picture that should be colour, intermittent image, no image at all.
Check your voltage
Not enough power to a CCTV camera (maybe due to an extra long cable run) can result in no picture or at best unpredictable results. The latest CCTVmate Test Monitors have built in test meters perfect for such troubleshooting, making them well worth the investment.
Check your CO-AX connections
Be careful when you are crimping your BNCs to take care not to let any of the stranded wires of the shield touch the centre copper core of the cable, this is a common mistake resulting in a black screen. Check out our related tips for getting the best results.
Check your CAT5 connections
Using Baluns with CAT5 are a great way to avoid interference issues but double check the wiring of your colour coded pairs twice. Incorrect pairing at either end of the cable will cause problems and even loss of an image.
- Recommended Products
- BAL4KP - A 4K Passive 1 Ch Baluns (Pair).
Check around the site for other causes
Both cable and wirefree systems can be affected by factors that are beyond your control. Heavy duty machinery, lighting and other electronic devices too close to your cable run can all impact on the quality of your image and should be avoided using a different route. Wirefree signals can be severely impacted by simple things such as foil backed plasterboard that attenuates the transmission signal. Check out our DOs & DON’Ts of wirefree transmission for some handy tips here.
If all else fails, it may be that there is just some external influence on site that can't be fixed so make sure you always have a few Humbloc Ground Loop Isolators in your tool box. These handy little devices simply plug in to your video cable and can eradicate interference in seconds.
Download our printable PDF help file: How can I remove Earth loop interference from CCTV installations?