ellabbs 0 Posted April 14, 2013 I have a viola mbl4 dvr unit with 4 qvis cameras on... 3 of the cameras are fine but one keeps going faulty.... the screen goes black and fuzzy and sort of rolls... the camera is fine not even 6 month old.... if i mess about with the cable and power supply it comes up ok.... but i cant deduce its the cable or power...... ill put a still image of the problem on here.. ( i hope ) ive changed the power supply, and swapped it to cam 2/3/4 and its ok for a bit , then just slowly ends up like in the pic.. Share this post Link to post Share on other sites
ronp 0 Posted April 14, 2013 I don't understand what you mean by "if i mess about with the cable and power supply it comes up ok.... but i cant deduce its the cable or power......". It looks like it is a bad connection at the video cable, either at the cable's BNC connector or at the BNC connector on the camera. Share this post Link to post Share on other sites
ellabbs 0 Posted April 14, 2013 if i change the cables it comes up ok , ( ie ive disturbed the cables and sockets or whatever) then after a while a day ... a week..... it comes back.... is it better buying expensive cables.... i got a 30 meter cable from ebay at £10... its an intermittent problem im having.... Share this post Link to post Share on other sites
ronp 0 Posted April 14, 2013 Can you make the image go from good to bad by manipulating/disturbing one end or the other? Lifting, pressing, twisting? I think you're just going to have to work at it to isolate the problem. Sometimes it's difficult to tell exactly where the problem is as it could be where the cable goes into the connector, inside the connector, the connector's center pin's contact with the connector on the camera, even the camera's connector. Paying more $$ for a cable usually means better quality construction (up to a point) but this problem could be corrosion or even a faulty connector on the camera. Continuous pressure or tension on the cable end could cause a bad connection to form even in a quality cable. Share this post Link to post Share on other sites
bigglebowski 0 Posted April 14, 2013 It sure sounds like the cable. Premade cables usually are constructed with very poor or minimal shielding. Cable can come in a variety of shielding like quad, which will have 2 layers of foil and 2 layers of braiding. Typically there will just be one layer of foil and a percentage of braiding like "60-100%". Premade cables sometimes just have a layer of foil which can be easy to tear if the cable is put into a bind. So when you wiggle it you put it in a bind in another direction you are making the connection again and see good images. Of course bad connections could be in the connector as well from loose center or outer conductors. Cheap cable without significant shielding can be tough to reliably attach a new connector to. Share this post Link to post Share on other sites
