Bsw 0 Posted March 11, 2009 Hi all, I've got a problem and was hoping to pick your brains. I resently installed a new cctv system. Which consits of a DVR and four cameras(2x basic,2x with audio), everything was working great until i tested the audio. Theres a loud .....buzzing/static sound. The mics seem to work, I can still hear people talking etc, just has the buzzing over the top. So i went around checking everything, all the connections,cables,etc there all fine. Next i looked around for somthing that could be creating interference . Near one of the cameras (about 3 meters away) theres a fridge. Ok so that could cause it for the first cam but the second theres nothing and I mean nothing. This has got me pretty stumped. If it was one cam i'd say its faulty and get a replacement,but two.. The DVR has four audio inputs i've tryed all of them. no change. The buzzing is there when Live & Playback(both TV screen and networked to a computer). The only thing i can think it might be is a bad DVR, but i rather not send it back and get a replacement since that could take a while and I need these cams to stay open(by law). Is there a know problem with Xvision VIS200D cams? Any help would be great. Share this post Link to post Share on other sites
scorpion 0 Posted March 11, 2009 There are so many issues that you need to trouble shoot. You will need to describe more about the install. What kind of microphones do you have www dot microphone dot com ??? What kind of wiring are you using to transfer the audio from the mic to the DVR? What kind of power supply are you using on the Microphones. If you are using AC on a DC mike then this may be an issue You need to use a copper center conductor, and a copper shield coax to send audio. microphones need a preamplifier. I assume you have a "security level" microphone, and the preamplifier is allready built in. If the wiring that came with your microphone has a ground wire then it only needs to be connected at one end. This is sometimes referred as a "drain". If it is "grounded" at both ends then it can give you problems. The input of the DVR needs a one volt to one volt peak to peak line level signal. This is the same as the audio that would come out of the red, and white RCA audio equipment such as VCRs, and DVD players. I know you know what you are doing, but I put all this info for those who read this post that are not familiar with this info. What kind of a system do you have set up? Share this post Link to post Share on other sites
Bsw 0 Posted March 14, 2009 Sorry for taking so long to reply, been really busy. Thanks for helping. I know you know what you are doing, but I put all this info for those who read this post that are not familiar with this info. I know nothing compared to what you guy do. But I'm a quick learner OK. My setup is really simple but it does the job. well apart from the audio. The site i got the equipment off is www y3k com (I'm a new user so no URLs) DVR: Xvision H4DVR www y3k com/section.php?xSec=59&jssCart=434b3c7c358db164c66449b59a750d5b " 4 Camera (4 Audio) Real Time H264 Pentaplex " Cameras i'm having the problem with: Xvision VIS200D www y3k com/section.php?xSec=5&jssCart=434b3c7c358db164c66449b59a750d5b X 2 Second down, there sites just been updated and is messing around, so i can't link to it own page. The cables are the ones that came with it, that includes the power. There 40m composite cables.(Yellow = video, White = audio, Red = power) The cameras and DVR need adapters to convert the video cable to co-axial. The audio doesn't need adapters.(composite all the way though) Power is whatever came with it. not sure if its AC or DC, will have to check tomorrow. All together i have 4 cameras connected, the two that work perfectly are 1x basic Dome(No audio),1x Night Vision Bullet Cam(No audio).Can link if you need it. I was hoping that keeping it simple and all "pre made" would avoid any problems. I was wrong instead it's created a system that seems hard to debug. I'm moving the whole system around tomorrow so I'll check everything again. Anything I need to keep a look out for? Share this post Link to post Share on other sites
scorpion 0 Posted March 15, 2009 I do not see any red flags that stands out, unless you are running a real long distance. With what you describe wiring wise I do not understand why you are having issues. I am not familiar with those devices, and I do not know if that may be your issue. My battery operated monitor has an audio input so I can test at the camera's audio output, and I can test at the DVR input, and the DVR audio output. Perhaps you have a small portable TV that you can set up at the camera with an extension cord to see if it is putting out audio. What do you think? Share this post Link to post Share on other sites
Bsw 0 Posted March 16, 2009 Hmm, good idea. I'll try setting up a TV near one of the cameras. Well Thanks for all the help, I'll go around testing as much as I can, If I find out what's causing it I'll let you know. If not I guess its two new cameras. Share this post Link to post Share on other sites
