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srtdodge05

Signal issue over coax

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I have 3 Analog camera's running on RG6 direct burial cable. The run is around 1,200ft from between buildings. During the day the picture on the camera's aren't bad but it is a little wavy in some areas. At night The picture is real bad or sometimes I get nothing at all. Camera's are on a 12v system. I bought some speco ground loop isolators to see if that fixed my problem. With the filters the camera's wont work in the day time but they will at night. So that has caused another problem.

 

So I'm wondering if there is somehow I can boost the signal over the long run to see if that fixes the problem?

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Questions:

 

Local Power 12v or is it Siamese RG6 back to head end?

How far is power supply to the camera?

What gauge cable?

Do the cameras have IR?

 

Break out the ohm meter and measure the coax against ground on both buildings. I bet they are different.

Going between buildings may require a common ground. If cameras are getting ground from power supply in building B but the DVR is in Building A you may experience what you are seeing right now. The night time /day time issue appears to be voltage draw hence asking about IRs. I would run a lightning arrestor in both buildings and ground to a common earth ground. At 1200ft I assume you have splices already. You could try a amp/booster approx $22/ea or 4ch unit approx $60.

 

I also would recommend using 24vac cameras as the 12VDC are considered "Amateur" cameras and more suited to residential and very small installs.

 

Another item to check is the connectors. Do NOT use screw on type connectors as they are common for a stray shield cable touching the center conductor. Crimp or compression are recommended. Odds are if you are experiencing the same issue with all remote cameras it is related to grounding.

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RG6 from the Building with DVR to the Building with Camera's. The power supply is in the same building as the camera's. The camera's are no more then 10ft from the power supply. The Coax is under ground and in water. The building with the DVR supplies all the power to the building that has the cameras on it. I even ran the power supply for the camera's off a UPS battery unit not using the building power. This is the only building I'm having trouble with and it is also the longest runs I have.

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srtdodge,

around 1200 ft, most of analog signals from camera get severely distorted. Most of analog video decoder in the DVR card fail to capture the incoming video signals. Amplifying signals without channel equalizing feature, would not solve the problem.

There is only one video decoder solution for this. I can not name it.

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IF you don't have testing equipment then try an inline amplifier that I recommended in previous post. If you have a 24vac camera you could try, I would do that first before ordering. 1 other possibility is try a larger power supply 2A or greater. I know it is a short run but try it. Sometimes the ratings are not accurate. Let me know which one works for you.

Cheers

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srtdodge,

around 1200 ft, most of analog signals from camera get severely distorted. Most of analog video decoder in the DVR card fail to capture the incoming video signals. Amplifying signals without channel equalizing feature, would not solve the problem.

There is only one video decoder solution for this. I can not name it.

 

I agree, I would suggest a launch amp and a video line equaliser, opto-isolated if earth differential is a problem.

 

Try http://www.addlestone-electronics.co.uk/

 

It would be useful if you had some test equipment to set up the circuits.

 

Ilkie

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