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Double image problem. Need helped on this

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Dear All,

 

I need help on this. I just installed 2 * 16 channel Kodicom DVR (embedded KSR series) total of 32 cameras (Panasonic dome camera). We did a spot out from Location A where the DVRs are located, running about 180M of Belden RG59 cable (solid strand)

to Location B (there is 6 extra cable spare RG59 cable from location A to Location B)

 

At location B, we connect the BNC to 2 LCD monitor. The image appear but show double image on both the LCD montiors. I try a number of solutions but no avail

 

1) change to LCD TV

2) Adding of 2 video amplifier and the EOL of the cable

3) Changing different RG59 cable

4) parallel 2 RG59 per signal cable to increase the cable strand

5) Using the same camera and same DVR, I brought a a roll of RG59 cable of 200M and connect to the DVR and camera, it work no problem

6) moving the 2 LCD apart

 

Nothing seem to works. I am at my wits end on how to solve this problem. Can anyone here offer any advice on this problem. Alternatively can anyone teach me how to test the RG59 cable

 

I do have a mulitmeter, what else do I need to purchase to test the cable strength, ohms value(how to test) etc

 

I read up on this on the internet, it just tell me double image is usally termination problem, but it does not tell me how to solve the problem. Please help?

 

 

Thanks in advance

 

Kelvin

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you might try a CAT5e cable with a signal booster... of course use active/passive baluns to convert to BNC.

 

I didnt think you could actually run the far on a coax cable, hooked up to just a monitor.

 

dont forget, when you go from the camera to the LCD, the camera is powered. when you run from a DVR to an LCD... there is no power source.

 

let us know!

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Are you running the monitors in parallel; perhaps using "Y" adapters or "splitters" like this?:

120627_1.jpg

 

If so, that is the cause of your double image. If the monitors don't have "looping" inputs, get yourself a distribution amp to actively split the signal.

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HI,

 

Thanks for the reply, here is some of the things I try

 

1) I run the same 200 M of coxial cable at location A and plug it directly from the DVR to the LCD montior, as it work ( I presumed that the cable length is no longer the issue, or am i wrong?)

 

2) Location A is a server room where the DVR is housed, where location B is Management office with the viewing is done, so both place have power source in the location. The cameras run inside the whote building.

 

3) I did not use any splitter as Location A have 2 * 16 ch DVR each running thier own RG59 cables to location B connected to 2 different LCD monitors (eg DVR A to LCD A and DVR B to LCD B)

 

Any more suggestion is appreciated

 

Regards

 

KT

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any chance of a pic?

 

have you put the screen directly on the end of the camera to rule out that its a faulty camera not cable ???

is it an exact double image? could possibly be be leakage ie signal from one camera cable radiating into the other.

 

sometimes cables can get a fault where braid finishes/restarts overlapping inside the cable. gets a bad connection and do a few strange things. a simple test with muiti meter should tell you if cable is faulty.

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Dear Tweake,

 

Actually, all the 2 * 16 camera on the 2 LCD screen are having

double image. I try to get a pictures for that and upload there.

How do I exactly test the cables? Pretty Noob here

 

Regards

 

KT

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Dear Tweake,

 

Actually, all the 2 * 16 camera on the 2 LCD screen are having

double image. I try to get a pictures for that and upload there.

How do I exactly test the cables? Pretty Noob here

 

Regards

 

KT

 

Good quality RG59 would give a a good picture up to 270m before you start to lose the fine detail in the picture.

 

I would suggest that you take the monitors back to the server room and connect direct to the DVRs with a pre-made bnc-bnc lead.

 

I would guess that you will still have the double image.

 

See if you can get hold of a CRT CCTV monitor (as a CCTV engineer you should always have access to one) or if not try a different monitor.

 

If you still have the problem, post the model number of the LCD monitor used so that we can check this out.

 

Ilkie

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You can perform some very basic tests with a multimeter, mostly just for shorts and continuity, but nothing that will tell you the quality of the cable or whether there's noise on it.

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Dear All,

 

My problem is still not solve yet, today we went down and installed DVD player using the same cable and same LCD monitor

The picture came out perfect without any problem, I would presume that the cables are working fine and is able to support the 200 M length. Now what is the probable problem?

 

Grounding ? The only suspicion I have is that the DVD is a 2 pin plug without ground while my DVR is a 3 pin plug with gnd. Could that be the problem? My 32 cameras is installed all over the place, each is powered by a different 230V power 3 pin plug running at 24 Vac (tube camera)or 12 DC (dome camera).

 

Any advise again

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