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naiefelyemeni

hello everyone.. need help looking very stupid at the job

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ok, i installed 32 cameras on 2 16ch AHD dvrs using cat5 and using baluns on each ends , and using 2 16ch power supply boxes.. used 1 twisted pair for neg power and 1 pair for postitive and 1 pair for video pos and 1 pair for neg video.. turned on everything and only got like 5 cameras lol and they were all garbled picture.. so i took out all the power cables from the box and did one by one , now i got 10 cameras working but seems like theres horizontal lines and a little shaking.. if i touch some of the cables that are behind the dvr many cameras get worse or better? and 3 of those cameras are on a seperate 2amp power supply, because if i put one of them back to the box all the cameras go crazy?? and some cameras as soon as i touch the postitive, the camera turns on? without the negative? wierd issues.. i think theres a negative/ground issues? i checked all the cables from both ends and all are good? Also is it true it maybe im using a pair for each connection of power when 1 wire should be used? im confused and going crazy

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Big mistake to use CCA cable. I would pull it out. But you may be able to salvage it with better baluns...Ill leave it to the guys use these baluns to make a recommendation. There are special baluns made for AHD systems. Like these

http://www.cctvcamerapros.com/AHD-HDTVI-HDCVI-CCTV-Video-Balun-p/vb-hd2.htm

Dont know if those are any good though...hopefully someone can help you out.

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i dont care about the cable its all the labor! it took over 20 hours to run those cables how about these baluns ?

 

http://www.ebay.com/itm/321842064983?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

 

 

i already ordered these earlier today they say they work graet with ahd sytems?

 

http://www.ebay.com/itm/151649624874?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

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Also what about that weird problem when you just touch one cable to the box's terminal l i believe it was a positive and the camera turns on?? without connecting the negative??! or vice versa.. just one cable turns on the camera??

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i dont care about the cable its all the labor! it took over 20 hours to run those cables how about these baluns ?

 

http://www.ebay.com/itm/321842064983?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

 

 

 

i already ordered these earlier today they say they work graet with ahd sytems?

 

http://www.ebay.com/itm/151649624874?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Dont buy anything off ebay....buy from a reputable dealer...buying on ebay is what got you into this mess in the first place.

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You may use "cat5" for AHD cameras, but RG59 cable recommended. Why baluns? I do not like to put Baluns at both ends. Why at the camera's end?

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ok i have ground loop on some cameras, the exterior wall of the store has stucko and sheet metal, you think this will cause the ground loop? and why is it when i only touch one of the power ends to the power box the camera turns on??

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You may use "cat5" for AHD cameras, but RG59 cable recommended. Why baluns? I do not like to put Baluns at both ends. Why at the camera's end?

 

 

so i dont need them at the cameras end? i thought i need them on both ends to balance the line? and how would i connect it tot the camera end anyways? since i used cat5? unless i can use this at teh camera end?

 

http://www.ebay.com/itm/New-50-PCS-Coax-CAT5-To-Camera-CCTV-BNC-Video-Balun-Connector-For-CCTV-Camera-/331151630776?hash=item4d1a2ce1b8

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Hello naiefelyemeni.

I suspect part of your problem is that you've used

1 pair for video pos and 1 pair for neg video
To use twisted-pair for video, the video must travel through only one twisted-pair. So connect video pos to one wire, and neg to the other. The remaining twisted pair is unused (or you can use the wires for power as well). Use a balun at each end (camera and DVR).

This might fix your video problems.

 

You might be able to use copper-clad aluminium for short distances. At least it's not as horrible as copper-clad steel. Full copper is best for CCTV.

 

The camera works without the negative power terminal connected because the camera designer has done a bit of a cheapy, and hasn't used an isolated power supply. The power supply negative is connected to the coax shield inside the camera.

Basically you have a ground loop, which could mess up your images. Since you have a spare twisted-pair, you could try using this pair as an extra negative (ground) for the power supply. This might help stop some of the power supply current from travelling through the video twisted pair.

 

So your cable would have:

one pair for video

one pair for power positive

two pairs for power negative.

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So your cable would have:

one pair for video

one pair for power positive

two pairs for power negative.

I would split 3 pair evenly

3 wires for ( + )

3 wires for ( - )

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You may use "cat5" for AHD cameras, but RG59 cable recommended. Why baluns? I do not like to put Baluns at both ends. Why at the camera's end?

 

 

You need baluns at both ends ..... If you don't understand baluns then start another post to talk about them

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Your first problem is how you have wired up your system

 

Your biggest problem at the moment is how you have connected your baluns ..... Pair for video + and pair for - ..... This need to be changed before anything else .... You should ONLY use 1 pair IE blue for video + blue white -

 

Rest of pairs look at ak post

 

This needs doing to see if you do have problems

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You may use "cat5" for AHD cameras, but RG59 cable recommended. Why baluns? I do not like to put Baluns at both ends. Why at the camera's end?

 

 

so i dont need them at the cameras end? i thought i need them on both ends to balance the line? and how would i connect it tot the camera end anyways? since i used cat5? unless i can use this at teh camera end?

 

You DO need them at the cameras end. As they have already told you, use only one pair for video.

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Hello naiefelyemeni.

I suspect part of your problem is that you've used

1 pair for video pos and 1 pair for neg video
To use twisted-pair for video, the video must travel through only one twisted-pair. So connect video pos to one wire, and neg to the other. The remaining twisted pair is unused (or you can use the wires for power as well). Use a balun at each end (camera and DVR).

This might fix your video problems.

 

You might be able to use copper-clad aluminium for short distances. At least it's not as horrible as copper-clad steel. Full copper is best for CCTV.

 

The camera works without the negative power terminal connected because the camera designer has done a bit of a cheapy, and hasn't used an isolated power supply. The power supply negative is connected to the coax shield inside the camera.

Basically you have a ground loop, which could mess up your images. Since you have a spare twisted-pair, you could try using this pair as an extra negative (ground) for the power supply. This might help stop some of the power supply current from travelling through the video twisted pair.

 

So your cable would have:

one pair for video

one pair for power positive

two pairs for power negative.

 

 

 

Makes sense, your making me feel a whole lot better today, cant wait to go back and try that out! thanks!

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Your first problem is how you have wired up your system

 

Your biggest problem at the moment is how you have connected your baluns ..... Pair for video + and pair for - ..... This need to be changed before anything else .... You should ONLY use 1 pair IE blue for video + blue white -

 

Rest of pairs look at ak post

 

This needs doing to see if you do have problems

 

 

will do, its my first install with cat5 , now i learned something.. thanks

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