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Slight Distortion in Video Feed

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I suspect moving the Cat5 away from the 480V will make a BIG difference, even if you just move it by a foot or two.

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Yeah first I would try another camera just as a temporary test.

If that has the same issue, then as mentioned get it away from the high voltage. Should not have been run that close to it anyway.

If still an issue, then try some different passive baluns or try active to passive or if you want to go all out active to active, but something from a decent brand - remember you get what you pay for. You are right though 300' should be fine but I was talking 700', although I even had issues before with a couple baluns at 200', probably was just a crappy brand though, wasnt lines though, lines occur without the balun ofcourse!

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Just looking at your pictures... is the video Cat5 actually strapped TO the 480V conduit, or just close to it... and if the latter, HOW close? How far does it parallel the 480V for?

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Just looking at your pictures... is the video Cat5 actually strapped TO the 480V conduit, or just close to it... and if the latter, HOW close? How far does it parallel the 480V for?

 

Soundy, you are on it my friend ! I had a guy out working with me on this project and from what I could tell, he strapped the CAT5 directly to the conduit. I would say it runs for about 30 to 40ft before it branches off.

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Ugh... give the n00b a smack upside the head!

 

Quick test: snip all the zaps strapping the cable to the conduit... this should allow it to sag away from the 480V line. See if that doesn't clear up the problem right there. Then you can go back and either re-route it along some lower-voltage (120V) stuff, or to the girders, or use some cable saddles or something to attach it right to the bottom of the Q-deck, away from the 480V.

 

134046_1.jpg

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Ok guys...here's what's going on..

 

Moved the CAT5 line away from the high power conduit .. Still with the distortion.

 

Tried to install video isolators in the line...This worked a little bit but I'm still having the issues.

 

I was not able to pick up the active baluns. I'm probably going to order some today to see if they will fix the problem but I'm still having this weird issues..

 

If I plug 3 of the cameras into the video balun, the video is ok to an extent..whenever I plug the 4th camera in, the video goes to crap on two of the other cameras. I check to see if the line was crossed anywhere and also checked the connections and everything is fine. The camera in question shows up fine whenever I plug it into my field test monitor...

 

I am out of ideas and I don't know what the Issue could be....Anyone ?

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Ok guys...here's what's going on..

 

Moved the CAT5 line away from the high power conduit .. Still with the distortion.

 

Tried to install video isolators in the line...This worked a little bit but I'm still having the issues.

 

I was not able to pick up the active baluns. I'm probably going to order some today to see if they will fix the problem but I'm still having this weird issues..

 

If I plug 3 of the cameras into the video balun, the video is ok to an extent..whenever I plug the 4th camera in, the video goes to crap on two of the other cameras. I check to see if the line was crossed anywhere and also checked the connections and everything is fine. The camera in question shows up fine whenever I plug it into my field test monitor...

 

I am out of ideas and I don't know what the Issue could be....Anyone ?

 

 

how is the cat 5 connected to the balun. the 4 way ???

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The cat5 is connoted to the video baluns by a RJ45 connector. There is also a place to directly connect the wires into it using push down blocks and I have used both and the problem still persists.

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Wait so you arent using baluns, you are using a multi output cat5 receiver and transmitter?

also before changing that I would test another totally different camera first.

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Wait so you arent using baluns, you are using a multi output cat5 receiver and transmitter?

also before changing that I would test another totally different camera first.

 

Yes, we are using the baluns for the video feed on all of the cameras.

 

1x single video balun at camera side

1x single video balun at dvr side

1x 4port video balun at camera side

1x 4port video balun at dvr side

 

 

I will see if I can get another camera out to test in in the next few days.

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Wait so you arent using baluns, you are using a multi output cat5 receiver and transmitter?

Sounds more to me like it's a simple four-baluns-in-one-box type unit. Perhaps the OP could give us the exact make and model of the unit.

 

I might suspect incorrect wiring in the RJ45 (straight-through layout rather than T568-A or B), but that wouldn't account for the problem persisting when using the punchdown terminals.

 

This problem STILL sounds to me like a ground-loop issue - the interference changing with the addition or subtraction of cameras just screams it. If the BNCs on the balun are all common-ground, that could be part of the issue, with each pair in the Cat5 run being a different length.

 

One thing that might be worth trying would be to use four separate baluns *at one end first* - use screw-terminal or tool-less types, snip the RJ45 off, splay out the pairs, and put one pair on each balun. If that helps, but doesn't eliminate the issue, then try four baluns at the other end.

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Wait so you arent using baluns, you are using a multi output cat5 receiver and transmitter?

Sounds more to me like it's a simple four-baluns-in-one-box type unit. Perhaps the OP could give us the exact make and model of the unit.

 

 

http://www.cctvoutlet.com/All_Surveillance_and_Security_Products/video-baluns/video-balun-B45X4.html

 

I liked the idea of using seperate baluns on the outside connections. I am going to try this before I order the active baluns. And yes I know roy....I am going to try a different camera also. I sent the scissor lift back today so I am going to have to figure out a way to get back up these light poles to change that camera

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oh boy .. eclipse baluns .. do they EVER work?

all ive seen from them on other's jobs are problems.

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Can't say I've ever used Eclipse... ADI/Burtek here carries GVI, GEM, National Electronics, and MuxLab... haven't had any problems with any of them. I like the GVI and GEM tool-less models, personally.

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granted most of the problems ive seen with the eclipse baluns are the techs ran passive baluns too far, in other words they listened to the marketing hype and believed the specified distances

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granted most of the problems ive seen with the eclipse baluns are the techs ran passive baluns too far, in other words they listened to the marketing hype and believed the specified distances

 

Well distances only max 400'ft ...well under the marked distance, but I don't see how that would affect the video feed when if each camera is connected individual using the same baluns, gets the signal at the dvr perfectly.

 

No crosses in the lines..

Used the single balun on camera side and it cleared up the problem a little bit

 

The only thing that seems to be working, is using multiple line isolators at the DVR side for each camera. I have at least 4 line isolators on one of the cameras right now and the picture has looked the best it has since i started the install.

 

So my conclusion is that It is a line noise issue but from where I the thing that i can't figure out. Has anyone used a setup like this with the DVR in a IT cabinet? Could i be getting interference from all of the IT equipment? Maybe I should have used a shielded CAT5 cable instead? I appreciated the suggestions and comments guys, I really don't have anyone else to bounce ideas and thoughts off of so this forum is very helpful in that respect.

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Okay, they're filters, not isolators... so grounding could still be an issue... I just can't think of where it might be. Active baluns next???

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Okay, they're filters, not isolators... so grounding could still be an issue... I just can't think of where it might be. Active baluns next???

 

Probably...thats what I'm thinking..I'm just going to let the customer know what's going on and I'll deal with it. I just hope that that's the problem because I really can't think of anything else....

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change the camera.

power the camera locally at the camera with a plug in power supply.

make sure the camera is going straight back to the DVR with single connectors, no other cameras connected, also cable at least 1-2 foot away from high voltage (120v) and in this case, away from ANY other cable. Get some ground loop isolation (these come with it built in, NVT.com - not cheap though)

 

EG. I recently had a camera, short run, PSU is isolated, good RG59 siamese - lines started at night time only, and not every night. Turns out the camera was just a half inch underneath a bunch of cable which had been added to over the years, maybe some cable for the gate controller or even high voltage, anyway moved the camera down 1 foot and no more lines.

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Just to let you guys know, the problem was never resolved. The closet I could get to a perfect picture was using the In-line signal isolators.

 

I'm going to chalk up the distortion to the length of the CAT5 run. If I ever try this again, I would probably use a shielded CAT5 wire and I don't think I will try to run more than 1 signal through a single CAT5 cable.

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