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CAT5 vs separate coxial/power cables? Hows' the video?

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Has anyone done tests on using cat5 (with baluns) as a replacement for RG59 regarding video frequency response rolloff?? IOWs', what does the video look like using cat5 vs coax after a couple of hundred feet? It just seems using a twisted pair with two matching xformers HAS to affect the video quality.

 

Next, can I assume only one of the pairs of the cat5 is used for video? Can I also assume another pair could/would be used for power?

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Never done any real testing as I avoid Cat5 and baluns with the expection of a few circumstances. As such I never ran coax next to it to find out.

 

You can run 4 video feeds through Cat5.

 

You can run 2 video and power for 2 bullets/boxes up Cat5, very low power those wires are tiny.

 

I ALWAYS run 18-2 with the Cat5 just for power.

 

 

I don't use Cat5 unless the run is more then 250' feet, usually longer.

 

I might use Cat5 where you have a cluster of cameras in the same area. I'll run the Cat5 into the area and coax>cam from it x4.

 

Example large retail warehouse...

Cat5 to the front door area, 4 cams there covering the entrances and exists from both inside and outside.

 

Cat5 all the way to the back at the loading dock, 1 cam inside the dock, one outside the foot door, and another looking from the outside at the dock.

 

Coax to 4 PTZs up the middle of the building, Cat5 for the RS485 data.

 

Coax for everthing else.

 

 

 

Cat5 is nice for building to building like in schools, 1 Cat5 to each building and you can hang 4 cams off that building.

 

Whenever you do building>building USE LOCAL POWER!!! The buildings will have a difference in grounding and you will see that in your video.

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Bruce,

Answer to your question lies in the differences between the manufacturors. Some big ones like NVT deliver outstanding results, while other brands just seem not able to deliver a decent balanced signal over UTP.

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Yes I have tested CAT5/Baluns against RG-59 siamese. I used the CM2 to record results. Bottom line was that passive baluns had a dramatic drop in all camera level outputs. Further the CAT5 the worse it got. The picture displayed fuzy dull pics and the overall TVL on screen diminished also with distances. But, for some odd reason the baluns keep on working. Pics lost the depth & tvl.

 

I also use a mixture of passive with active. Basically the active was on the DVR side. Camera signal(s) held and I was able to adjust for different lengths of CAT5.

 

If you looked up a camera signal output(s) required for a high quality video signal then used a meter to define your system you'd toss the passive balun's in the garbage based on signal loss. Passive baluns get away with passing the signal becasue they still put out a picture.

 

I actually saved snapshots of both for record. The pics were obvious. Only thing that changed was the cabling, same camera's, DVR, ect. And I recorded the readings on a scrap of paper somewhere lost on my desk here?

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I also use a mixture of passive with active. Basically the active was on the DVR side. Camera signal(s) held and I was able to adjust for different lengths of CAT5.

 

I do it backwards, active transmit and passive recieve. My logic is getting the signal to the DVR won't amplify issue picked up along the way.

 

Like I said though, very rare for me to use Cat5.

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Ballpark price range (US) for active baluns?

 

Anyone disagree with any of the above?

In our fairly large system (more than 900 cameras), we started with RG-59 in 1999 and started pulling CAT-5 in 2003. We use cheap ($30) passive baluns at both ends for runs that are less than about 500 ft. and have had few problems.

 

Oscilloscope tests of passive baluns vs. RG-59 do give the nod to RG-59 but eyeballing the picture, both live through the 9760 Matrix and played back on our DVR system, shows no perceivable difference. The resolution of our table games fixed cameras is virtually identical and video noise is no better or worse on either.

 

One possible difference could be the way we set up cameras. We aim and focus and adjust iris settings via radio at the main monitors rather than in the field. That could compensate for any differences in video levels.

 

We also use CM9760-MDA's on each input so that could have some effect.

 

As far as active vs. passive, we have found that there are also no perceivable differences for shorter runs (less than 500-600 ft.). On longer runs, we have not been very happy with the Vigitron Vi6016. We are replacing ours with the Pelco active receivers with Adaptive Technology.

 

Don't believe the NVT hype about how their product is superior to other brands. We have tested both side-by-side and for all intents and purposes, there are no differences except price.

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By the way, we have had a number of problems with CAT-3; both in existing runs and where we pulled separate new cable. We had to use CAT-3 for a 1,500 ft. run that required Direct Burial cable due to questionable conduit. Direct Burial CAT-5 is very expensive and hard to find.

 

All of the CAT-3-rated Direct Burial cable that we found has almost no twist in each pair. That appears to have a major effect on the signal-to-noise ratio.

 

We have also experienced the same kinds of ground loop issues with twisted-pair as with coax since baluns do not isolate the grounds. Even the Vigitron active receiver hub is not immune. We are hoping Pelco's active receivers have less noise issues and ground loop sensitivity.

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Why would anyone use CAT-3 anymore? There is very little difference in price between 3 & 5 (at least in the US) and 3 isn't any good for data lines anyway.

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rg59 250ft max. beyond that CAT5.

 

CAT5 under 500ft. with little or no difference in video? That's very good since my tests with CAT5/passiveB's had a huge drop in all video signals and you could view the loss of resolutuion and see the sides of the screen drop off the pic as the distance increased.........almost as if the bandwidth was not good enough for color......

 

Like I stated, it works.............not to any standard, just that video is transmitted and received. Active is another ball game, especially when you mix with passive as the results are different with each manufactures balun.

 

I guess the bottom line is pretty much the same as with everything else in CCTV. Specs are sometimes, manytimes, written but not backed up.

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Why would anyone use CAT-3 anymore? There is very little difference in price between 3 & 5 (at least in the US) and 3 isn't any good for data lines anyway.

1. Because it is already in place for Telco equipment.

2. Because it is difficult, if not impossible, to find direct-burial CAT-5, especially in 25 pair or more.

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CAT5 under 500ft. with little or no difference in video? That's very good since my tests with CAT5/passiveB's had a huge drop in all video signals and you could view the loss of resolutuion and see the sides of the screen drop off the pic as the distance increased.........almost as if the bandwidth was not good enough for color......

We have been using TP with passive baluns side-by-side with coax for 4(+) years without noticing any of the losses you describe. I don't know what your experiments showed but I could show you two cameras on adjacent gaming tables; one using coax and one using CAT-5 with baluns (GVI VB-59 and/or Vigitron VB1001M) and I'd be willing to bet you could not tell the difference.

 

And literally every visitor to our department compliments us on the PQ of our table game cameras.

Edited by Guest

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keep in mind that my baluns were not the very best....and your results are dang good from where I sit....no joke. I just stay away from baluns unless I have to use them......but your making me rethink that using better baluns.

 

do ytou find cat5 or cat6 better for baluns? bandwidth?

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Mostly we use CAT-5e. It depends on what we can get. We use 25 pr. trunks with 66 punchdown blocks at each end of the trunk and 4 pr. at each end from there. We plan to start following ethernet standards in future construction (100 meter limits and better patching methods) to accomodate future IP cameras.

 

Perhaps the difference is due to our choice of cameras. A lot of our newest cameras have baluns built in. We are using the Ganz ZCD-3000 series in many areas but also using Pelco CCC series and Ikegami standard cameras with external baluns and Pelco Spectra 2, 3 and 4 in both flavors (with/without NVT baluns built in), depending on when they were purchased.

 

We also use Pelco CM9760-MDA's on all inputs. Their buffering capabilities could also explain the difference.

 

In some of our newest installs, we have started using the West Penn siamese cable that has 2 CAT-5 pairs with 18/2 or 16/2 power at the camera end. We locate our punchdown blocks next to the power supplies so it is easy to split the siamese cable at that end.

 

The GVI and Vigitron baluns are not expensive. We get them for under $30 each.

Edited by Guest

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From what we tested last time on a 300m Coaxial and 300m Active Balun.

 

W/o comparing side by side, you can't tell the difference between coaxial and cat 5.

If you put them side by side and compare, coaxial seems to have better images.

 

Normally, we use coaxial for all installation. Balun only use when distance is great. 1 x Cat 5 can put 4 cameras. We are also exploring channel multiplexer/demultiplexer at the moment. Can use 1 coaxial cable to send mutiple video channels. Great if you are adding cameras in places already wired up with coaxial. Cut down on the amount of cabling.

 

My conclusion ? Small installation, don't bother with balun. Only for very long distance installatoin then consider them.

As i always think, the more piece of electronic equipment you put into the equation, the higher the chances one of them break down.

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