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any reason why not UTP?

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good day,

 

 

searching on the forums here and on NVT site i'm wondering more and more if there is a reason why not to use UTP cable with balun instead of coax?

 

also, do i need just 2 wires per camera? can a single cat5 cable transmit 4 cameras video?

 

thanks!

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1 cat5 can handle 4 video signals as long as you power at camera.

 

reason to use either? depends on you and your install plan. RG is good out to 200 - 250 ft. at best. Baluns/CAT5 can push video further.

 

Power/amp loss due to resistance in wire is an issue for both. 12vdc loss is higher than AC.

 

Video signal loss is an issue for both but Baluns are designed to "balance" out signal loss.

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Maybe STP would be better as it's shieled?

No. The capacitance losses are greater with shielded. Also, a lot of STP is not 100 ohms. That impedance is relatively critical for twisted pair to work properly with baluns.

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UTP is pretty versatile - you can run up to four cameras over a single cable; you can run one camera with video, power and control (serial); you can run VGA using VGA baluns; you can run KVM with the appropriate extenders; and of course, it gives you the future ability to easily upgrade to IP cameras.

 

The only REAL drawback is cost - the cable itself will cost about the same as coax with a power run (18/2 or station wire), but the baluns add a fair bit to the total price (around here, passive baluns start around $20-$25 each, meaning $40-$50 extra - or more - per camera). It helps balance out the cost if you can run four cameras on one cable, instead of needing four coax, but the cost savings will depend largely on the length of the run.

 

Sometimes the versatility can save your skin, too... like the site we did recently where the electricians put in a single 1" conduit... for us to run 9 camera feeds through. The ONLY way we could make it happen was to use UTP - one per camera, for video and power.

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Actually...coax has a lot longer distance transmission, doesn't it?

UTP only can last for 100 meters, which would be really short in outdoor cases.

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No. The 100 meter limit on UTP is for networks, not analog video. For video, RG-59 coax is typically good for up to 750ft. Passive-passive UTP can work at up to 1000ft; passive-active or active/passive UTP can work at up to 2000ft. and active/active UTP can go up to 4000ft.

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More to the point, the 100m UTP limit is for 10/100/1000 ethernet... other types of networks can go even further. We used to deal with a customer who used token-ring and had runs approaching 200m on Cat3!

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The real drawback is actually the bandwidth. 1Mhz = 80 lines of res

 

The high end ones are 5Mhz, or 400 lines of res. Think about that for a second. How many 540 line cameras are on UTP? Why?

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I had great experience using Cat-5 FTP cable - 2 pairs for 2 cameras 1 pair for audio and 1 pair for power.

 

If you turn one of the cameras off, you see slight interference from the other camera, but with both cameras on, the quality seems great.

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The real drawback is actually the bandwidth. 1Mhz = 80 lines of res

 

The high end ones are 5Mhz, or 400 lines of res. Think about that for a second. How many 540 line cameras are on UTP? Why?

Are you saying UTP can't handle the bandwidth? That would be a stretch since CAT-5 is rated to at least 100MHz and CAT-6 is rated to at least 250MHz.

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The real drawback is actually the bandwidth. 1Mhz = 80 lines of res

 

The high end ones are 5Mhz, or 400 lines of res. Think about that for a second. How many 540 line cameras are on UTP? Why?

Are you saying UTP can't handle the bandwidth? That would be a stretch since CAT-5 is rated to at least 100MHz and CAT-6 is rated to at least 250MHz.

 

LOL, not the wire man, the baluns.

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We have 470, 480, 520 and 540 line cameras and can't see any difference in resolution between RG-59 and UTP.

 

Same here. Except we use FTP (foil shielded UTP) because we run cables close to power cables.

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We have 470, 480, 520 and 540 line cameras and can't see any difference in resolution between RG-59 and UTP.

 

Which looks better to you, typical television or cctv?

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We have 470, 480, 520 and 540 line cameras and can't see any difference in resolution between RG-59 and UTP.

 

Maybe you can measure the difference with VLC and some random USB adapter...

 

 

(I'll go sit quietly in the corner now...)

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We have 470, 480, 520 and 540 line cameras and can't see any difference in resolution between RG-59 and UTP.

 

Which looks better to you, typical television or cctv?

It depends. SDTV and CCTV can look about the same. But there are too many variables to make a fair judgement. OTA broadcast TV is bandwidth-limited to <4.5MHz, which is approximately 300 lines, so a good CCTV camera with proper lighting and a high-quality monitor can actually look better. HDTV is another animal.

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Exacty right Mr. Servtech.

 

My point that I'm gently starting to make is that most installations out there have hardly any difference in image quality between the 380's to 540's. (camera resolution) We so often look at just one spec in the market or maybe two that we forget about everything else. In most cases, standard defination television looks crisper, sharper, and has deeper colors than a cctv camera that is rated high at 540 lines. Standard res TV is actually broadcast at 330 lines of res but due to the processing that signal goes through it produces better image quality. Lines of res are not the whole picture in so many cases. It's the DA processor and back end of the camera that plays a tremendous role on the image quality. To make things worse, it seems that most everyone I talk with has a real hard time telling the difference between the resolutions. In fact, a number of years ago we did a side by side shootout of an OEM'd Panasonic chipset 380 line camera against a very well known 540 line full body camera. It was a blind test and just about everyone thought the 380 looked better, or was the 540 line camera. It's really a fun test and I'd encourage everyone on this board to try it out for themselves.

Which leads me into the baluns. If the good ones only support 400 lines of res, and we can't eye-ball it and see a difference, why do we spend the extra money on the 540 line cameras? I think the simple answer is marketing. We've been taught that lines of res and lux are what we need to look at when selecting a camera. It's pretty aparent to me that there is a lot more to this equation. What i've learned over the years is that nothing beats a side by side test. You really have to find a camera that does what you want it to do without breaking the bank, but that's a whole 'nuther thread.

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Our resolution standard has always been table games. With any analog camera we've tested we are not able to tell the suits of cards 100% but there are subtle differences. When we tested cameras in 2001 or 2002, the best we could do was about 40%. That was using claimed 470-480 line cameras.

 

By 2005 or 2006, with the advent of the Pixim chip, we were able to up that to maybe 50%; not a significant difference. Testing some of the newest cameras with stated 520-540 lines of resolution, we have been able to up that to around 70%.

 

330 to 380 line cameras approach 0%, as expected.

 

We're waiting on a Panasonic demo that claims 600 lines...

 

Of course, megapixel solves that problem but the ones we've tested have other issues - poor light sensitivity and low frame rates for two.

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I suggest you do not use UTP!!

 

That is exactly what my cabling contractor advise me against UTP. However I am still VERY keen to bring this stuff into my country.. a passive balun that transmit both power and video signal over 1 UTP ..

 

I've personally tested the baluns .. did not to the extreme but here are the results:

 

For both power and video, perfect at 65m (abt 200ft)

For video only 200m (abt 670ft)

 

And that is using some very cheap UTP cables.

 

This is my personal feel abt the UTP/baluns setup

 

Pro:

1) Cheaper - 1 UTP + 1 pair of balun (abt $12 for the samples I bought)

2) Future conversion - can be convert to IP Cams in the future with POE

3) Easier to lay - we all know how inflexible coax are .. Crimping a RJ45 is so much easier than doing the terminations for both Coax and power

 

Cons:

1) More pts of failure .. the fault could be from

- UPT

- RJ45 connector

- balun

2) Less revenue for cabling contractor - He cannot charge the full cost of laying the UTP for future conversion.

 

Just my 2 cents .. like to hear from the rest of forumers

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We're waiting on a Panasonic demo that claims 600 lines...

 

 

Don't really need wait .. 2 Korean companies have already done it ..

 

Samsung Techwin has 1 model but not available in country yet .. can't remember the model .. but u can chk out their website .. it is a box camera

 

 

CNB Techonology has a range in their Mona Lisa Series. Tried to contact them but they seemed very protective in releasing any information though ..

 

Unfortunately I am too new to post their URLs .. in this post .. but I am sure u can google them ..

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wow, quite lot of information on this one for me

 

we just started to test nvt product

as for quality, as long the client is okay, we dont mind as well

the main concern will be troubleshooting if something wrong latter on

 

anyone has experience using balun etc2 to convert this

do they broke easily or causing some issue ?

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