Patzfan 0 Posted April 15, 2015 Using Dahua 2.4mp HDCVI system, cat5e Outdoor cable, getting rolling bar and distortion on longest run. Do ground loops work on CVI systems? what are the best baluns to use for 1080p Share this post Link to post Share on other sites
Numb-nuts 1 Posted April 17, 2015 For CVI you can use a good quality standard passive balun as used in analogue CCTV. (IN THEORY) I haven't done it myself yet, but that is what my information is Share this post Link to post Share on other sites
Securame 0 Posted April 18, 2015 (edited) You can. I have actually seen baluns specific for HDCVI, I did try them too, but I did not appreciate any difference from a good analog balun. Edited April 19, 2015 by Guest Share this post Link to post Share on other sites
the toss 0 Posted April 19, 2015 I think you need to keep in mind just what baluns are. They are simply an impedance matching transformer - nothing more nothing less. The better ones have a small amount of filtering built in but unless that is an issue then it would come down to manufacturing quality. There is nothing mystical about HDCVI. Share this post Link to post Share on other sites
ak357 0 Posted April 19, 2015 I think you need to keep in mind just what baluns are. They are simply an impedance matching transformer - nothing more nothing less. The better ones have a small amount of filtering built in but unless that is an issue then it would come down to manufacturing quality. There is nothing mystical about HDCVI. Toss do u have some tech info about HDCVI ? Share this post Link to post Share on other sites
the toss 0 Posted April 19, 2015 I've been digging for a while with not much results but I'll give you the bits Ive got. Basically HDcvi , HDtvi & Ahd are transmission techniques based on Quadrature Amplitude Modulation (QAM). Now QAM has been around for about 40 yrs so there is nothing new there - I think the secret is all about the chip technology which is used as both receiver & transmitter. So while they say the transmission technology is open market I suspect the chip technology isn't which explains why it is so hard to get any tech info beyond "it uses QAM" Share this post Link to post Share on other sites
Numb-nuts 1 Posted April 19, 2015 I think you need to keep in mind just what baluns are. They are simply an impedance matching transformer - nothing more nothing less. The better ones have a small amount of filtering built in but unless that is an issue then it would come down to manufacturing quality. There is nothing mystical about HDCVI. Toss do u have some tech info about HDCVI ? Thats a NO then...Ewan? Share this post Link to post Share on other sites
the toss 0 Posted April 19, 2015 Then maybe you could fill us in Numby Share this post Link to post Share on other sites
ak357 0 Posted April 19, 2015 I've been digging for a while with not much results but I'll give you the bits Ive got. Basically HDcvi , HDtvi & Ahd are transmission techniques based on Quadrature Amplitude Modulation (QAM). Now QAM has been around for about 40 yrs so there is nothing new there - I think the secret is all about the chip technology which is used as both receiver & transmitter. So while they say the transmission technology is open market I suspect the chip technology isn't which explains why it is so hard to get any tech info beyond "it uses QAM" Yep, I heard the same plus I was told that CVI and TVI using carrier between 25-35 Mhz Thx Did u try to scope output ? Share this post Link to post Share on other sites
secplus 0 Posted April 20, 2015 These are the ones I have used before with CVI with no problems http://www.dh-vision.com/index.php/accessories/connectors-converters/dh-vbp-101.html Share this post Link to post Share on other sites
Numb-nuts 1 Posted April 20, 2015 These are the ones I have used before with CVI with no problems http://www.dh-vision.com/index.php/accessories/connectors-converters/dh-vbp-101.html Those are identical to the ones I already keep in stock they are very reliable and the push fit terminals work very smoothly especially when used with wire-end ferrules. Thank you for that, it's very reassuring. Share this post Link to post Share on other sites
secplus 0 Posted April 23, 2015 These are the ones I have used before with CVI with no problems http://www.dh-vision.com/index.php/accessories/connectors-converters/dh-vbp-101.html Those are identical to the ones I already keep in stock they are very reliable and the push fit terminals work very smoothly especially when used with wire-end ferrules. Thank you for that, it's very reassuring. A compliment coming from you? you made my day!! Share this post Link to post Share on other sites
Numb-nuts 1 Posted April 23, 2015 These are the ones I have used before with CVI with no problems http://www.dh-vision.com/index.php/accessories/connectors-converters/dh-vbp-101.html Those are identical to the ones I already keep in stock they are very reliable and the push fit terminals work very smoothly especially when used with wire-end ferrules. Thank you for that, it's very reassuring. A compliment coming from you? you made my day!! If you want to take credit for them you're welcome to do so. Just don't ask me to reset your password,,,, ( methinks this does not require explanation?) I buy them from Dynamic in Middlesborough, like everything they sell, they're the tops. I understand that Oprema are also a good solid seller. Share this post Link to post Share on other sites
secplus 0 Posted April 24, 2015 If you want to take credit for them you're welcome to do so. Just don't ask me to reset your password,,,, ( methinks this does not require explanation?) I buy them from Dynamic in Middlesborough, like everything they sell, they're the tops. I understand that Oprema are also a good solid seller. Well buddy I'm on the other side of the pond so Oprema is kinda far.. Share this post Link to post Share on other sites
hippiejoe 0 Posted May 29, 2015 HD-CVI is intended to produce 1080p or 720p over existing coaxial or Siamese cable. From my reading you should never use Cat5e with CVI as the signal decreases drasmatically the further out you go. If I had Cat5e, I would opt for IP cameras and an NVR. If you are already committed down that path, just run a good quality coax that is all copper and no aluminum parts. Share this post Link to post Share on other sites
topchips 0 Posted June 2, 2015 What was the distance on your longest run? Iv tested HDCVI on 300m cat5 e no issues, ground loop isolators also work on HDCVI, was using PV-207 balun http://lsvt.com.cn/pro_view.asp?Shop_ID=1209 works extremely well, the quality of your cat5 is very important and can cause the interference. Share this post Link to post Share on other sites
SunnyKim 2 Posted June 2, 2015 Topchips, Which one is more expensive? Coaxial cable or Siamese cable or Cat5e? Share this post Link to post Share on other sites
topchips 0 Posted June 2, 2015 Topchips,Which one is more expensive? Coaxial cable or Siamese cable or Cat5e? SunnyKim Well we only sell Siamese ( we call Poweraxial ), and cat5, it works out almost the same if you compare the price of BNC (R2.49) and the price of a Balun (R22.00) eg: 100m powerax with 2x BNC works out R408,79 and 100m cat5 with 2x balun is R422,94 that's of-course in South Africa don't know what your pricing is, However you can put 2 cameras on one length CAT5 so will work out in the end Cheaper, But I would still recommend Powerax all the time,less to no interference, I should mention we only use solid copper core high quality cables. Share this post Link to post Share on other sites
Numb-nuts 1 Posted June 3, 2015 Really chaps, the cost of the materials is irrelevant. If you do an installation and have to pull the wire and satrt again with a better or more suitable woe where's the economy in that? From my perspective if cat5 with baluns works well , then frankly cat5 is easier to work with, no de-reelers (no twisting) needed, lighter and therefore easier to handle. For me cat5 is the first choice every time but thats just my personal choice. Share this post Link to post Share on other sites