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dodge0790

PTZ messes up during day. Jagged vertical lines. (WITH PICS)

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Hello I purchased this PTZ camera from Ebay It's a GVI Security (AHP-3136S) PTZ Outdoor 36x Zoom 650TVL

 

So during the night everything works great. But as soon as it turns daylight around 6-7am in the morning it starts to get these jagged vertical lines on the screen.

These lines will last all day until right around the sun sets about 5pm. I also have done a factory default reset checked all the timers and schedules.

 

Also If the camera is unplugged at night and left off till the middle of the day and then you plug it in it will instantly have the same jagged vertical lines.

 

Here's the best video I have of right as it starts in the morning. http://youtu.be/Uj32Suu_0Hc

 

img0792fr-1.jpg

 

So I thought maybe the sun is bothering it so I brought the camera inside and hooked it up.

Next morning same lines even inside.

Plus I shined the brightest flashlight inside the lens and it didn't bother it at all.

 

 

I have tried a new DVR , cables , power supply.

 

I currently have it hooked up with Cat5e cables.

img0886fo-1.jpg

 

Could it be some kind of ground loop problem? I don't have a ground going to it because my power box doesn't have one.

img0887an-1.jpg

 

Update: This morning , it isn't has bad has in the picture. but you can still tell there's some kind of interference.

 

Please guys any help would be appreciated this is literally driving me crazy.

 

 

Here's a picture right before it does it.

 

img0793u-1.jpg

Edited by Guest

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Do you have any equipment running during the times that the camera is affected? Motors, fans, compressors, fridge units etc etc.. It sounds like there could be some electrical interference from something else causing this.

 

What switches on at around sunrise and switches off at sunset in your building? If you can find that, then try switching it off and see if that is whats causing your problem

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Wow, thats a first, usually its the other way around. Yeah I agree, its gotta be some type of interferance from somewhere. That PTZ is a good one too so I dont think its that thats the problem.

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Could it still have interference even though it only runs through about 6feet of Cat5e straight to the DVR?

Do they make some kind of Power Filter that I could try?

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Use a separate power cable 18/2....

 

You cant run AC power over cat5e and not expect video interference.

 

 

So I ran the power separate and I still have interference.

Only thing through the Cat5e is the Video and Rs485.

Power is in a separate 18/2 cable.

 

 

--------

 

Next thing I tried is running just a normal BNC video cable separate from the power and rs485 and bingo! No lines no nothing clear as a bell!

I'm still confused why it would do that during the day time and not a night despite being inside a dark room.

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Next thing I tried is running just a normal BNC video cable separate from the power and rs485 and bingo!

 

 

its because you did not run baluns when using cat5. BNC =75ohms cat5 =100ohms fitted balun = 75ohms (at both ends)

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Maybe this is just one of those jobs where it would be easier to use siamese with seperate wires. Or use something like this:

DSCF1381JPG-1.jpg

 

It seems that every week someone is having problems with cat5 installations. Not saying that its an inferior way of doing things at all, but maybe for one time installers who are not proficient with these things, it would be a better option to use siamese.

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That is common if you are not using a balun and are using cat5 or telco wire over any distance.

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Hey,

 

I don't have much experience, but I did use the same style BNC to twisted pair connectors and had a similar problem.

 

Afterwards, I purchased a balun from newegg, named:

 

Aposonic Video Balun RJ-45 to BNC Converter with Power Input (A-XRJMBNC) - OEM

 

I'm not sure if it's safe to hook up female power plugs , to your current supply? Maybe someone more experienced can chime in...

 

Or else, you can get switching power supply(s) and pigtail power splitters.

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Gee we've run 24V AC over cat 5e for years. Don't think that's your issue... In fact we use 24V AC mostly because of ground loop issues we tend to find at times using DC.

 

Not using baluns....now there is issue number 1 and is probably your only issue.

 

Based on the pics you provided just get baluns put in there and let us know how that worked out and if it fixed the issue.

 

Something like this found on amazon work great as an example...

 

http://www.amazon.com/GEM-BLN-MTL2-VIDEO-BALUN-PASSIVE/dp/B005Y6L5BI/ref=sr_1_1?ie=UTF8&qid=1328631965&sr=8-1

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Use a separate power cable 18/2....

 

You cant run AC power over cat5e and not expect video interference.

Yes you can. In bench-testing various baluns, I ran 24VAC and video through 800' of Cat5e still coiled in the box, not a whit of interference. The twists in the wire are specifically designed to prevent cross-talk between pairs.

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It seems that every week someone is having problems with cat5 installations.

And most of the time it turns out that they're either not listening, not paying attention to what they're doing, or don't bother to RTFM. Like in this case, not using baluns - PEBKAC, Code ID-10-T, chiprack interface... aka user error.

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Apart from the lack of baluns, the original poster has also mis-wired the 24vAC. They need to connect the blue and orange wires to one phase of their 24v supply, and the remaining white wires to the other phase. If they do this, the twisted pairs will cancel out the interference from the AC supply.

What pattern on the screen is problably being caused by a switchmode power supply. Maybe from a nearby PC, a TV, or nearly anything. It will be coming in with the 24v power, and will be coupled (crosstalk) onto the video signal. Without baluns, the video signal is unbalanced, and is very susceptable to crosstalk.

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Apart from the lack of baluns, the original poster has also mis-wired the 24vAC. They need to connect the blue and orange wires to one phase of their 24v supply, and the remaining white wires to the other phase. If they do this, the twisted pairs will cancel out the interference from the AC supply..

I've never done it this way, and it's never been a problem - I use blue and blue/white for video, orange and orange/white for DC+ or AC hot, and green with green/white for DC ground or AC neutral.

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No worries. I consider the 24vAC to be another signal, so reckon that it may as well go down a pair to minimise crosstalk. The lack of baluns is the real killer here.

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The problem here is twofold. First by not using baluns there is an impedance mismatch

( 75^/100^ ) This results in an unbalanced transmission path & causes loss of the noise immunity that is characteristic of twisted pair. Now if the ONLY problem was the impedance mismatch then the result would more than likely be a phasing problem (ghosting). The interference displayed in the picture is typical of an external electrical interference getting onto the transmission path because of the reduced noise immunity created by the impedance mismatch ( lack of baluns ). The other clue is that the interference is only there during the day

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