hazim

I checked the system today and tried a similar camera to the ones installed, I connected it directly to the composite input of the screen and got a very good result. I connected one of te installed cameras via CAT-6 directly to the screen and get that same bad result that I'm facing. In conclusion, sending video via UTP + baluns makes some distortion to the video signal which will affect the image quality, while coaxial cable doesn't make distortion.

It's not an "old" LCD, it's an LED screen that have HDMI input which mean it's not old for sure. It's hard to find Orion and ViewZ screens around here. Thanks StanLee2066 for your help, but I'm wondering if the problem is because I used Cat-6E cable (2 cables, each for four cameras) along with 350m passive video baluns. The distance isn't big at all, say 20m for the first cable and 40m for the second cable. I used UTP to reduce cables. Here is info about the balun I used. I should have tried connecting a camera to the DVR directly and see the result, but didn't. I'm far form the installation place. When I go there I'll try it. Regards, Hazim

I mean any CRT TV size. 32" and bigger LCD/LED. The camera is analog 700TVL, it has BNC output. The system is PAL bot NTSC. The idea is that any good camera gives good and clear image on CRTs while worse image on LCDs and LEDs, even when using VGA and HDMI output from DVR to the screen.

Dear all. I used to install CCTV systems. Nowadays I'm installing 700TVL CCD Sony Effio-2 cameras which gives high resolution image. These cameras for example gives excellent image on the old CRT monitors/TVs, but worse image on LCDs and LEDs. I noted that big LED and LCD screens require using VGA or HDMI inputs rather than RCA for high resolution image. So I bought good DVRs with HDMI output to get the best possible image. After trying HDMI, I still see the CRT image is much better. I made a quick search on the net and noticed that there is special screens for CCTV, but anyway it's hard to get such screens in my area. Is there a specific LCD/LED brand that is able to give a really high resolution image for CCTV? Note that I tried changing the output resolution for the DVR and didn't get any real difference. This is the DVR that I'm using: http://www.icatchinc.com/eng/pt_spec.php?id=20120928003 Regards, Hazim

Dear. I'll install a DVR in an office, where there is a screen and the DVR will be connected to. There is another screen about 150m far from the DVR, it is to be connected to the DVR too, and be able to control the DVR from that place. I'll use CAT-6E (with baluns) to transmit the video signal, and I'll put a video splitter to connect the DVR with both screens. The problem now is how to control with the remote control from the other place (150m far). I prefer to use the same CAT-6 that I'll use only two lines from 8 lines of it. Do I need to use balun?! I may make a circuit on a PCB that does what I need, but not sure if it works, it's hard for me to try as this place is far from my living and work area. Any suggestions? Regards, Hazim

Not even a single reply

Yes I mean that the 75 Ohm resistor became open.

Dear all. I've installed two analog cameras in a warehouse about 70m long. The cameras worked well for several days, and few days ago in a rainy day both cameras stopped working. I found the problem was that the 75 Ohm resistor at the video signal output (smd resistor on camera PCB) was fused in both cameras. This could happen due to a lightning but no lightning happened that day. The coaxial cables of the cameras are placed on the top of the warehouse, and the cameras are installed on the iron of the warehouse, so I'm thinking if any charges for the "stormy" atmosphere was the reason. I've checked the cables and they are ok. Any ideas? Hazim, Regards.

No idea?

Dear all. It's my first post in this forum . I work in CCTV from around 3 years. I have a project and need to ask about something for it. There will be 5 analog cameras installed near each other but are far around 80m from the DVR. I preferred to use twisted pairs with baluns for the first time. As the distance isn't that big I'll use passive 330m baluns. The power cable should be taken from the DVR place to the cameras, 12V on 80m cable for 5 cameras (5x0.75A) isn't a good idea absolutely, due to the voltage loss that theoretically bigger than 12V. So I should use a 2x0.5mm cable alongside with the twisted pairs cable to transfer 220V AC to the cameras, and put a 12V DC power supply there... My question is: Does the 220V AC cable alongside the twisted pairs video transmission cable/cables make interference and disturb/parasitize the video image?? Regards, Hazim

Dear All. I've installed the cameras according to what we said here, the attached picture clarifies what I did. The distance between the 220V cable and the CAT-6 cable is 50cm at maximum and tends to zero at the ends. The image is very clear and there is no interference at all. Thank you.

Thank you all, the problem is solved, I'll use a 220V cable and use a 12V power supply/adapter at the cameras' side. No problem in using 220V cable as I mentioned before. The cable will be attached to another steel cable, both video (UTP) and 220V (power) cables will be "parallel" and 1 to 2 meters apart. I'm thinking in another issue/problem that I may face. As I said, the UTP cable will be used for 4 cameras, this cable is attached to a steel cable, what I'm thinking about is that with 50m UTP and the steel cable, the electromagnetic waves in the air may "condensate" in the wire or make a flux in it, which will make noise in the aligned UTP's video signals and distorts the image. Would this happens? Regards, Hazim

Sorry I was mistaken, the distance is 50m not 80m. Actually I didn't know what "conduit" means but now I knew. I'll not use a conduit but I'll use a steel wire and attach the cables with it, so it doesn't break under the pressure of snow and wind. The wires well be between two buildings roofs. As I see now, I have to choices: 1- Use to steel wires, about 1m apart, one for the UTP cable and the other one for the 220V cable. 2- Take a 220V line from the other building, where the cameras are installed (needs an OK from the building's owners), and put a battery and UPS and a power for powering the cameras. * The electricity here in Lebanon goes off for long times daily! a UPS is a must. There is one installed for the DVR. Choice #2 may cost a little more but I prefer it if the building owner said OK for using 220V for there building.

I mean using the UTP cable for the video of the cameras, and use a separate 2x0.5 cable for the 220V. I'm asking if putting these two cables all that distance beside each other, will cause an interference and disturb the video image. I hope I've clarified my question well.

Thanks for your recommendation, but I have the cameras to be installed, they are 12V. Also I'll use each twisted pair for a camera. I just need an answer for my question an my problem may be solved.