how long can we run catv coaxial cable for cctv use without having any picture quality loss?

It is not recommended to use CATV cable for video at all. If you do, I would say not more than 100 ft..

thank you sir survtech. what would be the picture degradation be? it will become blur?

50-50 chance of major interference .. on and off or all the time.

The primary problems could be (depending on how far you try to run it):
* Weak sync
* Loss of contrast
* Excessive color (caused by distorted color burst signal)
* Ghosting or ringing

thats why i get humbars. is cable also the problem?

Possibly, but it also could be a ground loop.

sir for ground loop isolator where do i connect it? at the end of the cable entering the dvr? or at camera?

It probably doesn't matter, though I would try it at the DVR end since that should be the easiest place to get to. If it doesn't at least minimize the bars, you may have another problem (cables?).

ah i see. thanks. sir survtech are your familiar with vicon system? what protocol for speed dome do they support?

Sorry, no. The only PTZ'z I've worked with are Pelco, A/D and Ganz.

sir i have read on the forum that you are doing casino cctv. for casino what brand do they usually use? and is the recording per second more than 30fps?

We use Pelco, Ganz, Ikegami and a few other cameras. Our DVR system records approximately 1000 cameras - all at 30fps.

so there are many dvrs stack on racks. do you still use analog sir? or all are ip based?

100% analog cameras at this time.

sir are you familiar with vicon system?

Sorry, no.

thanks