Planning a job for a local high school installing security TV. According to the salesman the very expensive cameras can do their job from the 50 ft high roof, aimed down at entrances. This is going to make the coax runs quite long. One may be 500 or 600 feet from the monitor...the others prob about 300. We are using the copper braided coax as we were told that CCTV unlike CATV uses the shield as a conductor.

What length restrictions apply and if a more direct route is impossible what kind of amplifier could be used to make this possible?

The 24 volts for each camera or group of cameras will be picked up near each camera location, as panels are nearby. Camera boxes will have heaters, and I will have to look at them to see what they draw at 24 volts...any input on how near to a group of 3 cameras my power supply would have to be to be OK? Could I go 100 feet to a couple of cameras with 24 volts for camera power and heater power?