Baluns and Ethernet

[alset 0]

Hi

 

I have a question regarding baluns, normally my systems are all IP so no problem as I run them in Cat7.

However I have taken over a property that has 10 analogue cameras complete with coax. I intend to add two High speed PTZ dome cameras which will have there own cables connected to a POE switch. my problem arises with wanting to change the whole system to an Ethernet based system. to that end can I replace the termination connection ( that entering DVR) with a BNC balun and then use the RJ45 to go to my switch.

I will then use a NAS for storage. I will use the existing power supplies to the old cameras.

Just cannot get my head around weather or not I can use just the one balun seems OK in theory.

[Securame 0]

What you are looking for is not a video balun, but an "ethernet over coax" adapter (or IP over coax). Something like this:

http://www.axis.com/sk/en/products/media-converters/axis-t8640

 

Probably once you find out about the prices and headaches you will prefer changing all the cabling from coax to UTP.

[RonR 0]

A balun changes impedance not the signal itself, in this case it allows analog video to travel on a twisted pair vs coaxial cable, but it is still an analog signal not digital.

 

If you are going to keep the analog cameras then you want a Video encoder, it converts an analog video signal to digital signal

 

They come in single and 4 channel, the 4 channel encodes 4 analog camera signals into 4 digital signals then combines them on 1 cat5, which connects to switch or directly to NVR, the NVR will recognize this signal as 4 separate cameras.

These encoders would be used where the coax cables terminate now, at the analog DVR, it allows you to use analog signals with network recorders.

Or if the analog coax cables are together at certain places and you can get a cat5 cable to that location from the recorder or switch then the video encoder(s) can be placed there.

 

 

If you are going to replace all the analog cameras with IP cameras then yes you can use existing coax cables for ethernet, but you would want to combine as many new IP cameras as practical in one area on a switch, then connect that switch to the NVR via existing coax using the above mentioned "ethernet over coax" units, as said it would be too expensive to do this per camera.