Introduction
CCTV Video Balun, A very simple and much useful electrical device used in Analog CCTV security surveillance system. CCTV Video Balun comes in a picture when there are two lines with different impedances. As we all know Analog CCTV system uses Co-axial cable with BNC connector, But in some cases if we wish to use UTP cable to transfer baseband video signal from CCTV camera to Recorder, balun plays very crucial role.
Table of Contents
What is Balun?
Balun is an electrical device and act as interface between balanced and unbalanced lines. Each line has its own impedance characteristics and value, balun allows those lines to be interfaced regardless of their impedance value. Now a days balun is simply derived from balancing unit.
Applications of balun
In order to achieve compatibility between the systems baluns are used. There are 3 major applications of balun.
- Radio and television
- Video
- Audio
What is CCTV Video Balun?
CCTV Camera uses coaxial cable to transmit baseband video signal to video recorders. Video baluns are used to couple video signals to UTP cables rather using coaxial cables. Video balun drastically increases video signal transmission distance, with video balun with CAT5/CAT6 cable we can transmit signals up to 400 mtr.
CCTV video balun is a passive device, no active component used. Clear video signal can be transmitted up to 400mtr in standard definition and up to 200mtr in high definition quality.
Understanding how balun functions in CCTV camera system?
We have a Analog HD camera that has male BNC connection with 75 ohm impedance. we have a transmission medium which is CAT5/CAT5e/CAT6 cable with 100 ohm impedance, remember here we have not used Co-axial cable to demonstrate the connection with Camera and DVR. in order to transmit signal we must achieve impedance matching between the transmission medium used. with 75 and 100 ohm impedance we will not be able to transmit signal on UTP cable. to eliminate this issue we use video balun which acts as a balancer between BNC and UTP cable without worrying about the impedance.
CAT6 cable allow signal to transmit over 300mtr which is quite impressive as compared to coaxial cable.
Specification of HD Passive Video Balun
| Particulars | Specification |
| Number of Channel | 1 Channel |
| Transmission Distance | AHD/CVI: 400m (max) TVI/CVBS: 200m (max) |
| Transmission media | UTP CAT5/CAT5e/CAT6 |
| Coaxial Video connector | BNC- Male |
| UTP Connection | 2 Pin Push Terminal |
| Supported Formats | AHD/HDCVI/HDTVI/CVBS |
| Supported Resolution | 720P/960P/1080P/3MP/4MP/5MP |
| Impedance | BNC Male- 75 Ohms UTP Cable- 100 Ohms |
Video balun wiring diagram : (Passive to Passive)
How CCTV Balun works?
CCTV Video balun comes in pair. as you can see in above image we have Video balun A which is connected to AHD camera via BNC- male connector. balun A is connected to balun B via UTP CAT5/CAT5e/CAT6 cable (indicated in blue color). At the other end (DVR end) we need balun to get the signal that can be recorded on DVR. Video balun B is then connected to DVR BNC-male port.
Connection Flow
Camera –> Balun A –> UTP Cable –> Balun B–> Digital Video Recorder
we can summarize the working of video balun as we can convert the signal from analog camera which use coaxial cable to transmit the video signal to use CAT5e cable instead.
Advantages of using CCTV Video Balun
- Allow cost effective structured cabling
- Eliminate the traditional RG6 coax wire
- Increased transmission distance with UTP cable drastically decreasing the cost.
- Simple to use
- Passive device- There is no need of power supply to operate the video balun.