The BNC connector was developed as a result of the need to provide a high quality, robust connector that would be capable of being used in a wide variety of applications. Additionally it needed to be smaller than either the N-type or C-type connectors which were much larger. The specifications of the BNC connector naturally vary from one manufacturer to another and it is always best to ensure that the particular component being purchased is suitable for the intended application.
However there are a number of guidelines that can be used. The connector comes in two basic types:. Of the two versions of the BNC connector, the 50 ohm version is more widely used. Often the BNC connector is specified for operation at frequencies up to 4 GHz and it can be used up to 10 GHz provided the special top quality versions specified to that frequency are used. However it is wise to fully check the specification.
BNC connectors come in a variety of formats. Not only are there plugs and sockets but there are also adapters and also other items such as attenuators. BNC plugs are designed not only for the required impedance, but also to accept a particular coax cable format. In this way all the internal piece parts are compatible with the coaxial cable used. It is therefore necessary to specify the BNC plug for use the cable to be used.
Although there is some latitude, it is naturally best to select the correct cable format. In addition to this there are straight and right angled variants. Of these the straight connectors are the most widely used, although right angled connectors where the cable leaves the plug at right angles to the centre of the connector centre line are also available.
These are ideal in many applications where the cables need to leave the connector in this manner to ensure cables are in a tidy fashion, or where space is at a premium. Unfortunately right-angled connectors have a marginally higher level of loss than their straight through counterparts. This example illustrates a system with cameras, baluns, a video input and power output bridge, DVR and monitor. Let's start somewhat backwards at the monitor, and work our way out to the cameras.
It is important to note that these baluns are passive in this example. The video is sent from the camera to the bridge and power is sent from the bridge to the camera. We made use of a DVR, one power and video bridge and a Cat5e patch panel. Our intent was to illustrate a rack mountable solution. This is for video connection only. The power supply provides power to the Bridge and has an optional rack mounting plate, which is shown in the picture.
It plugs into a standard three-pronged V outlet and can power two bridges. At this point, a short Cat5e patch cable connects the front of the bridge to the front of the patch panel.
You could run Cat5e straight to the camera balun from the bridge and bypass the patch panel, but this method provides a cleaner appearance. The Cat5e wire supplies both the power and video signals to the balun. The balun converts the power and video signals back from the Cat5e cable to separate channels for the camera. Note that the power is subject to some distance limitations, determined in large part by the equipment being utilized.
These parts feature a monitor end balun with a 24v power adapter and send power and receives video over a cat5 cable. The camera end converts the 24v power down to 12v for the camera. Which end would likely depend on the availability of electricity at each location as active baluns do require their own power source. For an active system, an active balun is required on both the camera end and the monitor end. Both baluns in this instance do need to have a power source.
In either case the camera will need a local power source as well. The pin is connected to the coaxial cable and is the point of transmission between the cable and the device the cable is connected to. SMA connectors are commonly used for household television cable connections, and may therefore be more familiar to consumers. Bayonet describes the physical connector type and Neill and Concelman are the names of the BNC connector's two inventors. In earlier computer networks, BNC connectors with coaxial cables were used in Ethernet networks, but Ethernet networks are now more commonly connected by RJ45 connectors and CAT5-style cables.
BNC to 3. BNC to 6. BNC T-piece copy permalink. Connects to any BNC plug, allowing any signal to be split between two devices. Used to connect audio Headphones to a PowerLab Output. BNC to Alligator Clips differential copy permalink. BNC T-piece.
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