Data baluns connect balanced lines to unbalanced lines in data transmission applications. They allow two different cable types to be joined together with a minimum amount of electrical gradation. Single-path data baluns provide an interface between older 75-ohm coaxial systems and 100-ohm or 120-ohm twisted pair wiring. Dual-path data baluns allow two different coaxial signals to be carried over a single length of twisted pair wire. Product specifications for both types of data baluns include maximum working voltage, isolation voltage, screen coupling, transient energy, direct current (DC) spark-over, impulse discharge, impedance and insertion loss. Features include onboard protection against lighting and transient spikes.
Data baluns differ in terms of mounting style and form factor. Rack-mounted systems are designed to be installed in standard 19-inch telecommunications racks. They usually conform to the G.703 standard from the International Telecommunications Union (ITU), an organization formerly known as the CCIT. Modular data baluns snap into place and are relatively easy to exchange or upgrade. Products that are protected by a recessed face plate are also easy to install. Data baluns that use digital distribution frame (DDF) blocks are also available. Typically, these products are designed for telecommunications applications which require high wiring densities.
Data baluns use coaxial, BNC, triax or twinax connectors. 1.0/2.3 coaxial connectors are designed for telecommunications systems which require sub-miniature, 50-ohm, slide-on or screw-on connections. 1.6/5.6 coaxial connectors are mechanically sturdy devices that feature a coupling mechanism. They are often used with telecommunications equipment that requires resistance against environmental and mechanical stress. Bayonet Neil-Concelman (BNC) connectors have a plastic dielectric and are used in RF applications to 2 GHz. Triax connectors are designed for use with triaxial cables where maximum RF shielding and minimum noise radiation is required. Twinax connectors are used with twinaxial cables for balanced low level and high sensitivity circuits.