Search results
Results from the WOW.Com Content Network
A balun / ˈ b æ l ʌ n / (from "balanced to unbalanced", originally, but now derived from "balancing unit") [1] is an electrical device that allows balanced and unbalanced lines to be interfaced without disturbing the impedance arrangement of either line. [2] A balun can take many forms and may include devices that also transform impedances ...
The equipment side winding of the transformer does not need to be so carefully balanced. In fact, one leg of the equipment side can be earthed without effecting the balance on the line as shown in figure 5. With transformers the sending and receiving circuitry can be entirely unbalanced with the transformer providing the balancing. [2]
However, connecting an unbalanced circuit to, for instance, a twisted pair line, which is an intrinsically balanced format, makes the line susceptible to common-mode interference. [citation needed] For this reason, balanced lines are normally driven from balanced circuits. One option is to redesign the circuit so that it is properly impedance ...
These can also be used for splitting signals, balancing unbalanced signals, or feeding a balanced signal to unbalanced equipment. Transformers are also used in DI boxes to convert high-impedance instrument signals (e.g., bass guitar) to low impedance signals to enable them to connect to a microphone input on the mixing console.
The connections are arranged so that, as far as possible in each group, equal power is drawn from each phase. Further up the distribution system, the currents are usually well balanced. Transformers may be wired to have a four-wire secondary and a three-wire primary, while allowing unbalanced loads and the associated secondary-side neutral ...
Balanced and unbalanced circuits can be interfaced by the use of a balun, often through a DI unit (also called a "DI box" or "direct box"). As a last resort a balanced audio line can be fed into an unbalanced input and vice versa as long as the electronic design used for the output stage is known.
One example of this method involves a television balun transformer. This transformer allows interfacing a balanced line (300-ohm twin-lead) and an unbalanced line (75-ohm coaxial cable such as RG-6). To match the impedances, both cables must be connected to a matching transformer with a turns ratio of 2:1.
Equivalent unbalanced and balanced networks. The impedance of the series elements in the balanced version is half the corresponding impedance of the unbalanced version. Fig. 3. To be balanced, a network must have the same impedance in each "leg" of the circuit. A 3-terminal network can also be used as a 2-port.