balun


Also found in: Dictionary, Thesaurus, Acronyms, Wikipedia.

balun

(bal -ŭn) See feeder.

Balun

 

a device in the antenna-feeder line of a radio transmitter or receiver that matches an unbalanced feeder with a balanced feeder or antenna, or a balanced feeder with an unbalanced antenna. Baluns are principally used at meter and decameter wavelengths.

Figure 1. Baluns: (a) single-section, (b) quarter-wave sleeve, (c) U-bend, (d) coaxial-slot coupling, (e) balun with mismatch compensated; (1) unbalanced line, (2) balanced line, (3) sleeve, (4) half-wave loop, (5) bridge, (6) slot, (7) coaxial transformer, (8) compensating open-ended stub, (9) balanced short-circuited stub; (L) inductance coil, (C) capacitor

At decamenter wavelengths baluns are most often composed of elements that have lumped parameters, such as capacitors, inductance coils, and transformers, and form, for example, single- and multiple-section electric filters (Figure 1,a; see page 26). At meter wavelengths baluns are composed of elements having distributed parameters forming, for example, a quarter-wave sleeve (Figure 1,b), a U-bend (Figure 1,c), or a coaxial-slot coupling (Figure l,d). All such baluns operate in a narrow frequency band; in order to widen the frequency band, various devices, consisting of short-circuited and open-ended stubs, are used to compensate for the mismatch (Figure l,e). Transformer baluns with ferrite cores are often used in feeder lines that carry moderate power (up to 10 kilowatts).

REFERENCES

Aizenberg, G. Z. Antenny ul’trakorotkikh voln [part 1]. Moscow, 1957.
Lavrov, G. A., and A. S. Kniazev. Prizemnye i podzemnye antenny. Moscow, 1965.
Drabkin, A. L., V. L. Zuzenko, and A. G. Kislov. Antenno-fidernye ustroistva, 2nd ed. Moscow, 1974.

G. A. KLIGER and V. I. KOMISSAROV

balun

[′ba‚lən]
(electricity)
A device used for matching an unbalanced coaxial transmission line or system to a balanced two-wire line or system. Also known as balanced converter; bazooka; line-balance converter.

balun

(electronics)
A transformer connected between a balanced source or load and an unbalanced source or load. A balanced line has two conductors, with equal currents in opposite directions. The unbalanced line has just one conductor; the current in it returns via a common ground or earth path.

balun

(BALanced UNbalanced) An adapter that connects a balanced line to an unbalanced line such as from XLR to RCA. A balanced line is one in which both wires are electrically equal. In an unbalanced line, such as a coax, one line has different properties from the other. See XLR connector and RCA connector.


RCA to XLR
This balun might be used to wire RCA outputs on a preamp to XLR inputs on an amplifier. (Image courtesy of CableCreation, www.cablecreation.com)







Twisted Pair to BNC
This balun enables a balanced twisted pair of wires to plug into an unbalanced BNC jack. The screw connectors (right) connect the two wires. (Image courtesy of Black Box Corporation, www.blackbox.com.)
References in periodicals archive ?
The components used for the filter balun were C1005 series capacitors from TDK and LQW15 series inductors from Murata.
Thus, a dual-band balun BPF is obtained, and both the dual center frequencies can be controlled by adjusting the circumference of entire coupled ring resonator and the length or loaded location of the open-circuited stubs, severally.
A number of years in gestation, Balun Canan takes the kernel that was the story and develops it into a multi-faceted narrative that deals more completely with questions of lack of communication between spouses and between races; socio-political repercussions from the Cardenista efforts to effect agrarian and educational change for the indigenous population; autobiographical references to the author's internal struggles; a more complex consideration of social and racial hierarchies; a heightened presence of the indigenous and, especially important for future development, a focus on oral and written communication or the power of words.
The new miniature baluns will provide reliable connections and impedance matching between balanced and unbalanced 75-ohm coaxial and 120ohm twisted cable.
In this paper, a planar vialess Marchand balun facilitating the fabrication and assembling has been presented and a novel back-to-back measured method has been proposed for saving the cost of balun testing, in which expensive four-port equipment can be substituted by two-port equipment.
The SHM design integrates a miniature spiral type Marchand balun at the LO port, an in-phase coupling network at the RF port, and a lumped element IF matching network along with the balanced HBT pair.
Another of the leading options now available through AAS Technology is their VBP2412DC-50 balun, which is considered to be one of the most durable balun products available on the commercial market.
Recently, Balun trekked to Idaho, Utah and Montana to learn more about what volunteer drivers face out west.
Balun Canan is largely autobiographical, drawn from the author's difficult personal experience growing up as the daughter of a prominent family in Comitan, Chiapas, amidst the social and political conflict precipitated by the attempts at agrarian reform of the Cardenas government of the 1930s.
Los convidados de agosto, Oficio de tinieblas y una larga lista de titulos, y a 33 anos de su fallecimiento en Tel Aviv --el 7 de agosto de 1974-- y 50 de la publicacion de su novela Balun Canan, conversamos con otra gran mujer; una mujer que ha recorrido parte de la vida cultural del siglo XX y del presente: la critica de arte Raquel Tibol.
Models VB43F and VB43FPD video balun transceiver/combiners send quality video over cables for up to 1,000 feet, eliminating the need for coaxial cable.
This thrilling new HDMI balun is designed especially for commercial and residential applications where long CAT6/STP cable runs are required.