balun

A balloon is a flexible bag normally filled with gas. Some balloons are purely decorative, others are used for specific purposes. Early balloons were made of dried animal bladders. Modern balloons can be made from materials such as rubber, latex, chloroprene or a nylon fabric. Balloon - Usage of balloons. small balloons (volume of a few litres) toy balloon decoration solar balloon balloon mail as part of a balloon flight competition or to spread information

Most simply, an antenna (U.S.) or aerial (UK) is an electronic component designed to transmit or receive radio waves. The words "antenna" and "aerial" are used throughout this article with precisely the same meaning. More specifically, an antenna is an arrangement of conductors designed to radiate (transmit) an electromagnetic field in response to an applied alternating electromotive force ...

Including:

• Antenna radio - Overview
• Antenna radio - Antenna parameters
• Antenna radio - Resonant frequency
• Antenna radio - Gain
• Antenna radio - Bandwidth
• Antenna radio - Impedance
• Antenna radio - Polarization
• Antenna radio - Efficiency
• Antenna radio - overview of antenna parameters
• Antenna radio - Transmission and reception
• Antenna radio - A few basic antenna models
• Antenna radio - Combination of multiple antennas

Read more here: » Antenna radio: Encyclopedia - Antenna radio

See also balance, equilibrium. In electronics, a balanced signal is one that is expressed as the difference between two conductors, as opposed to an unbalanced signal that is expressed as the difference between one conductor and a reference earth. Low voltage differential signaling, twin-lead and standard low-impedance microphone cables are all examples of balanced signals. In all three of these applications, noise in a cable run is reduced by the fact that most of the noise is picked up equally by both conductors, and so the signal expressed as the difference between the ...

Read more here: » Balanced: Encyclopedia - Balanced

Dipole antenna - Set-top TV antenna. The most common dipole antenna is the kind used with televisions called "rabbit ears". While theoretically the dipole elements should be along the same line "rabbit ears" are adjustable in length and angle. Larger dipoles are sometimes hung in a V shape with the center near the radio equipment on the ground or the ends on the ground with the center supported. Shorter dipoles can be hung vertically. Dipole antenna - Folded Dipole. Another common place one can see dipoles is an antenna for the FM band - a folded ...

See also:

Dipole antenna, Dipole antenna - Dipole Characteristics, Dipole antenna - Radiation pattern, Dipole antenna - Feeder Line, Dipole antenna - Common Applications of Dipole Antennas, Dipole antenna - Set-top TV antenna, Dipole antenna - Folded Dipole, Dipole antenna - Shortwave Antenna, Dipole antenna - Whip Antenna, Dipole antenna - Dipoles vs. marconi whip antennas, Dipole antenna - Dipole Towers, Dipole antenna - Colinear antenna systems based on dipoles, Dipole antenna - Dipole Types, Dipole antenna - Ideal Half Wavelength Dipole, Dipole antenna - Folded Dipole, Dipole antenna - Infinitesimal Dipole, Dipole antenna - Dipole as a Reference Standard, Dipole antenna - Dipole with Baluns, Dipole antenna - Current Balun, Dipole antenna - Coax Balun, Dipole antenna - Sleeve Balun, Dipole antenna - External references

Read more here: » Dipole antenna: Encyclopedia II - Dipole antenna - Common Applications of Dipole Antennas

Oliver Heaviside developed the transmission line model, also known as the telegrapher's equations, that describes how electrical voltage and current vary along a conductor. The theory applies to high-frequency transmission lines (such as telegraph wires and radio frequency conductors) but is also important for designing high-voltage energy transmission lines. The equations consist of two linear differential equations in time and position: one for V(x,t) and the other one for I(x,t). The model demonstrates that the electrical current can be reflected on the wire, and that wave patterns can appear along the line. ...

See also:

Transmission line, Transmission line - History, Transmission line - The four terminal model, Transmission line - Telegraphers equations, Transmission line - The equations, Transmission line - Direction of signal propagation, Transmission line - Cable impedance variation with frequency, Transmission line - Example, Transmission line - Practical types of electrical transmission line, Transmission line - Coaxial cable, Transmission line - Microstrip, Transmission line - Stripline, Transmission line - Balanced lines, Transmission line - General applications of transmission lines, Transmission line - Transfering signals from one point to another, Transmission line - Pulse generation, Transmission line - Lecher lines, Transmission line - Acoustic transmission lines, Transmission line - Patents, Transmission line - Reference

Read more here: » Transmission line: Encyclopedia II - Transmission line - Telegraphers equations

Transformer - Cores. Transformers for use at power or audio frequencies have cores made of many thin laminations of silicon steel. By concentrating the magnetic flux, more of it is usefully linked by both primary and secondary windings. Since the steel core is conductive, it, too, has currents induced in it by the changing magnetic flux. Each layer is insulated from the adjacent layer to reduce the energy lost to eddy current heating of the core. A typical laminated core is made from E-shaped and I-shaped p ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - An analogy, Transformer - Flux coupling laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classifications, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Enclosure, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Audio transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Construction

An active DI unit contains a preamplifier. Active DI units can therefore provide gain, and are inherently more complex and versatile than passive units. Active DI units require a power source, which is normally provided by batteries, by phantom power, or both. Cheaper units offering both options may perform far better on fresh batteries than on phantom power, or vice versa, so it is important to test a prospective pur ...

See also:

DI unit, DI unit - Passive DI units, DI unit - Active DI units, DI unit - Unit selection, DI unit - Headphone outputs, DI unit - Electric keyboards, DI unit - Electric guitar or bass, DI unit - Instrument amplifiers

Read more here: » DI unit: Encyclopedia II - DI unit - Active DI units

There are several critical parameters that affect an antenna's performance and can be adjusted during the design process. These are resonant frequency, impedance, gain, aperture or radiation pattern, polarization, efficiency and bandwidth. Transmit antennas may also have a maximum power rating, and receive antennas differ in their noise rejection properties. Antenna radio - Resonant frequency. The resonant frequency is related to the electrical length of the antenna. This is usually the physical len ...

See also:

Antenna radio, Antenna radio - Overview, Antenna radio - Antenna parameters, Antenna radio - Resonant frequency, Antenna radio - Gain, Antenna radio - Bandwidth, Antenna radio - Impedance, Antenna radio - Polarization, Antenna radio - Efficiency, Antenna radio - Overview of antenna parameters, Antenna radio - Transmission and reception, Antenna radio - Basic antenna models, Antenna radio - Combination of multiple antennas

Read more here: » Antenna radio: Encyclopedia II - Antenna radio - Antenna parameters

There are several critical parameters that affect an antenna's performance and can be adjusted during the design process. These are resonant frequency, impedance, gain, aperture or radiation pattern, polarization, efficiency and bandwidth. Transmit antennas may also have a maximum power rating, and receive antennas differ in their noise rejection properties. Antenna radio - Resonant frequency. The resonant frequency is related to the electrical length of the antenna. This is usually the physical len ...

See also:

Antenna radio, Antenna radio - Overview, Antenna radio - Antenna parameters, Antenna radio - Resonant frequency, Antenna radio - Gain, Antenna radio - Bandwidth, Antenna radio - Impedance, Antenna radio - Polarization, Antenna radio - Efficiency, Antenna radio - overview of antenna parameters, Antenna radio - Transmission and reception, Antenna radio - A few basic antenna models, Antenna radio - Combination of multiple antennas

Read more here: » Antenna radio: Encyclopedia II - Antenna radio - Antenna parameters

Party balloons are mostly made of natural latex tapped from rubber trees and can be filled with air, helium, water, or any other suitable liquid or gas. The rubber makes the volume adjustable. Filling with air is done with the mouth or with a pump. When rubber balloons are filled with helium so that they float (restrained by ribbons or strings) they can hold their shape for only a few hours. The enclosed air or helium escapes through small pores in the rubber. If helium is used the gas escapes quicker than in the case of air because the helium at ...

See also:

Balloon, Balloon - Usage of balloons, Balloon - Balloons as flying machines, Balloon - Balloons as decoration or entertainment, Balloon - Balloons in medicine, Balloon - Records, Balloon - Maximum flight heights, Balloon - Balloon tank, Balloon - Usage of Balloons on other planets, Balloon - Balloons in movies

Read more here: » Balloon: Encyclopedia II - Balloon - Balloons as decoration or entertainment

A transformer usually has: two or more insulated windings, to carry current a core, in which the mutual magnetic field couples the windings. In transformers designed to operate at low frequencies, the windings are usually formed around an iron or steel core. This helps to confine the magnetic field within the transformer and increase its efficiency, although the presence of the core causes energy losses. Transformers made to operate at high frequencies may use other l ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - Flux coupling, Transformer - Electrical laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classification, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Construction

Transformer - Autotransformers. An autotransformer has only a single winding, which is tapped at some point along the winding. AC or pulsed DC power is applied across a portion of the winding, and a higher (or lower) voltage is produced across another portion of the same winding. Autotransformers are used to compensate for voltage drop in a distribution system or for matching two transmission voltages, for example 115 kV and 138 kV. For voltage ratios not exceeding about 3:1, an autotransformer is less costly, lighter, smaller and more efficient than a t ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - Flux coupling, Transformer - Electrical laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classification, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Transformer designs

Transformer - Classification. Transformers may be roughly classified by the power handled in the circuit, in watts (or, more accurately, VA (volt amperes)): Up to 1 watt: Signal transformers, interstage coupling 1 - 1000 watts: Small power transformers, filament transformers, audio output transformers 1 kilowatt - 1 megawatt: Power transformers; larger units in this range may be oil filled 1 megawatt and over: Large power transformers, used for substations, large electrical ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - Flux coupling, Transformer - Electrical laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classification, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Practical considerations

The transformer is one of the simplest of electrical devices. Its basic design, materials, and principles have changed little over the last one hundred years, yet transformer designs and materials continue to be improved. Transformers are essential in high voltage power transmission providing an economical means of transmitting power over large distances. The simplicity, reliability, and economy of conversion of voltages by transformers was the principal factor in the selection of alternating current power transmission in the "War of Current ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - An analogy, Transformer - Flux coupling laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classifications, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Enclosure, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Audio transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Introduction

Transformer - Classifications. Transformers are adapted to numerous engineering applications and may be classified in many ways: By power level (from fraction of a watt to many megawatts), By application (power supply, impedance matching, circuit isolation), By frequency range (power, audio, RF) By voltage class (a few volts to about 750 kilovolts) By cooling type (air cooled, oil filled, fan cooled, water cooled, etc.) By purpose (rectifier, arc furnace, ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - An analogy, Transformer - Flux coupling laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classifications, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Enclosure, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Audio transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Practical considerations

There are two fundamental types of antennas, which, with reference to a specific three dimensional (usually horizontal or vertical) plane, are either omni-directional (radiate equally in the plane) or directional (radiates more in one direction than in the other). All antennas radiate some energy in all directions but careful construction results in large directivity in certain directions and negl ...

See also:

Antenna radio, Antenna radio - Overview, Antenna radio - Antenna parameters, Antenna radio - Resonant frequency, Antenna radio - Gain, Antenna radio - Bandwidth, Antenna radio - Impedance, Antenna radio - Polarization, Antenna radio - Efficiency, Antenna radio - Overview of antenna parameters, Antenna radio - Transmission and reception, Antenna radio - Basic antenna models, Antenna radio - Combination of multiple antennas

Read more here: » Antenna radio: Encyclopedia II - Antenna radio - Overview

A passive DI unit typically consists of an audio transformer used as a balun. Typical turns ratio is about 500:1, to match a nominal 50 kΩ signal source such as the magnetic pickup of an electric guitar to a 100 Ω input. Less commonly, a passive DI unit may consist of a resistive load, with or without capacitor coupling. Such units are best suited to outputs designed for headphones or loudspeakers. The cheaper passive DI units are susceptible to hum, and passive units tend to be less versatile than active. However, they require no batteries, are simple to use, and the better units a ...

See also:

DI unit, DI unit - Passive DI units, DI unit - Active DI units, DI unit - Unit selection, DI unit - Headphone outputs, DI unit - Electric keyboards, DI unit - Electric guitar or bass, DI unit - Instrument amplifiers

Read more here: » DI unit: Encyclopedia II - DI unit - Passive DI units

Transformer - Autotransformers. Main article: Autotransformer An autotransformer has only a single winding, which is tapped at some point along the winding. AC or pulsed voltage is applied across a portion of the winding, and a higher (or lower) voltage is produced across another portion of the same winding. For voltage ratios not exceeding about 3:1, an autotransformer is less costly, lighter, smaller and more efficient ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - An analogy, Transformer - Flux coupling laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classifications, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Enclosure, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Audio transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Transformer designs

Transformer - Flux coupling. A simple single phase transformer consists of two electrical conductors called the primary winding and the secondary winding. The primary is fed with a varying (alternating or pulsed continuous) electric current which creates a varying magnetic field around the conductor and in the magnetic core (shaded grey). The secondary, which is placed in this varying magnetic flux, develops an electromotive force or EMF. If the ends of the secondary are connected toge ...

See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - Flux coupling, Transformer - Electrical laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classification, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Basic principles

Transformer - An analogy. The transformer may be considered as a simple two wheel 'gearbox' for electrical voltage and current. The primary winding is analogous to the input shaft and the secondary winding to the output shaft. In this comparison, voltage is equivalent to shaft speed, current to shaft torque. In a gearbox, mechanical power (speed multiplied by torque) is constant (neglecting losses) and is equivalent to electrical power (voltage multiplied by current) which is also constant. The gear ratio is equivalent to the transformer step up or down ratio. See also:

Transformer, Transformer - Introduction, Transformer - Basic principles, Transformer - An analogy, Transformer - Flux coupling laws, Transformer - Invention, Transformer - Practical considerations, Transformer - Classifications, Transformer - Losses, Transformer - High frequency operation, Transformer - Construction, Transformer - Cores, Transformer - Windings, Transformer - Insulation, Transformer - Shielding, Transformer - Coolant, Transformer - Terminals, Transformer - Enclosure, Transformer - Transformer designs, Transformer - Autotransformers, Transformer - Polyphase transformers, Transformer - Resonant transformers, Transformer - Instrument transformers, Transformer - Pulse transformers, Transformer - RF transformers, Transformer - Audio transformers, Transformer - Uses of transformers

Read more here: » Transformer: Encyclopedia II - Transformer - Basic principles