Wednesday, September 28, 2005

Como trabajaba newton?

En física, un newton(N) es la unidad de fuerza en el Sistema Internacional de Unidades, nombrada así en reconocimiento a Isaac Newton por su trabajo en la mecánica clásica. Se define como la fuerza necesaria para acelerar un objeto de 1 kg de masa a 1 m/s².

En el caso de que busques alguna tecnica de hax0rs para entender como funcionan las cosas, te recomendamos que leas entonces los tips para webmasters en donde aprenden a posicionar sitios web con tecnicas SEO de ultima generacion.


Es una unidad unidad derivada del SI, que se compone de las unidades básicas kg × m × s-2.

Como el peso es la fuerza que actúa entre dos objetos, por efecto de la gravedad, el newton es también una unidad de peso. Una masa de un kilogramo en la superficie de la Tierra tiene un peso de unos 9.81 newtons. Un newton es aproximadamente el peso de una manzana pequeña, curioso, si se tiene en cuenta la historia del descubrimento de la gravedad de Newton.

Monday, September 19, 2005

Rita sería el próximo huracán que azote los Estados Unidos

La tormenta tropical Rita está a punto de transformarse en un huracán al superar sus vientos los 115 kilómetros por hora.

Rita estaba a sólo cuatro kilómetros por hora de convertirse en un ciclón de categoría uno, la mínima en la escala de intensidad Saffir-Simpson (de cinco), según un boletín de las 18.00 GMT de hoy del Centro Nacional de Huracanes (CNH) de los EE.UU., con sede en Miami.

Una tormenta se transforma en huracán cuando sus vientos superan los 119 kilómetros por hora.

Evacuaciones en Cuba

En La Habana, más de 126.000 personas podrían ser evacuadas ante la inminente amenaza de la tormenta, y en previsión de posibles inundaciones en la costa norte de las provincias del centro y occidente de la isla.

La presidenta de la Comisión Provincial de Evacuación en Ciudad de La Habana, Oneida del Toro, dijo a medios locales que se acondicionan unos 660 albergues y cerca de 700 centros de elaboración de alimentos, para atender a los evacuados.

Camino a Florida

La tormenta ganó intensidad sobre Bahamas central, que comenzó a azotar hoy con fuertes vientos y copiosas lluvias, zona donde las aguas cálidas son combustible para que estos sistemas se fortalezcan.

El vórtice de Rita estaba cerca de la latitud 23,1 norte y longitud 75,9 oeste, a 265 kilómetros al sureste de Nassau y a 611 kilómetros al este-sureste de Cayo Hueso, en Florida.

Se desplazaba hacia el oeste-noroeste a 23 kilómetros por hora y se espera que continúe con este movimiento en las próximas 24 horas.

"En esta ruta, el centro de Rita pasará sobre o cerca de la isla Andros, en Bahamas, hoy en la noche y se acercará a los Cayos de Florida mañana por la mañana", advirtió el CNH.

Los meteorólogos han pronosticado que Rita se convertirá en huracán en las próximas horas y avanzará hacia el sur del estado de Florida, que aún no se ha recuperado del impacto del ciclón Katrina, el pasado 25 de agosto.

El gobernador de Florida, Jeb Bush, declaró ayer el estado de emergencia y hoy las autoridades del condado de Miami-Dade anunciaron la suspensión de las actividades escolares a partir de mañana.

A los turistas y residentes de los Cayos de Florida, en el extremo sur de la península floridana, se les ha ordenado ya que evacúen la zona, pues los pronósticos apuntan a que Rita impactará al sur de ese rosario de islas antes de penetrar en el golfo de México.

Las autoridades de esa zona suspendieron las clases, cerraron los tribunales y las oficinas públicas y han puesto en marcha una operación para acelerar la salida de las personas que desde ayer comenzaron a transitar por la única carretera que une a los Cayos con tierra firme.

El CNH emitió un "aviso" de huracán (paso antes de 24 horas) para el extremo sur y el sureste de la península norteamericana de Florida, incluidos los Cayos, así como el noroeste de las islas Bahamas.

Un "aviso" de tormenta tropical está vigente para las islas de Turcos y Caicos y para el sureste y este de Florida, donde también hay una "vigilancia" (paso 36 horas) de huracán.

Phillipe

En tanto, el huracán Philippe mantenía su intensidad cuando pasaba bien al oeste de las islas de Sotavento, en las Antillas menores, aunque su trayectoria prevista apunta hacia el norte del Atlántico, sin afectar en principio a islas y territorios.

En la activa temporada ciclónica del Atlántico norte, que comenzó el 1 de junio y terminará el 30 de noviembre, se han formado 17 tormentas tropicales y ocho huracanes: Dennis, Emily, Irene, Katrina, María, Nate, Ophelia y Philippe.

Dennis y Emily alcanzaron la categoría cuatro de la escala Saffir-Simpson y Katrina la categoría cinco, la máxima.
Katrina azotó el pasado 29 de agosto los estados de Louisiana, Mississippi y Alabama, y cuatro días antes Florida.

Las autoridades de los Estados Unidos continuaban contabilizando los muertos
dejados por Katrina, que superan ya los 800, y los daños económicos, que se esperan se acerquen a los 200.000 millones de dólares.

Fuente: EFE

Tragedia en Bariloche: un muerto al volcar micro de estudiantes

Un micro que llevaba 43 estudiantes secundarios se desbarrancó este mediodía en el pasaje "La Herradura", camino al Cerro Catedral, en San Carlos de Bariloche.

Claudio Pérez, socio de la empresa de transportes Quilaró SRL, desmintió a Infobae.com que sea su compañía la que transportaba a los estudiantes y dijo que era un "transportista particular" quien conducía a los egresados camino al Cerro Catedral. La empresa con la que los estudiantes habían contratado los servicios era "Estrella Cóndor", que habría subcontratado otra compañía para la excursión que terminó en tragedia.

Según trascendió, un menor falleció y varios chicos resultaron heridos cuando eran transportados a las aerosillas del Cerro Catedral.

El Dr. Carlos Delfino, director del Hospital Zonal de Bariloche, confirmó en Radio 10 que el joven que murió este mediodía se llamaba Darío Cocha, de 17 años.

"El chico fallecido es de sexo masculino y pertenecía al colegio Artigas de San Fernando", dijo Francisco Pope, director de prensa del municipio de Bariloche en la misma radio.

"El colectivo estaba detenido sobre la banquina para que los chicos sacaran fotos y ahí se desbarrancó. Hay sol, es un día con buen clima y no hay razones para el accidente. Quizá cedió el terreno", explicó la corresponsal de Telenueve.

Marcelo Diarti, rescatista y quien salvó a varios chicos de seguir atrapados entre los hierros retorcidos del micro, explicó en Radio 10 lo que vivió en Bariloche: "Vi el polvo cuando cayó el colectivo abajo y vi la locura esta de los chicos y el autobús sin techo... bajé con una soga y con el críquet de la camioneta... cuando llegué yo, ya estaba la Policía. La pendiente es bastante grande".

"Había tres chicos que estaban apretados, por eso bajé con el críquet. Y en seguida vinieron los bomberos... hay tres bastante heridos y uno fallecido", explicó el rescatista.

"Hay un muerto confirmado y heridos de diversos consideración que están siendo transportados al sanatorio San Carlos de Bariloche. Quedan muy pocos chicos atrapados", explicó.

Los alumnos accidentados pertenecen a las escuelas medias 10 de Tigre, 7 y 5 de Luján, y colegio José Artigas, de San Fernando.

Por su parte, la ministra de Salud de Río Negro, Adriana Gutiérrez, expresó en Radio 10 que el parte médico va a ser suministrado en una hora. "Una vez que hagamos el relevamiento, vamos a dar la información", dijo.

Los estudiantes fueron trasladados hacia el Hospital Privado Sanatorio del Sol y al Hospital zonal de Bariloche.

Los investigadores intentan determinar si hubo alguna falla mecánica o algún problema con los frenos que haya provocado el siniestro.

Tango 01 para los familiares
El director general de Escuelas bonaerense, Mario Oporto, informó hoy que otros dos aviones, entre ellos el Tango 01, partirán a Bariloche con familias de los jóvenes heridos, y retornarán esta noche con los adolescentes sin internación.

El Tango 01 partirá a las 21 junto con otro avión para transportar familiares de los jóvenes que permanecen hospitalizados.

Esos dos aviones regresarán a Buenos Aires con los adolescentes que no permanezcan internados.

El Gobierno busca promover celulares "made in Argentina"

El ministro de Planificación, Julio De Vido, anunció hoy que la Argentina pretende realizar una "sustitución eficiente" de celulares importados por aparatos de producción local.

"Es el círculo virtuoso de los prestadores de servicios comprando insumos nacionales", señaló De Vido en el cierre de un encuentro organizado por Telefónica de Argentina con proveedores de la firma.

El ministro estimó que de lograrse el reemplazo de los celulares importados por terminales nacionales "se van a crear 4.000 puestos de empleo directos y 12.000 indirectos".

Hace unas semanas el Gobierno formalizó en un acto en la Casa de Gobierno el lanzamiento de la fabricación de teléfonos móviles a cargo de una pyme argentina.

De acuerdo con la estadística de servicios públicos del Instituto Nacional de Estadística y Censos (INDEC), en julio pasado había en circulación en la Argentina 17,9 millones de celulares, cifra que supera a la de líneas de telefonía fija.

La mayoría de los equipos que circulan en el país son de origen brasileño, por lo que el reemplazo de las importaciones afectaría a las empresas radicadas en el país vecino.

Por su parte, el presidente de Telefónica de Argentina, Mario Vázquez, anunció hoy que la firma buscará insertar a sus proveedores locales dentro de la red de compras mundiales del grupo de telecomunicaciones español.

"Queremos ser una bisagra entre los proveedores locales para que estos puedan entrar en la red de compras mundiales de Telefónica", anunció Vázquez al término de un encuentro con empresarios en el Hotel Hilton.

El empresario dijo que es intención de la firma "colaborar con el desarrollo de proyectos conjuntos y con el desarrollo del país" y que tal objetivo está vinculado "al crecimiento del empleo en sectores empresariales, industriales y de servicios".

Cell Phones

Millions of people in the United States and around the world use cellular phones. They are such great gadgets -- with a cell phone, you can talk to anyone on the planet from just about anywhere!

These days, cell phones provide an incredible array of functions, and new ones are being added at a breakneck pace. Depending on the cell-phone model, you can:

  • Store contact information
  • Make task or to-do lists
  • Keep track of appointments and set reminders
  • Use the built-in calculator for simple math
  • Send or receive e-mail
  • Get information (news, entertainment, stock quotes) from the Internet
  • Play simple games.
  • Integrate other devices such as PDAs, MP3 players and GPS receivers

But have you ever wondered how a cell phone works? What makes it different from a regular phone? What do all those terms like PCS, GSM, CDMA and TDMA mean? In this article, we will discuss the technology behind cell phones so that you can see how amazing they really are.

If you are thinking about buying a cell phone, be sure to check out How Buying a Cell Phone Works to learn what you should know before making a purchase.

Let's start with the basics: In essence, a cell phone is a radio.

The Cell Approach
One of the most interesting things about a cell phone is that it is actually a radio -- an extremely sophisticated radio, but a radio nonetheless. The telephone was invented by Alexander Graham Bell in 1876, and wireless communication can trace its roots to the invention of the radio by Nikolai Tesla in the 1880s (formally presented in 1894 by a young Italian named Guglielmo Marconi). It was only natural that these two great technologies would eventually be combined.

In the dark ages before cell phones, people who really needed mobile-communications ability installed radio telephones in their cars. In the radio-telephone system, there was one central antenna tower per city, and perhaps 25 channels available on that tower. This central antenna meant that the phone in your car needed a powerful transmitter -- big enough to transmit 40 or 50 miles (about 70 km). It also meant that not many people could use radio telephones -- there just were not enough channels.

The genius of the cellular system is the division of a city into small cells. This allows extensive frequency reuse across a city, so that millions of people can use cell phones simultaneously.

Cell Phones and CBs
A good way to understand the sophistication of a cell phone is to compare it to a CB radio or a walkie-talkie.

  • Full-duplex vs. half-duplex - Both walkie-talkies and CB radios are half-duplex devices. That is, two people communicating on a CB radio use the same frequency, so only one person can talk at a time. A cell phone is a full-duplex device. That means that you use one frequency for talking and a second, separate frequency for listening. Both people on the call can talk at once.

  • Channels - A walkie-talkie typically has one channel, and a CB radio has 40 channels. A typical cell phone can communicate on 1,664 channels or more!

  • Range - A walkie-talkie can transmit about 1 mile (1.6 km) using a 0.25-watt transmitter. A CB radio, because it has much higher power, can transmit about 5 miles (8 km) using a 5-watt transmitter. Cell phones operate within cells, and they can switch cells as they move around. Cells give cell phones incredible range. Someone using a cell phone can drive hundreds of miles and maintain a conversation the entire time because of the cellular approach.


In half-duplex radio, both transmitters use the same frequency. Only one party can talk at a time.

In full-duplex radio, the two transmitters use different frequencies, so both parties can talk at the same time.
Cell phones are full-duplex.

In the next section, we'll look closer at the cellular approach.

Cell Engineering
In a typical analog cell-phone system in the United States, the cell-phone carrier receives about 800 frequencies to use across the city. The carrier chops up the city into cells. Each cell is typically sized at about 10 square miles (26 square kilometers). Cells are normally thought of as hexagons on a big hexagonal grid, like this:


Because cell phones and base stations use low-power transmitters, the same frequencies can be reused in non-adjacent cells. The two purple cells can reuse the same frequencies.

Each cell has a base station that consists of a tower and a small building containing the radio equipment (more on base stations later).

A single cell in an analog system uses one-seventh of the available duplex voice channels. That is, each cell (of the seven on a hexagonal grid) is using one-seventh of the available channels so it has a unique set of frequencies and there are no collisions:

  • A cell-phone carrier typically gets 832 radio frequencies to use in a city.
  • Each cell phone uses two frequencies per call -- a duplex channel -- so there are typically 395 voice channels per carrier. (The other 42 frequencies are used for control channels -- more on this later.)
  • Therefore, each cell has about 56 voice channels available.

In other words, in any cell, 56 people can be talking on their cell phone at one time. Analog cellular systems are considered first-generation mobile technology, or 1G. With digital transmission methods (2G), the number of available channels increases. For example, a TDMA-based digital system can carry three times as many calls as an analog system, so each cell has about 168 channels available (see the section on Cellular Access Technologies for lots more information on TDMA, CDMA, GSM and other digital cell-phone techniques).

Transmission
Cell phones have low-power transmitters in them. Many cell phones have two signal strengths: 0.6 watts and 3 watts (for comparison, most CB radios transmit at 4 watts). The base station is also transmitting at low power. Low-power transmitters have two advantages:

  • The transmissions of a base station and the phones within its cell do not make it very far outside that cell. Therefore, in the figure above, both of the purple cells can reuse the same 56 frequencies. The same frequencies can be reused extensively across the city.

  • The power consumption of the cell phone, which is normally battery-operated, is relatively low. Low power means small batteries, and this is what has made handheld cellular phones possible.
The cellular approach requires a large number of base stations in a city of any size. A typical large city can have hundreds of towers. But because so many people are using cell phones, costs remain low per user. Each carrier in each city also runs one central office called the Mobile Telephone Switching Office (MTSO). This office handles all of the phone connections to the normal land-based phone system, and controls all of the base stations in the region.

In the next section, you'll find out what happens as you (and your cell phone) move from cell to cell.

Cell Phone Codes

Cell Phone Codes

  • Electronic Serial Number (ESN) - a unique 32-bit number programmed into the phone when it is manufactured
  • Mobile Identification Number (MIN) - a 10-digit number derived from your phone's number
  • System Identification Code (SID) - a unique 5-digit number that is assigned to each carrier by the FCC

While the ESN is considered a permanent part of the phone, both the MIN and SID codes are programmed into the phone when you purchase a service plan and have the phone activated.

All cell phones have special codes associated with them. These codes are used to identify the phone, the phone's owner and the service provider.

Let's say you have a cell phone, you turn it on and someone tries to call you. Here is what happens to the call:

  • When you first power up the phone, it listens for an SID (see sidebar) on the control channel. The control channel is a special frequency that the phone and base station use to talk to one another about things like call set-up and channel changing. If the phone cannot find any control channels to listen to, it knows it is out of range and displays a "no service" message.

  • When it receives the SID, the phone compares it to the SID programmed into the phone. If the SIDs match, the phone knows that the cell it is communicating with is part of its home system.

  • Along with the SID, the phone also transmits a registration request, and the MTSO keeps track of your phone's location in a database -- this way, the MTSO knows which cell you are in when it wants to ring your phone.

  • The MTSO gets the call, and it tries to find you. It looks in its database to see which cell you are in.

  • The MTSO picks a frequency pair that your phone will use in that cell to take the call.

  • The MTSO communicates with your phone over the control channel to tell it which frequencies to use, and once your phone and the tower switch on those frequencies, the call is connected. Now, you are talking by two-way radio to a friend.

  • As you move toward the edge of your cell, your cell's base station notes that your signal strength is diminishing. Meanwhile, the base station in the cell you are moving toward (which is listening and measuring signal strength on all frequencies, not just its own one-seventh) sees your phone's signal strength increasing. The two base stations coordinate with each other through the MTSO, and at some point, your phone gets a signal on a control channel telling it to change frequencies. This hand off switches your phone to the new cell.


As you travel, the signal is passed from cell to cell.

In the next section, we'll talk about what happens when you leave your own provider's cell coverage area and enter another's. It's called roaming.

Roaming
Let's say you're on the phone and you move from one cell to another -- but the cell you move into is covered by another service provider, not yours. Instead of dropping the call, it'll actually be handed off to the other service provider.

If the SID on the control channel does not match the SID programmed into your phone, then the phone knows it is roaming. The MTSO of the cell that you are roaming in contacts the MTSO of your home system, which then checks its database to confirm that the SID of the phone you are using is valid. Your home system verifies your phone to the local MTSO, which then tracks your phone as you move through its cells. And the amazing thing is that all of this happens within seconds.

The less amazing thing is that you may be charged insane rates for your roaming call. On most phones, the word "roam" will come up on your phone's screen when you leave your provider's coverage area and enter another's. If not, you'd better study your coverage maps carefully -- more than one person has been unpleasantly surprised by the cost of roaming. Check your service contract carefully to find out how much you're paying when you roam.

Note that if you want to roam internationally, you'll need a phone that will work both at home and abroad. Different countries use different cellular access technologies. See the section on Cellular Access Technologies to learn more.

In the next section, you'll get a good look inside a digital cell phone.

Inside a Cell Phone
On a "complexity per cubic inch" scale, cell phones are some of the most intricate devices people use on a daily basis. Modern digital cell phones can process millions of calculations per second in order to compress and decompress the voice stream.


The parts of a cell phone

If you take a cell phone apart, you find that it contains just a few individual parts:

The circuit board is the heart of the system. Here is one from a typical Nokia digital phone:


The front of the circuit board

The back of the circuit board

In the photos above, you see several computer chips. Let's talk about what some of the individual chips do. The analog-to-digital and digital-to-analog conversion chips translate the outgoing audio signal from analog to digital and the incoming signal from digital back to analog. You can learn more about A-to-D and D-to-A conversion and its importance to digital audio in How Compact Discs Work. The digital signal processor (DSP) is a highly customized processor designed to perform signal-manipulation calculations at high speed.

The microprocessor handles all of the housekeeping chores for the keyboard and display, deals with command and control signaling with the base station and also coordinates the rest of the functions on the board.


The microprocessor

The ROM and Flash memory chips provide storage for the phone's operating system and customizable features, such as the phone directory. The radio frequency (RF) and power section handles power management and recharging, and also deals with the hundreds of FM channels. Finally, the RF amplifiers handle signals traveling to and from the antenna.


The display and keypad contacts

The display has grown considerably in size as the number of features in cell phones have increased. Most current phones offer built-in phone directories, calculators and games. And many of the phones incorporate some type of PDA or Web browser.


The Flash memory card on the circuit board

The Flash memory card removed

Some phones store certain information, such as the SID and MIN codes, in internal Flash memory, while others use external cards that are similar to SmartMedia cards.


The cell-phone speaker, microphone and battery backup

Cell phones have such tiny speakers and microphones that it is incredible how well most of them reproduce sound. As you can see in the picture above, the speaker is about the size of a dime and the microphone is no larger than the watch battery beside it. Speaking of the watch battery, this is used by the cell phone's internal clock chip.

What is amazing is that all of that functionality -- which only 30 years ago would have filled an entire floor of an office building -- now fits into a package that sits comfortably in the palm of your hand!



AMPS

Photo courtesy Motorola, Inc.
Old school: DynaTAC cell phone, 1983
In 1983, the analog cell-phone standard called AMPS (Advanced Mobile Phone System) was approved by the FCC and first used in Chicago. AMPS uses a range of frequencies between 824 megahertz (MHz) and 894 MHz for analog cell phones. In order to encourage competition and keep prices low, the U. S. government required the presence of two carriers in every market, known as A and B carriers. One of the carriers was normally the local-exchange carrier (LEC), a fancy way of saying the local phone company.

Carriers A and B are each assigned 832 frequencies: 790 for voice and 42 for data. A pair of frequencies (one for transmit and one for receive) is used to create one channel. The frequencies used in analog voice channels are typically 30 kHz wide -- 30 kHz was chosen as the standard size because it gives you voice quality comparable to a wired telephone.

The transmit and receive frequencies of each voice channel are separated by 45 MHz to keep them from interfering with each other. Each carrier has 395 voice channels, as well as 21 data channels to use for housekeeping activities like registration and paging.

A version of AMPS known as Narrowband Advanced Mobile Phone Service (NAMPS) incorporates some digital technology to allow the system to carry about three times as many calls as the original version. Even though it uses digital technology, it is still considered analog. AMPS and NAMPS only operate in the 800-MHz band and do not offer many of the features common in digital cellular service, such as e-mail and Web browsing.

Along Comes Digital
Digital cell phones are the second generation (2G) of cellular technology. They use the same radio technology as analog phones, but they use it in a different way. Analog systems do not fully utilize the signal between the phone and the cellular network -- analog signals cannot be compressed and manipulated as easily as a true digital signal. This is the reason why many cable companies are switching to digital -- so they can fit more channels within a given bandwidth. It is amazing how much more efficient digital systems can be.

Digital phones convert your voice into binary information (1s and 0s) and then compress it (see How Analog-Digital Recording Works for details on the conversion process). This compression allows between three and 10 digital cell-phone calls to occupy the space of a single analog call.

Many digital cellular systems rely on frequency-shift keying (FSK) to send data back and forth over AMPS. FSK uses two frequencies, one for 1s and the other for 0s, alternating rapidly between the two to send digital information between the cell tower and the phone. Clever modulation and encoding schemes are required to convert the analog information to digital, compress it and convert it back again while maintaining an acceptable level of voice quality. All of this means that digital cell phones have to contain a lot of processing power.



Wednesday, June 15, 2005

post de pruebinha

esto es una prueba para saber como funciona algo


Friday, May 27, 2005

How Lightsabers Work

Chances are that you have seen a lightsaber at one time or another, whether on the evening news or down at the local cantina. Therefore you know that a lightsaber is an amazing and versatile device that is able to cut through nearly anything in a matter of milliseconds.


Photo courtesy Lucasfilm Ltd.

Have you ever wondered how these remarkable weapons work? Where does the energy come from, and how are they able to contain that energy in a rod-like column of glowing power?

In this edition of HowStuffWorks, you will have a chance to look inside a lightsaber and discover the source of its incredible characteristics. Let's get started!

A lightsaber is a unique device, created by hand -- the controls will be slightly different on each individual lightsaber that you buy. But all lightsabers share the same general characteristics. If you were ever to pick up and examine a typical lightsaber, here are several things that you would immediately notice:

  • A lightsaber is normally about 30 centimeters long, about the size of a large flashlight.

  • At one end is the hand grip, belt ring and on/off switch (a.k.a., the Activation Matrix).

  • At the other end there is the blade arc tip and stabilizing ring.

  • Somewhere on the case (generally near the blade end of the lightsaber) you find one or two adjusting knobs for blade power and blade length.

When you turn on the lightsaber (*see important safety tips), you will notice the blade rapidly extending to its set length. You can adjust the length using the blade length adjusting knob. The lightsaber blade will make a distinctive sound that is typical of an arc wave energy field. You will also feel a gyroscopic effect in the handle, which again is a distinctive characteristic of the arc wave blade. This gyroscopic effect can take some getting used to, so be sure to handle any active lightsaber with extreme care until you are completely familiar with its feel and handling.

Slicing and Dicing
Once active, the blade of a lightsaber can be used in four different ways.

The most common use, of course, is slicing. A lightsaber is like a sword on steroids. Cutting through any human limb -- even an entire torso -- is trivial. It's like cutting through a banana with a machete.


A lightsaber can help convince an assailant that no means no.

With practice you can also use a lightsaber like a knife. For example, if you need to cut open the belly of a large domestic animal like a horse or a tauntaun, the lightsaber is the perfect tool. Simply use the tip of the blade and control the depth of your cut just like you would with a scalpel.

Nearly anything you would normally find around the home or office is easy to cut with a lightsaber, including steel pipes, reinforcing beams, mounting struts and so on. If you happen to find yourself hanging upside down in a cave, a lightsaber is the perfect tool to use to cut the rope.

Another common use is melting. For example, if you come upon a three-foot-thick blast door, you cannot "slice" your way through it like you can with a normal steel or concrete partition. But you can plunge the blade of your lightsaber straight into the door and then melt your way through it to cut out an opening. This normally takes several minutes, but the results are most impressive to anyone on the other side of the blast door.

Another important use of a lightsaber is deflection, in two different ways:

  1. A lightsaber blade can deflect another lightsaber blade and block its path.

  2. A lightsaber blade can deflect blaster bolts. In most cases you will want to deflect the bolts back at the person who shot them at you in the first place, but it is also possible to deflect them toward other objects and people in the room.
A lightsaber user with a strong affinity for the Force has a distinct advantage in the latter situation. By using the Force, the wielder can anticipate the path of the blaster bolt and align the blade with that path prior to the bolt's arrival. Using normal visual tracking to accomplish the same effect can be far more difficult.

Inside the Lightsaber
The construction of a lightsaber is a Jedi art passed down primarily by word-of-mouth from a Jedi master to his young Padawan learner. Therefore the interior features of any two lightsabers can vary in their details. However, the main features are remarkably consistent from lightsaber to lightsaber because of the common lineage of information.


The four major components inside any lightsaber include:

  • The power cell and associated components
  • The crystal energy chamber
  • The energy channel and blade arc tip
  • The controls
In the next sections we'll look at each of these elements in detail.

The Power Cell
Obviously a lightsaber contains a tremendous amount of energy -- far more than a blaster, for example. Any device that can melt its way through a three-foot-thick reinforced blast door in a matter of minutes obviously has access to tremendous energy reserves. Estimates range as high as several megawatt-hours of stored energy.

The source of this energy is a diatium power cell -- a device no larger than a roll of LifeSavers®. Diatium power cells are available from a variety of military and some civilian sources.

Surrounding the power cell is a power field conductor and the power vortex ring. These two devices work in concert with one another to move the available energy toward the energy gate. The energy gate controls the flow of energy into the crystal energy chamber.

The Crystal Energy Chamber
Really the heart of any lightsaber, the crystal energy chamber is responsible for primary energy conversion. At least two crystals (typically of the Adegan variety) are used in the energy chamber.

The first crystal is known as the primary crystal. It converts the energy channeling from the power assembly and then transfers its output to one or more focusing crystals. The focusing crystals are held in place by the focusing crystal activator.

The crystal energy chamber is the reason why all lightsabers are built by hand, and then only in the latter stages of Jedi training. The builder must align the crystals perfectly or risk detonation of the lightsaber upon activation. Only through the use of the Force can the proper alignment be guaranteed.

With several megawatt-hours of energy on tap, detonation is of course a catastrophic event. For this reason, initial activation is normally done remotely with an inexpensive droid.

The Energy Channel and Controls
The energy channel is where the actual lightsaber blade is generated. Energy flowing from the crystal energy chamber is converted to the arc wave that will become the blade. The arc wave flows up through the blade energy channel and past the cycling field energizers. These energizers are responsible for the gyroscopic effect discussed earlier in the article.

The refined arc wave makes its way to the blade arc tip and from there becomes visible as the glowing blade of the lightsaber that is so familiar.

The on/off switch, also known as the activation matrix, as well as the blade length and power adjustment controls are typically located near the cycling field energizers. Using these controls, the lightsaber's owner can tune the blade for specific applications.

Using Your Lightsaber Around the Home
Although a lightsaber is typically used as a defensive weapon by Jedi knights, the availability of lightsabers on consumer sites such as eBay is growing. It is a sad fact of life, but if a Jedi knight falls on hard times, his lightsaber is one source of quick cash. He can always build another one.

If you are lucky enough to acquire a lightsaber, you are probably purchasing it for personal defense purposes. A lightsaber completely blows away a can of pepper spray as a deterrent in muggings or robberies. However, many new owners are pleasantly surprised by the many domestic uses of a lightsaber around the home or office. Let's examine a few of the more common applications here, and then you can use your imagination to come up with others.


The big advantage of using a lightsaber, of course, is that you can both cut and toast the bagel in one stroke.


Hedge Trimming