Misplaced Pages

#178821

56-418: (Redirected from X-2 ) X2 may refer to: Computers [ edit ] X2 (protocol) , a pre-V.90 standard for 56k downstream modem communications Athlon 64 X2 , the first dual-core desktop CPU manufactured by AMD A two-lane PCI Express , slot A type of 10 Gigabit Ethernet , optical transceiver X2, a transport interface used to connect enodeBs in

112-411: A LTE/4G network Vehicles and transportation [ edit ] Aircraft, spacecraft and rockets [ edit ] Bell X-2 , an experimental supersonic aircraft Mitsubishi X-2 Shinshin , a Japanese experimental stealth fighter (formerly known as ATD-X) Orba , also known as X-2 , a planned British satellite Sikorsky X2 , a prototype, coaxial high-speed helicopter Skycycle X-2 ,

168-446: A digital modem  – one that connects directly to a digital telephone network interface, such as T1 or PRI – could send a signal that utilized every bit of bandwidth available in the system. While that signal still had to be converted back to analog at the subscriber end, that conversion would not distort the signal in the same way that the opposite direction did. The first 56k (56 kbit/s) dial-up option

224-508: A $ 30 million expansion: Déjà Vu , Goliath Jr. and the original X. This would bring the total to 15, beating the world coaster capital, Cedar Point . X was a prototype 4th Dimension roller coaster by Arrow Dynamics . The ride was planned to open in the summer of 2001, but the opening was delayed when it suffered design flaws. X opened for passholders on December 24, 2001, and officially opened on January 12, 2002. A month before opening, Arrow Dynamics filed for Chapter 11 bankruptcy due to

280-572: A 2010 music video game for the PlayStation 2 Final Fantasy X-2 , a 2003 role-playing video game Mega Man X2 , a 1994 platform game X2: The Threat , a 2003 space simulation game X2 (video game) , a 1997 video game X2, the main character in Star Wars Battlefront: Elite Squadron Film [ edit ] X2 (film) , a 2003 sequel to the 2000 film X-Men XXX: State of

336-549: A broken chain lift. It reopened in January 2014 with only a single train. The 3,610 ft (1,100 m) long layout features two inversions including a skydive, two " raven turns ", one backflip, and a twisting front flip. Each car on the train spins on its own independent axis 360 degrees forward or backward, which is being controlled by the outer rails of the track. Unlike traditional roller coasters, 4th Dimension roller coasters like X2 have four rails. After departing from

392-506: A complex social and political background in Japan) has several meanings, however, "Isn’t it great" or “Who cares” are some relevant meanings. This second 4th Dimension coaster is very similar to X2, but differs in height (Eejanaika is 250 feet (76 m) tall), and some elements are altered, such as the first 'half-half' element, in which the trains rotate on the track one half turn as the seats also rotate one-half turn, has now been replaced with

448-408: A given unit of time , usually expressed in bits per second (symbol bit/s , sometimes abbreviated "bps") or rarely in bytes per second (symbol B/s ). Modern broadband modem speeds are typically expressed in megabits per second (Mbit/s). Historically, modems were often classified by their symbol rate , measured in baud . The baud unit denotes symbols per second, or the number of times per second

504-451: A maximum speed of 76 mph (122 km/h). During the initial drop, the seat assembly is rotated so that riders are positioned facing the ground. There is a pool of fog at the base of the drop, however this effect has not worked in many years. The train then enters an inside raven turn, where the cars are rotated again halfway through the loop to create a "lie-to-fly" maneuver; riders transition from lying on their backs facing backward to

560-518: A medium with less than ideal characteristics, such as a telephone line that is of poor quality or is too long. This capability is often adaptive so that a modem can discover the maximum practical transmission rate during the connect phase, or during operation. Modems grew out of the need to connect teleprinters over ordinary phone lines instead of the more expensive leased lines which had previously been used for current loop –based teleprinters and automated telegraphs . The earliest devices which satisfy

616-400: A projected $ 10 million investment, X reopened on May 24, 2008, as X2. Six Flags Magic Mountain hired S&S Arrow to build new trains for X2. The new trains are lighter to reduce the amount of wear and downtime. X2 also took on a new load/unload method and third train to increase the ride capacity by 50%. Testing of the trains began on March 6, 2008. The attraction was closed in 2013 due to

SECTION 10

#1732772255179

672-413: A prone position, facing forward. After exiting the raven turn, the trains traverse a hill, during which the seat assemblies rotate backward 360 degrees, simulating a backflip. This is followed by a sweeping fan turn and a half twist "fly-to-lie" maneuver, in which riders flip forward 180 degrees to return to the original position of laying on their backs. Flame throwing special effects can be seen overhead as

728-608: A ride on X as part of a victory celebration of the Tampa Bay Buccaneers football team. On November 1, 2007, Six Flags Magic Mountain announced a redesign. X closed on December 2, 2007, to be redesigned including new trains with a pneumatic restraint system (an improvement over the original mechanically operated restraints that would frequently jam), a new color scheme of red track and black supports (originally pink track and yellow supports), and an all-new, innovative state-of-the-art visual, audio and sensory effects. In

784-677: A rocket used by Evel Knievel SpaceShipOne flight 17P , also known as X2, the second Ansari X Prize flight X-2 Dragonfly , the company designation of the Rotor-Craft XR-11 experimental helicopter of the late 1940s X-2 Rocket, the spacecraft used in Mission: Space in Epcot Center, Orlando, Florida Watercraft [ edit ] Bathyscaphe Trieste II , also known as X-2 , the US Navy bathyscaphe based on

840-601: A series of popular modems for the S-100 bus and Apple II computers that could directly dial out, answer incoming calls, and hang up entirely from software, the basic requirements of a bulletin board system (BBS). The seminal CBBS for instance was created on an S-100 machine with a Hayes internal modem, and a number of similar systems followed. Echo cancellation became a feature of modems in this period, which allowed both modems to ignore their own reflected signals. This way both modems can simultaneously transmit and receive over

896-438: Is near the theoretical Shannon limit of a phone line. While 56 kbit/s speeds had been available for leased-line modems for some time, they did not become available for dial up modems until the late 1990s. In the late 1990s, technologies to achieve speeds above 33.6 kbit/s began to be introduced. Several approaches were used, but all of them began as solutions to a single fundamental problem with phone lines. By

952-647: The Trieste HMS X2 , a Royal Navy submarine Kawasaki X2 , a personal water craft Other vehicles and transportation [ edit ] BMW X2 , a SUV vehicle produced by BMW North Wing Sport X2 , an American ultralight trike design SJ X2, used for the X 2000 train system in Sweden X2 (New York City bus) , a bus route X2, a Metrobus route , in Washington, D.C. Video games [ edit ] Dance Dance Revolution X2 ,

1008-698: The VA3400 which performed full-duplex at 1,200 bit/s over a normal phone line. In November 1976, AT&T introduced the 212A modem, similar in design, but using the lower frequency set for transmission. It was not compatible with the VA3400, but it would operate with 103A modem at 300 bit/s. In 1977, Vadic responded with the VA3467 triple modem, an answer-only modem sold to computer center operators that supported Vadic's 1,200-bit/s mode, AT&T's 212A mode, and 103A operation. A significant advance in modems

1064-757: The 1970s, independently made modems compatible with the Bell 103 de facto standard were commonplace. Example models included the Novation CAT and the Anderson-Jacobson . A lower-cost option was the Pennywhistle modem , designed to be built using readily available parts. Teletype machines were granted access to remote networks such as the Teletypewriter Exchange using the Bell 103 modem. AT&T also produced reduced-cost units,

1120-576: The SAGE director centers scattered around the United States and Canada . Shortly afterwards in 1959, the technology in the SAGE modems was made available commercially as the Bell 101 , which provided 110 bit/s speeds. Bell called this and several other early modems "datasets". Some early modems were based on touch-tone frequencies, such as Bell 400-style touch-tone modems. The Bell 103A standard

1176-521: The Smartmodem made communications much simpler and more easily accessed. This provided a growing market for other vendors, who licensed the Hayes patents and competed on price or by adding features. This eventually led to legal action over use of the patented Hayes command language. Dial modems generally remained at 300 and 1,200 bit/s (eventually becoming standards such as V.21 and V.22 ) into

SECTION 20

#1732772255179

1232-556: The Union , also known as X2 or xXx²: The Next Level , a 2005 American film Phones [ edit ] Nokia X2 , feature phone/smartphone Sendo X2 , a Series 60 mobile phone Sony Ericsson Xperia X2 , smartphone Other [ edit ] X2 (roller coaster) , at Six Flags Magic Mountain Chi-squared distribution , a theoretical probability distribution in inferential statistics Square (algebra) , also known as

1288-498: The algebraic square Keyboard sold by Korg in the 1990s X-2 Counter Espionage Branch , counterintelligence branch of the Office of Strategic Services See also [ edit ] 2X (disambiguation) [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change

1344-510: The connection between devices was normally manual, using an attached telephone handset . By the 1970s, higher speeds of 1,200 and 2,400 bit/s for asynchronous dial connections, 4,800 bit/s for synchronous leased line connections and 35 kbit/s for synchronous conditioned leased lines were available. By the 1980s, less expensive 1,200 and 2,400 bit/s dialup modems were being released, and modems working on radio and other systems were available. As device sophistication grew rapidly in

1400-522: The definition of a modem may have been the multiplexers used by news wire services in the 1920s. In 1941, the Allies developed a voice encryption system called SIGSALY which used a vocoder to digitize speech, then encrypted the speech with one-time pad and encoded the digital data as tones using frequency shift keying. This was also a digital modulation technique, making this an early modem. Commercial modems largely did not become available until

1456-417: The digitization itself placed constraints on the types of waveforms that could be reliably encoded. The first problem was that the process of analog-to-digital conversion is intrinsically lossy, but second, and more importantly, the digital signals used by the telcos were not "linear": they did not encode all frequencies the same way, instead utilizing a nonlinear encoding ( μ-law and a-law ) meant to favor

1512-576: The draft of a new 56 kbit/s standard V.90 with strong industry support. Incompatible with either existing standard, it was an amalgam of both, but was designed to allow both types of modem by a firmware upgrade. The V.90 standard was approved in September 1998 and widely adopted by ISPs and consumers. X2 (roller coaster) X2 (formerly known as X ) is a steel roller coaster at Six Flags Magic Mountain in Valencia , California . It

1568-432: The full spectrum of the phone line, improving the available bandwidth. Additional improvements were introduced by quadrature amplitude modulation (QAM) encoding, which increased the number of bits per symbol to four through a combination of phase shift and amplitude. Transmitting at 1,200 baud produced the 4,800 bit/s V.27ter standard, and at 2,400 baud the 9,600 bit/s V.32 . The carrier frequency

1624-710: The late 1950s, when the rapid development of computer technology created demand for a method of connecting computers together over long distances, resulting in the Bell Company and then other businesses producing an increasing number of computer modems for use over both switched and leased telephone lines. Later developments would produce modems that operated over cable television lines , power lines , and various radio technologies , as well as modems that achieved much higher speeds over telephone lines. A dial-up modem transmits computer data over an ordinary switched telephone line that has not been designed for data use. It

1680-601: The late 1980s, many modems could support improved standards like this, and 2,400-bit/s operation was becoming common. Increasing modem speed greatly improved the responsiveness of online systems and made file transfer practical. This led to rapid growth of online services with large file libraries, which in turn gave more reason to own a modem. The rapid update of modems led to a similar rapid increase in BBS use. The introduction of microcomputer systems with internal expansion slots made small internal modems practical. This led to

1736-418: The late 1990s and the emergence of smartphones in the 2000s led to the development of ever-faster radio-based systems. Today, modems are ubiquitous and largely invisible, included in almost every mobile computing device in one form or another, and generally capable of speeds on the order of tens or hundreds of megabytes per second. Modems are frequently classified by the maximum amount of data they can send in

X2 - Misplaced Pages Continue

1792-431: The late 1990s, telephone-based modems quickly exhausted the available bandwidth , reaching 56 kbit/s. The rise of public use of the internet during the late 1990s led to demands for much higher performance, leading to the move away from audio-based systems to entirely new encodings on cable television lines and short-range signals in subcarriers on telephone lines. The move to cellular telephones , especially in

1848-466: The lengthy introduction of the 28,800 bit/s V.34 standard. While waiting, several companies decided to release hardware and introduced modems they referred to as V.Fast . In order to guarantee compatibility with V.34 modems once a standard was ratified (1994), manufacturers used more flexible components, generally a DSP and microcontroller , as opposed to purpose-designed ASIC modem chips. This would allow later firmware updates to conform with

1904-590: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=X2&oldid=1211760223 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages X2 (protocol) Early modems were devices that used audible sounds suitable for transmission over traditional telephone systems and leased lines . These generally operated at 110 or 300 bits per second (bit/s), and

1960-427: The loading station, the ride makes a 180-degree turn traveling over the queue and onto the lift hill. After ascending 175 feet (53 m), the train enters a pre-drop and then ascends an additional 15 feet (4.6 m) to a maximum height of 190 feet (58 m). During this lift, riders are facing backwards. The first drop is 215 ft (66 m) and is sloped at 88.5 degrees, at the base of which ride vehicles attain

2016-824: The market around February 1997; although problems with K56Flex modems were noted in product reviews through July, within six months the two technologies worked equally well, with variations dependent largely on local connection characteristics. The retail price of these early 56k modems was about US$ 200 , compared to $ 100 for standard 33k modems. Compatible equipment was also required at the Internet service providers (ISPs) end, with costs varying depending on whether their current equipment could be upgraded. About half of all ISPs offered 56k support by October 1997. Consumer sales were relatively low, which USRobotics and Rockwell attributed to conflicting standards. In February 1998, The International Telecommunication Union (ITU) announced

2072-463: The market when V.32bis was standardized, which operated at 14,400 bit/s. Rockwell International 's chip division developed a new driver chip set incorporating the V.32bis standard and aggressively priced it. Supra, Inc. arranged a short-term exclusivity arrangement with Rockwell, and developed the SupraFAXModem 14400 based on it. Introduced in January 1992 at $ 399 (or less), it was half

2128-469: The mid-1980s. Commodore's 1982 VicModem for the VIC-20 was the first modem to be sold under $ 100, and the first modem to sell a million units. In 1984, V.22bis was created, a 2,400-bit/s system similar in concept to the 1,200-bit/s Bell 212. This bit rate increase was achieved by defining four or sixteen distinct symbols, which allowed the encoding of two or four bits per symbol instead of only one. By

2184-602: The modem sends a new signal. For example, the ITU-T V.21 standard used audio frequency-shift keying with two possible frequencies, corresponding to two distinct symbols (or one bit per symbol), to carry 300 bits per second using 300 baud. By contrast, the original ITU-T V.22 standard, which could transmit and receive four distinct symbols (two bits per symbol), transmitted 1,200 bits by sending 600 symbols per second (600 baud) using phase-shift keying . Many modems are variable-rate, permitting them to be used over

2240-400: The nonlinear response of the human ear to voice signals. This made it very difficult to find a 56 kbit/s encoding that could survive the digitizing process. Modem manufacturers discovered that, while the analog to digital conversion could not preserve higher speeds, digital-to-analog conversions could. Because it was possible for an ISP to obtain a direct digital connection to a telco,

2296-428: The originate-only 113D and the answer-only 113B/C modems. The 201A Data-Phone was a synchronous modem using two-bit-per-symbol phase-shift keying (PSK) encoding, achieving 2,000 bit/s half-duplex over normal phone lines. In this system the two tones for any one side of the connection are sent at similar frequencies as in the 300 bit/s systems, but slightly out of phase. In early 1973, Vadic introduced

X2 - Misplaced Pages Continue

2352-559: The outside of the coaster track in pairs. Four, 1-foot (0.30 m) tall rack gears move up and down following the profile of the seat rotation rails below the vehicle. This gear rotates the seats forwards and backward throughout the ride. The ride also has an on-board audio soundtrack that features five songs heard throughout the ride: S&S Arrow opened the second roller coaster of this type, Eejanaika at Fuji-Q Highland in Fujiyoshida, Yamanashi, Japan . Eejanaika (a word with

2408-564: The price of the slower V.32 modems already on the market. This led to a price war, and by the end of the year V.32 was dead, never having been really established, and V.32bis modems were widely available for $ 250 . V.32bis was so successful that the older high-speed standards had little advantages. USRobotics (USR) fought back with a 16,800 bit/s version of HST, while AT&T introduced a one-off 19,200 bit/s method they referred to as V.32ter , but neither non-standard modem sold well. Consumer interest in these proprietary improvements waned during

2464-412: The ride closed for its transformation into X2. It was completely repainted, received new third-generation trains, and featured new special effects including onboard audio, fog effects, and a pair of flame throwers . The ride reopened on May 24, 2008, following the upgrades. On December 19, 2000, Six Flags Magic Mountain announced that it would be adding three roller coasters for the 2001 season as part of

2520-625: The ride's misjudged costs stemming from Six Flags asking for a much larger ride than Arrow had successfully prototyped (This is covered in the 2016 documentary The Legacy of Arrow Development). The manufacturer had lost millions of dollars on the project. X was closed indefinitely in June 2002 due to issues with the trains. It was discovered that one of the coach seats that flipped riders was not moving smoothly. The ride reopened on August 13, 2002 after modifications were made to make it reliable. On February 8, 2003, Super Bowl MVP Dexter Jackson took

2576-413: The spin of the seats move up and down relative to the main track and spin the seats using a rack and pinion gear mechanism. These "rotation" rails don't support the train. The other two rails are for the weight-bearing wheels, capable of supporting these heavy trains. Weighing 5 t (4.9 long tons; 5.5 short tons), each vehicle has a wing-shaped design that spans 20 feet (6.1 m). Riders sit on

2632-467: The standards once ratified. The ITU standard V.34 represents the culmination of these joint efforts. It employed the most powerful coding techniques available at the time, including channel encoding and shape encoding. From the mere four bits per symbol ( 9.6  kbit/s ), the new standards used the functional equivalent of 6 to 10 bits per symbol, plus increasing baud rates from 2,400 to 3,429, to create 14.4, 28.8, and 33.6 kbit/s modems. This rate

2688-423: The time technology companies began to investigate speeds above 33.6 kbit/s , telephone companies had switched almost entirely to all-digital networks. As soon as a phone line reached a local central office, a line card converted the analog signal from the subscriber to a digital one and conversely. While digitally encoded telephone lines notionally provide the same bandwidth as the analog systems they replaced,

2744-416: The train enters an outside raven turn, with a brief pop of fog at the valley, immediately followed by another half twist. The track levels out and the train enters the final brake run before returning to the station. X2 is a unique prototype design in which the seats can rotate forward or backward 360 degrees in a controlled spin. This is achieved by having four rails on the track. The two rails that control

2800-499: Was 1,650 Hz in both systems. The introduction of these higher-speed systems also led to the development of the digital fax machine during the 1980s. While early fax technology also used modulated signals on a phone line, digital fax used the now-standard digital encoding used by computer modems. This eventually allowed computers to send and receive fax images. In the early 1990s, V.32 modems operating at 9,600 bit/s were introduced, but were expensive and were only starting to enter

2856-469: Was a proprietary design from USRobotics , which they called "X2" because 56k was twice the speed (×2) of 28k modems. At that time, USRobotics held a 40% share of the retail modem market, while Rockwell International held an 80% share of the modem chipset market. Concerned with being shut out, Rockwell began work on a rival 56k technology. They joined with Lucent and Motorola to develop what they called "K56Flex" or just "Flex". Both technologies reached

SECTION 50

#1732772255179

2912-458: Was integrated into devices from many other manufacturers. Automatic dialing was not a new capability—it had been available via separate Automatic Calling Units , and via modems using the X.21 interface —but the Smartmodem made it available in a single device that could be used with even the most minimal implementations of the ubiquitous RS-232 interface, making this capability accessible from virtually any system or language. The introduction of

2968-412: Was introduced by AT&T in 1962. It provided full-duplex service at 300 bit/s over normal phone lines. Frequency-shift keying was used, with the call originator transmitting at 1,070 or 1,270  Hz and the answering modem transmitting at 2,025 or 2,225 Hz. The 103 modem would eventually become a de facto standard once third-party (non-AT&T modems) reached the market, and throughout

3024-548: Was once a widely known technology, mass-marketed globally dial-up internet access . In the 1990s, tens of millions of people in the United States alone used dial-up modems for internet access. Dial-up service has since been largely superseded by broadband internet , such as DSL . Mass production of telephone line modems in the United States began as part of the SAGE air-defense system in 1958, connecting terminals at various airbases, radar sites, and command-and-control centers to

3080-536: Was the Hayes Smartmodem , introduced in 1981. The Smartmodem was an otherwise standard 103A 300 bit/s direct-connect modem, but it introduced a command language which allowed the computer to make control requests, such as commands to dial or answer calls, over the same RS-232 interface used for the data connection. The command set used by this device became a de facto standard, the Hayes command set , which

3136-422: Was the world's first fourth-dimension roller coaster and was the final roller coaster installed by ride manufacturer Arrow Dynamics . The ride is unique in that the trains' seats pitch 360 degrees forwards and in reverse independent of the main chassis. The coaster initially opened to the public on January 12, 2002; numerous issues delayed it from debuting in 2001 as was originally anticipated. On December 2, 2007,

#178821