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101-576: CD-R discs (CD-Rs) are readable by most CD readers manufactured prior to the introduction of CD-R, unlike CD-RW discs. Originally named CD Write-Once (WO) , the CD-R specification was first published in 1988 by Philips and Sony in the Orange Book , which consists of several parts that provide details of the CD-WO, CD-MO (Magneto-Optic), and later CD-RW (Re Writable). The latest editions have abandoned

202-426: A CD-RW disc, the recording layer is made of an alloy of silver and other metals—indium, antimony, and tellurium. In CD-R media, the dye itself can degrade, causing data to become unreadable. As well as degradation of the dye , failure of a CD-R can be due to the reflective surface. While silver is less expensive and more widely used, it is more prone to oxidation , resulting in a non-reflecting surface. Gold , on

303-406: A Zoned-CLV or CAV strategy, where the advertised maximum speed is only reached near the outer rim of the disc. This is not taken into account by the above table. (If this were not done, the faster rotation that would be required at the inner tracks could cause the disc to fracture and/or could cause excessive vibration which would make accurate and successful writing impossible.) The blank disc has

404-474: A mail order company that had started in the 1920s selling to amateur radio operators and electronics buffs. By April 1963, the Tandy Corporation acquired management control of RadioShack Corporation and within two years, RadioShack's $ 4 million (~$ 30.5 million in 2023) loss was turned into a profit under the leadership of Charles Tandy. Sales were going well for Tandy during this time. Under

505-407: A "MultiRead" certification are compatible. CD-RWs must be erased or blanked before reuse. Erasure methods include full blanking where the entire surface of the disc is erased and fast blanking where only metadata areas, such as PMA , TOC and pregap , are cleared. Fast blanking is quicker and usually sufficient to allow rewriting the disc. Full blanking removes all traces of the previous data, and

606-401: A 5-color silkscreen or offset press. Using a permanent marker pen is also a common practice. However, solvents from such pens can affect the dye layer. Since CD-Rs, in general, cannot be logically erased to any degree, the disposal of CD-Rs presents a possible security issue if they contain sensitive/private data. Destroying the data requires physically destroying the disc or data layer. Heating

707-401: A Power Calibration Area, used to calibrate the writing laser before and during recording. CDs contain two such areas: one close to the inner edge of the disc, for low-speed calibration, and another on the outer edge on the disc, for high-speed calibration. The calibration results are recorded on a Recording Management Area (RMA) that can hold up to 99 calibrations. The disc cannot be written after

808-511: A chain of tile and flooring stores, along with its other non-electronic businesses in 1975 to TandyCrafts. In 1985, Tandy acquired two chains, McDuff Electronics and VideoConcepts; the latter was previously owned by Eckerd Corporation . Most of these stores were closed as part of a 1994 restructuring plan, with 33 converted to RadioShack or Computer City Express stores. Remaining McDuff stores were closed in 1996. The Edge in Electronics,

909-461: A conventional CD player could be established in, and removed from, the medium by a laser operating at a different frequency. Tandy's announcement was surprising enough to "catch half a dozen industries off guard", claiming availability of consumer-level audio and video products below $ 500 by the end of 1990, and inviting other organisations to license the technology. The announcement attracted enthusiasm but also skepticism of Tandy's capability to deliver

1010-603: A couple of thousand Tandy Computer Centers around the country, instead of the Byte Shops and Computerlands we now see. And Tandy would have had a lot more control over Apple and other upstarts". In 1982 he wrote that while its thousands of stores were once a "considerable advantage" over competitors, "the Shack is falling way behind in sales outlets and thus in sales ... we've seen the Apple come along and, with fewer outlets, pass

1111-880: A development contract with Oklahoma-based software company Dorsett Educational Systems, known for its 25 years pioneering educational technology. The deal resulted in dozens of titles being released for the TRS-80 Color Computer. Radio Shack stores sold TRS-80 computers with other products, while Radio Shack Computer Centers only sold computers. Non-company-owned franchises sold Radio Shack products, including computers, and non-Radio Shack items. Value-added resellers distributed relabelled versions of Tandy computers. Despite selling computers through old-fashioned, department-store-like Sunday-newspaper inserts that emphasized price instead of technology and functionality, by 1980 InfoWorld described Radio Shack as "the dominant supplier of small computers". and in 1981 "one of

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1212-405: A disc from a prepared ISO image, for which the overhead would likely be trivial.) At the lowest write speeds, this overhead takes so much less time than the actual disc writing pass that it may be negligible, but at higher write speeds, the overhead time becomes a larger proportion of the overall time taken to produce a finished disc and may add significantly to it. Also, above 20× speed, drives use

1313-438: A furniture manufacturer, to Tandy Corporation. In 1994, Tandy Corporation offered O'Sullivan as a public company. In 1999, O'Sullivan was purchased for about $ 350 million (~$ 602 million in 2023) by investment group OSI Acquisition, an affiliate of Brockman, Rosser, Sherrill & Co., L.P. (BRS).{{ In 1973, Tandy launched a subsidiary company called Coppercraft Guild, which sold solid copper knickknacks and housewares through

1414-547: A given disc; these techniques are deviations from the compact disc (Red, Yellow, and/or Orange Book) standards, making the recorded discs proprietary-formatted and not fully compatible with standard CD players and drives. In certain applications where discs will not be distributed or exchanged outside a private group and will not be archived for a long time, a proprietary format may be an acceptable way to obtain greater capacity (up to 1.2 GB with GigaRec or 1.8 GB with HD-BURN on 99-minute media). The greatest risk in using such

1515-705: A high speed unblanked disc will cause the phase change layer to cool before blanking is achieved, preventing the data from being properly written. Similarly, using inappropriately high amounts of laser energy will cause the material to overheat and be insensitive to the data, a situation typical of slower discs used in a high powered and fast specification drive. For these reasons, older CD-RW drives that lack appropriate firmware and hardware are not compatible with newer, high-speed CD-RW discs, while newer drives can record to older CD-RW discs, provided their firmware correct speed, delay, and power settings can be appropriately set. The actual reading speed of CD-RW discs, however,

1616-500: A magnetic field to write the new data, in a manner essentially identical to Sony's MiniDisc and other magneto-optical formats. Reading the discs relied on the Kerr effect a major format flaw. The rewrite could only be read in special drives and was incompatible with non-magneto-optical enabled drives. The format was never released commercially, mostly because of incompatibility with standard CD reading units. Early CD-R media contained

1717-417: A mediocre writer, and discs written by such a writer cannot achieve their maximum potential archival lifetime. These times only include the actual optical writing pass over the disc. For most disc recording operations, additional time is used for overhead processes, such as organizing the files and tracks, which adds to the theoretical minimum total time required to produce a disc. (An exception might be making

1818-545: A now-defunct chain of boutique stores geared toward mall customers interested in fashionable personal and portable name brand electronics, debuted in 1990 and had 16 stores as of December 1993. One of the last stores open closed in San Antonio, Texas, in 2001. The Incredible Universe concept was Tandy's attempt to compete with other electronics giants such as Best Buy , Circuit City , and Lechmere . A joint venture between Tandy Corporation and Trans World Entertainment ,

1919-416: A pre-groove track onto which the data are written. The pre-groove track, which also contains timing information, ensures that the recorder follows the same spiral path as a conventional CD. A CD recorder writes data to a CD-R disc by pulsing its laser to heat areas of the organic dye layer. The writing process does not produce indentations (pits); instead, the heat permanently changes the optical properties of

2020-510: A process developed by Optical Data Inc., with research and development undertaken at Tandy's Magnetic Media Research Center. Known also as the Tandy High-Intensity Optical Recording system, THOR-CD media was intended to be playable in existing CD players, being compatible with existing CD audio and CD-ROM equipment, with the discs themselves employing a layer in which the "marks", "bumps" or "pits" readable by

2121-452: A proprietary data storage format, assuming that it works reliably as designed, is that it may be difficult or impossible to repair or replace the hardware used to read the media if it fails, is damaged, or is lost after its original vendor discontinues it. Nothing in the Red, Yellow, or Orange Book standards prohibits disc reading/writing devices from having the capacity to read/write discs beyond

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2222-444: A purchase, however small, in order to put them on the company's brochure mailing list, which often caused disgruntlement. A popular feature of Tandy stores was the free battery club, in which customers were allowed to claim a certain number of free batteries per year. In the early 1990s, the chain ran the 'Tandy Card' store credit card scheme and the 'Tandy Care' extended warranty policies which were heavily marketed by staff. In 1999,

2323-527: A similar compatibility flaw. Since the CD-MO was otherwise identical to CDs, the format still adopted a spiral-groove recording scheme, rendering the disc poorly suited as a removable medium for repeated, small-scale deletions and recordings. Some magneto-optical drives and media with the same form factor don't have this limitation. Unlike modern CD-RWs, CD-MO allowed for hybrid discs containing both an unmodifiable, pressed section, readable in standard drives, and

2424-513: A strategy to provide intensive leadership and tailored management of the three distinct and diverse businesses of the company, each of which recently had reached a substantial size. With this transition, RadioShack and Tandy Leather Company were no longer under the same corporate umbrella. Wray Thompson was promoted to president of Tandy Leather Company in 1976 and Dave Ferrill was promoted to the position of National Sales Manager; they oversaw 288 stores. Although they opened their 300th store that year,

2525-421: A writable MO section. The early introduction and no standards for disc recording software, file systems, and formats, physical incompatibility, coupled with more economical CD-R discs, led to abandoning the format. Other magneto-optical media, unbound by limitations of the typical CD-ROM filesystems, replaced the CD-MO. Rewritable media can, with suitable hardware, be re-written up to 100 000 times . The CD-RW

2626-440: Is applied to provide the recorder with an absolute time reference. Groove width is 0.6  μm and pitch of 1.6 μm . The media for CD-RW has the same layers as CD-R media. The reflective layer is, however, a silver - indium - antimony - tellurium ( AgInSbTe ) alloy with a polycrystalline structure and reflective properties in its original state. When writing the laser beam uses its maximum power ( 8-14 mW ) to heat

2727-493: Is based on phase change technology, with a degree of reflection at 15–25% , compared to 40–70% for CD-R discs. The properties of the medium and the write and erase procedure is defined in the Orange Book Part III . To maintain a precise rotation speed, tracks have a slight superimposed sinusoidal excursion of 0.3 µm at a frequency of 22.05  kHz . In addition a 1 kHz frequency modulation

2828-500: Is closed TOC information in the PMA is written into a lead-in area and the PCA and PMA are logically eliminated. The lead-out is created to mark the end of the data in the session. Like a CD-R, a CD-RW has hardcoded speed specifications which limit recording speeds to fairly restrictive ranges. Unlike a CD-R, a CD-RW has a minimum writing speed under which the discs cannot be recorded, based on

2929-457: Is no assurance that it can be made to do so again by service or adjustment. Discs with capacities larger than 650 MB, and especially those larger than 700 MB, are less interchangeable among players/drives than standard discs and are not very suitable for archival use, as their readability on future equipment, or even on the same equipment at a future time, is not assured unless specifically tested and certified in that combination, even under

3030-515: Is not "empty"; the pregroove has a wobble (the ATIP ), which helps the writing laser to stay on track and to write the data to the disc at a constant rate. Maintaining a constant rate is essential to ensure the proper size and spacing of the pits and lands burned into the dye layer. As well as providing timing information, the ATIP (absolute time in pregroove) is also a data track containing information about

3131-446: Is not a reliable guide to quality, because many brands (major as well as no name) do not manufacture their own discs. Instead, they are sourced from different manufacturers of varying quality. For best results, the actual manufacturer and material components of each batch of discs should be verified. Burned CD-Rs suffer from material degradation, just like most writable media. CD-R media have an internal layer of dye used to store data. In

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3232-552: Is not directly correlated or bound to speed specification, but depends primarily on the reading drive's capabilities. Many half-height CD and DVD writers released between 2004 and 2010, including the TSSTcorp SH-M522 combo drive (2004), Pioneer DVR-110D (2005), Hitachi-LG GSA-4167 (2005) , TSSTcorp SH-S182/S183 (2006) and SH-S203/TS-H653B (2007) have officially adapted support for CD-RW UltraSpeed Plus (32× Z-CLV ), while more recent DVD writers such as

3333-407: Is often used for confidentiality purposes. CD-RWs can sustain fewer re-writes compared to other storage media (ca. 1,000 compared up to 100,000). They are ideally used for test discs (e.g. for CD authoring ), temporary backups, and as a middle-ground between online and offline storage schemes. Before CD-RW technology, in 1990 a standard for magneto-optical recordable and erasable CDs called CD-MO

3434-458: Is recommended if using adhesive-backed paper labels that the labels be specially made for CD-Rs. A balanced CD vibrates only slightly when rotated at high speed. Bad or improperly made labels, or labels applied off-center, unbalance the CD and can cause it to vibrate when it spins, which causes read errors and even risks damaging the drive. A professional alternative to CD labels is pre-printed CDs using

3535-460: Is recovered ("decoded"). Once a section of a CD-R is written, it cannot be erased or rewritten, unlike a CD-RW . A CD-R can be recorded in multiple sessions. A CD recorder can write to a CD-R using several methods including: With careful examination, the written and unwritten areas can be distinguished by the naked eye. CD-Rs are written from the center outwards, so the written area appears as an inner band with slightly different shading. CDs have

3636-541: The Harvard Business School to further expand his education. As World War II escalated Charles was called to serve his country in the military and relocated to Hawaii. He wrote to his father from overseas suggesting that leathercraft might offer new possibilities for growing the shoe finding business since the same supplies were used widely in Navy and Army hospitals and recreation centers. Leathercraft gave

3737-654: The RIAA . Specifically, the price of every music CD-R includes a mandatory royalty disbursed to RIAA members by the disc manufacturer; this grants the disc an "application flag" indicating that the royalty has been paid. Consumer standalone music recorders refuse to burn CD-Rs that are missing this flag. Professional CD recorders are not subject to this restriction and can record music to data discs. The two types of discs are functionally and physically identical other than this, and computer CD burners can record data and/or music to either. New music CD-Rs are still being manufactured as of

3838-548: The SH-224DB (2013) and Blu-Ray writers such as the LG BE16NU50 (2016) have downgraded the backwards compatibility to CD-RW UltraSpeed (24× Z-CLV). Slim type optical drives are subject to physical limitations, thus are not able to attain rotation speeds of half-height (desktop) optical drives. They usually support CD-RW writing speeds of 16× or 24× Z-CLV in zones of 10× CLV, 16× CLV, 20× CLV and 24× CLV towards

3939-868: The personal computer revolution in 1977 by introducing complete pre-assembled microcomputers instead of a kit. Their TRS-80 (1977) and TRS-80 Color Computer ("CoCo") (1980) line of home computers were popular in the years before the IBM PC became commonplace, and had wide distribution in Radio Shack stores at a time when there were few computer stores . By 1981, computers were the most important part of Tandy's sales. The company attempted to monopolize software and peripheral sales by keeping technical information secret and not selling third-party products in Tandy-owned stores. An experimental Tandy computer store at company headquarters sold non-Tandy products until

4040-612: The $ 3,499 Tandy 6000 Xenix system. The company acquired GRiD Systems in March 1988. Grid Systems was a laptop manufacturer whose products included the GRiD Compass (1982), GRiDCase (1985), GRiDLite (1987), and GRiDPad (1989) tablet computer . Tandy also produced the short-lived Tandy 1100FD and Tandy 1100HD notebooks. Released in 1989, the 1100 Series was based on the popular NEC V20 processor clocked at 8 MHz. Tandy also produced software for its computers running DOS , in

4141-490: The 2010s, devices capable of writing to CD-Rs and other types of writable CDs could be found under $ 20. The dye materials developed by Taiyo Yuden made it possible for CD-R discs to be compatible with Audio CD and CD-ROM discs. In the United States, there is a market separation between "music" CD-Rs and "data" CD-Rs, the former being notably more expensive than the latter due to industry copyright arrangements with

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4242-594: The CD-R manufacturer, the dye used, and media information (disc length and so on). The pregroove is not destroyed when the data are written to the CD-R, a point which some copy protection schemes use to distinguish copies from an original CD. There are three basic formulations of dye used in CD-Rs: There are many hybrid variations of the dye formulations, such as Formazan by Kodak (a hybrid of cyanine and phthalocyanine). Many manufacturers have added additional coloring to disguise their unstable cyanine CD-Rs in

4343-469: The Compact Disc logo). CD-R recording systems available in 1990 were similar to the washing machine-sized Meridian CD Publisher, based on the two-piece rack mount Yamaha PDS audio recorder costing $ 35,000, not including the required external ECC circuitry for data encoding, SCSI hard drive subsystem, and MS-DOS control computer. On July 3, 1991, the first recording of a concert directly to CD

4444-471: The InterTAN stores were sold to rival Circuit City Inc. The stores were branded as RadioShack, however, because Circuit City lost the naming rights. Later, all of these RadioShacks were re-branded as " The Source by Circuit City " (now called just The Source). Some of these stores have since closed. In 2009, Circuit City sold The Source to Bell Canada Enterprises (BCE). In 1975, Tandy spun off Color Tile,

4545-538: The RMA is full, however, the RMA may be emptied in CD-RW discs. Real-life (not accelerated aging) tests have revealed that some CD-Rs degrade quickly even if stored normally. The quality of a CD-R disc has a large and direct influence on longevity—low-quality discs should not be expected to last very long. According to research conducted by J. Perdereau, CD-Rs are expected to have an average life expectancy of 10 years. Branding

4646-492: The Radio Shack name was a problem in the office". In the mid-1980s, it began selling peripherals compatible with non-Tandy products such as the IBM PC. The company also mandated in 1986 an IBM-like dress code for store employees. In 1987, BYTE wrote that "Tandy might now be offering the most extensive lines of computer products in the world", including the $ 99 Color Computer 2, $ 499 Model 102 notebook, various PC compatibles, and

4747-660: The RadioShack-style theme for a while, but these stores also closed in 2005. A new company called T2 Enterprises now continues using the old T2 Retail web presence as an exclusively on-line retailer stocking a range of RadioShack products and other electronics. In 2012, Tandy Corporation Ltd, a UK company, acquired the UK rights to the Tandy brand from RadioShack. It now operates as an on-line retailer of electronic components and kits at tandyonline.com. In Australia : In Canada ,

4848-465: The Red Book standard. Some hardware compatible with Red Book CDs may have difficulty reading CD-Rs and, because of their lower reflectivity, especially CD-RWs. To the extent that CD hardware can read extended-length discs or CD-RW discs, it is because that hardware has capability beyond the minimum required by the Red Book and Yellow Book standards (the hardware is more capable than it needs to be to bear

4949-639: The TRS-80 by in sales". Green warned that the company needed to make "soul-searching, perhaps painful, decisions". Tandy's market share—as high as 60% at one time—indeed declined by 1983 because of competition from the IBM PC and lack of third-party products. Tandy adopted the IBM PC compatible architecture with the Tandy 1000 and Tandy 2000 (1983–1984). The 1000 helped Tandy achieve a 25% personal computer market share in 1986, tied with Apple and in second place behind IBM. In 1982, Tandy Corporation entered into

5050-699: The Tandy Corporation name was dropped, and the entity became the RadioShack Corporation. Tandy began in 1919 when two friends, Norton Hinckley and Dave L. Tandy, decided to start the Hinckley-Tandy Leather Company and concentrated their efforts on selling sole leather and other supplies to shoe repair dealers in Texas. Hinckley and Tandy opened their first branch store in 1927 in Beaumont, Texas and in 1932, Dave Tandy moved

5151-540: The UK stores were acquired by Carphone Warehouse , as a part of an expansion strategy that saw the majority of the Tandy stores converted either to Carphone Warehouse or Tecno photographic stores. In May 2000, the Tandy name was dropped and the official name became RadioShack Corporation. By 2001, all former Tandy stores had been converted or closed. A small number of the stores were sold to a new company called T2 Retail Ltd formed by former Tandy (Intertan UK) employees, Dave Johnson, Neil Duggins and Philip Butcher who continued

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5252-416: The absence of explicit additional manufacturer specifications beyond normal compact disc logo certification, that any particular player or drive will perform beyond the standards at all or consistently. If the same device with no explicit performance specs beyond the compact disc logo initially handles nonstandard discs reliably, there is no assurance that it will not later stop doing so, and in that case, there

5353-424: The additional capacity, these discs have to be burned using overburn options in the CD recording software. Overburning itself is so named because it is outside the written standards, but, due to market demand, it has nonetheless become a de facto standard function in most CD writing drives and software for them. Some drives use special techniques, such as Plextor's GigaRec or Sanyo's HD-BURN, to write more data onto

5454-440: The assumption that the discs will not degrade at all. The polycarbonate disc contains a spiral groove, called the pregroove because it is molded in before data are written to the disc; it guides the laser beam upon writing and reading information. The pregroove is molded into the top side of the polycarbonate disc, where the pits and lands would be molded if it were a pressed, nonrecordable Red Book CD. The bottom side, which faces

5555-500: The best marketers in the computer industry". Adam Osborne that year described Tandy as "one of the great enigmas of the industry". He wrote of his amazement that a company "with so few roots in microcomputing" was the "number-one microcomputer manufacturer" while "selling computers out of Radio Shack stores, no less?" Green suggested in 1982 that stores separate computers from toys to convince "middle-income (-class) customers that Radio Shack stores are not primarily dealers in schlock for

5656-403: The compact disc standards. The standards do require discs to meet precise requirements in order to be called compact discs, but the other discs may be called by other names; if this were not true, no DVD drive could legally bear the compact disc logo. While disc players and drives may have capabilities beyond the standards, enabling them to read and write nonstandard discs, there is no assurance, in

5757-533: The company banned doing so. A market research company reported in 1981 that not selling others' products slowed Tandy's growth, and predicted that competitors would benefit. Discussing the report, Wayne Green , publisher of 80 Microcomputing , warned that the company might have become overconfident from defeating "poorly financed and inadequately managed competitors", and that IBM and others would not likely be "as myopic and hidebound as Radio Shack". He wrote that had Tandy continued its experiment, "they might have

5858-462: The company expanded into the hobby market, making leather moccasins and coin purses, making huge sales among Scouts , leading to a fast growth in sales. Aiming to broaden the company horizon, Charles Tandy acquired a number of craft retail companies, including RadioShack in 1963, then an almost bankrupt chain of electronics stores in Boston . In the 1970s and 1980s, now led by John Roach as CEO,

5959-639: The company introduced the Tandy Zoomer, a predecessor to the Palm Pilot , designed by Jeff Hawkins . Also that year, the company produced an interactive, multimedia CD-ROM player called the Tandy Video Information System (VIS). Like the Tandy computers, it was based on the IBM PC architecture and used a version of Microsoft Windows . Tandy even produced a line of floppy disks , and continued producing IBM PC compatibles until

6060-488: The company name was changed to Tandy Corporation. The corporate headquarters were also moved to Fort Worth, Texas, where Charles D. Tandy became the president and chairman of the board. Tandy Leather was operating 125 stores in 105 cities of the United States and Canada and expanding significantly. Tandy acquired the assets of Merribee Art Embroidery Co., manufacturer and retailer of needlecraft items, as well as five other companies, including Cleveland Crafts Inc. and brought on

6161-560: The corporation started to invest into the personal computer market following the introduction of the popular TRS-80 ; it was one of the pioneers in the rising personal computer industry, being lauded by the magazine Financial World as "the driving force at the front-running company in the red-hot personal computer race". Unable to keep up with cost-cutting competitors, Tandy exited the PC business in 1993, selling its assets to AST Research , retaining its profitable goods-making units. In 2000,

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6262-533: The disc at the tightest allowable tolerances specified in the Orange Book CD-R/CD-RW standards. The engineering margin that was reserved for manufacturing tolerance has been used for data capacity instead, leaving no tolerance for manufacturing; for these discs to be truly compliant with the Orange Book standard, the manufacturing process must be perfect. Despite the foregoing, most CD-Rs on

6363-415: The disc in a microwave oven for 10–15 seconds effectively destroys the data layer by causing arcing in the metal reflective layer, but this same arcing may cause damage or excessive wear to the microwave oven. Many office paper shredders are also designed to shred CDs. Some recent burners (Plextor, LiteOn) support erase operations on -R media, by "overwriting" the stored data with strong laser power, although

6464-399: The disc, the write beam heats the amorphous regions with low power to about 200 °C . The alloy is not melted, but returns to the polycrystalline state and is again reflective. During and after a disc authoring the distribution of data on the CD-RW varies. The following areas are present: Each session on a multi-session disc has a corresponding lead-in, PMA, PA and lead-out. When the session

6565-415: The dye, changing the reflectivity of those areas. Using a low power laser, so as not to further alter the dye, the disc is read back in the same way as a CD-ROM. However, the reflected light is modulated not by pits, but by the alternating regions of heated and unaltered dye. The change of the intensity of the reflected laser radiation is transformed into an electrical signal, from which the digital information

6666-881: The end of the Intel 486 era. In 1973, Tandy Corporation began an expansion program outside their home market of the US, opening a chain of RadioShack-style stores in Europe and Australia under the Tandy name. The first store to open was in Aartselaar , Belgium on August 9, 1973. The first UK store opened October 11, 1973, in Hall Green, Birmingham. Initially, these new stores were under direct ownership of Tandy Corporation. In 1986, Tandy Corporation formed its subsidiary InterTAN as separate entity though connections between them were still visible. For example, catalogue number compatibility

6767-418: The erased area cannot be overwritten with new data. The polycarbonate material and possible gold or silver in the reflective layer would make CD-Rs highly recyclable. However, the polycarbonate is of very little value and the quantity of precious metals is so small that it is not profitable to recover them. Consequently, recyclers that accept CD-Rs typically do not offer compensation for donating or transporting

6868-598: The first acquisition was with the American Handicrafts Company which featured a broad line of do-it-yourself handicraft products, two established retail stores in the New York market, and useful knowledge of school and institutional markets. Sixteen additional retail stores were opened in 1953, and by 1955 Tandy Leather was a thriving company with leased sales sites in 75 cities across the United States. Tandy Leather became an attractive commodity and

6969-435: The first of two retail stores in 1950 that specialized exclusively in leathercraft. Hinckley did not share the enthusiasm of Dave and Charles Tandy for the new leathercraft division. As a result, the two original founders came to an agreement in 1950 that Hinckley would continue to pursue the shoe findings business and the Tandy partners would specialize in promoting leathercrafts. The first Tandy Catalog, only eight pages long,

7070-529: The first two stores, located in Arlington, Texas , and Wilsonville, Oregon , opened in 1992. Each Incredible Universe store stocked more than 85,000 items, and the stores' sales personnel did not work on commission. Sales were below average compared to Tandy's profitable RadioShack line, and by late 1996, the company had decided to sell or close all 17 Incredible Universe stores. Many Incredible Universe stores were acquired by Fry's Electronics . Computer City

7171-471: The form of Tandy Deskmate . That same year, Tandy introduced the WP-2, a solid-state notebook computer that was a rebadged Citizen CBM-10WP. Eventually, in the early 1990s, Tandy Corporation sold its computer-manufacturing business to AST Computers , and all Tandy computer lines were terminated. When that occurred, Radio Shack stores began selling computers made by other manufacturers, such as Compaq . In 1992,

7272-399: The laser beam in the player or drive, is flat and smooth. The polycarbonate disc is coated on the pregroove side with a very thin layer of organic dye. Then, on top of the dye is coated a thin, reflecting layer of silver , a silver alloy , or gold . Finally, a protective coating of a photo-polymerizable lacquer is applied on top of the metal reflector and cured with UV light. A blank CD-R

7373-420: The laser in the writer, as well as correct timing of the laser pulses, stable disc speed, and so on, is critical to not only the immediate readability but the longevity of the recorded disc, so for archiving it is important to have not only a high-quality disc but a high-quality writer. In fact, a high-quality writer may produce adequate results with medium-quality media, but high-quality media cannot compensate for

7474-577: The late 2010s, although demand for them has declined as CD-based music recorders have been supplanted by other devices incorporating the same or similar functionality. Prior to CD-R, Tandy Corporation had announced a rewritable CD system known as the Tandy High-Density Optical Recording (THOR) system, claiming to offer support for erasable and rewritable discs, made possible by a "secret coating material" on which Tandy had applied for patents, and reportedly based partly on

7575-515: The leadership of Lloyd Redd (president) and Al Patten (VP of Operations), the company prospered. The number of Tandy store-fronts skyrocketed over the next five to six years by growing from 132 sites in 1969 to 269 sites in 1975. Ground broke in downtown Fort Worth for the construction of the Tandy Towers in 1975. The 18-story office building was initiated as phase I of a massive downtown development with plans to cover eight city blocks and become

7676-427: The market have an 80-minute capacity. There are also 90 minute/790 MB and 99 minute/870 MB discs, although they are less common and depart from the Orange Book standard. Due to the limitations of the data structures in the ATIP, 90 and 99-minute blanks will identify as 80-minute ones. As the ATIP is part of the Orange Book standard, its design does not support some nonstandard disc configurations. In order to use

7777-411: The material to 500–700 °C causing material liquefaction . In this state, the alloy loses its polycrystalline structure and reflectivity and assumes an amorphous state. The lost reflectivity serves the same function as bumps on manufactured CDs. The polycrystalline state of the disc forms the trenches. The scanning signal when reading is created by strong or weak reflection of the laser beam. To erase

7878-433: The materials. CD-RW CD-RW ( Compact Disc-Rewritable ) is a digital optical disc storage format introduced by Ricoh in 1997. A CD-RW compact disc (CD-RWs) can be written, read, erased, and re-written. CD-RWs, as opposed to CDs, require specialized readers that have sensitive laser optics. Consequently, CD-RWs cannot be read in many CD readers built prior to the introduction of CD-RW. CD-ROM drives with

7979-410: The men something useful to do and their handiwork, in addition to being therapeutic, had genuine value. Charles Tandy returned home from the service as a lieutenant commander in 1948 and negotiated to operate the fledgling leathercraft division himself. He had encouraged and followed the development of that venture through correspondence with his father. Within a short time Charles succeeded in opening

8080-408: The need to emancipate the company from continuing in the direction initiated by GAI. He used all his resources, raised additional money, and exercised his right to purchase the 500,000 shares of stock that were included in the original settlement. When the votes were counted on the day of that pivotal stockholders meeting, the Tandy group took management control of General American Industries. In 1961,

8181-463: The new headquarters of the Tandy Corp. It contained an upscale retail shopping center with an indoor ice skating rink and had its own privately owned subway system . The company's board of directors then announced a plan to separate Tandy's businesses into three distinct publicly held companies. The two new companies were named Tandycrafts, Inc. and Tex Tan-Hickok, Inc. This plan was publicized as

8282-458: The other hand, although more expensive and no longer widely used, is an inert material, so gold-based CD-Rs do not suffer from this problem. Manufacturers have estimated the longevity of gold-based CD-Rs to be as high as 100 years. By measuring the rate of correctable data errors , the data integrity and/or manufacturing quality of CD-R media can be measured, allowing for a reliable prediction of future data losses caused by media degradation. It

8383-545: The outer edge, of which the highest speed zone depends on availability. Tandy Corporation Tandy Corporation was an American family-owned retailer based in Fort Worth, Texas that made leather goods, operated the RadioShack chain, and later built personal computers . Tandy Leather was founded in 1919 as a leather supply store. By the end of the 1950s, under the tutelage of then-CEO Charles Tandy ,

8484-509: The owner, Werner Magnus, to help run the newly acquired Merribee division. The first Tandy Mart had twenty-eight different shops all devoted to craft and hobby merchandise and included American Handicraft, Tandy Leather, Electronics Crafts and Merribee in an area of about 40,000 square feet. Charles Tandy became intrigued with the potential for rapid growth that he saw in the electronics retail industry during 1962. He found RadioShack in Boston,

8585-440: The past, so the formulation of a disc cannot be determined based purely on its color. Similarly, a gold reflective layer does not guarantee the use of phthalocyanine dye. The quality of the disc is also not only dependent on the dye used, it is also influenced by sealing, the top layer, the reflective layer, and the polycarbonate. Simply choosing a disc based on its dye type may be problematic. Furthermore, correct power calibration of

8686-414: The phase change material's heating and cooling time constants and the required laser energy levels. Despite this, some professional audio CD recorders, such as those made by Tascam, use special techniques to bypass these limitations and can record high speed (but not ultra speed) discs in realtime. Since the CD-RW discs need to be blanked before recording data, writing too slowly or with too low energy on

8787-485: The popularity of Nature-Tand's products had begun to slide. Charles Tandy died on November 4, 1978, at the age of 60. Concurrently, key stakeholders began to question the direction of the company. Wray Thompson subsequently resigned from his position as president and later started The Leather Factory with Ron Morgan, which eventually purchased Tandy Leather Corporation in 2000. Tandy was one of three companies (along with Commodore International and Apple ) that started

8888-476: The store from Beaumont to Houston, Texas. Tandy's business survived the economic storms of the Depression, gathered strength and developed a firm presence in the shoe findings (i.e. shoemakers' tools and supplies) business. Dave Tandy had a son, Charles David Tandy , who was drafted into the business during his early twenties. Charles obtained a B.A. degree at Texas Christian University , then began attending

8989-526: The system, with the latter proving to be justified, the technology having been "announced... heavily promoted; then it was delayed, and finally, it just never appeared". A standard CD-R is a 1.2 mm (0.047 in) thick disc made of polycarbonate about 120 mm (5") in diameter. The 120 mm (5") disc has a storage capacity of 74 minutes of audio or 650 Megabytes (MBs) of data. CD-R/RWs are available with capacities of 80 minutes of audio or 737,280,000 bytes (700 MB), which they achieve by molding

9090-531: The third error correction layer defined in the Yellow Book. Properly written CD-R discs on blanks of less than 80 minutes in length are fully compatible with the audio CD and CD-ROM standards in all details including physical specifications. 80-minute CD-R discs marginally violate the Red Book physical format specifications, and longer discs are non-compliant. CD-RW discs have lower reflectivity than CD-R or pressed (non-writable) CDs and for this reason cannot meet

9191-516: The unwary lower-income people". A BYTE reviewer admitted in 1983 that he at first dismissed the Model 100 "as a toy" because he saw it in a store next to a radio-controlled car , stating that "it's too bad that Radio Shack is associated with toys and CB radio " when the computer "shows tremendous planning and foresight". In 1984, a sell-side analyst stated that Tandy had an "impressive product line, magnificent distribution capability, control of

9292-583: The use of the term CD-WO in favor of CD-R , while CD-MO was rarely used. Written CD-Rs and CD-RWs are, in the aspect of low-level encoding and data format, fully compatible with the audio CD ( Red Book CD-DA ) and data CD ( Yellow Book CD-ROM ) standards. The Yellow Book standard for CD-ROM only specifies a high-level data format and refers to the Red Book for all physical format and low-level code details, such as track pitch, linear bit density, and bitstream encoding. This means they use Eight-to-Fourteen Modulation , CIRC error correction, and, for CD-ROM ,

9393-411: The whole process from manufacturing through distribution, and a reasonably nimble management that is willing to move with the product cycle". That year, Tandy was the leading Unix vendor by volume, selling almost 40,000 units of the 68000 -based, multiuser Tandy Model 16 with Xenix , and began selling all computers using the Tandy brand because, an executive admitted, "we were told by customers that

9494-464: Was CDRM Recordable Media. With quality technical media being limited from Taiyo Yuden , Early CD-R Media used Phthalocyanine dye for duplication, which has a light aqua color. By 1992, the cost of typical recorders was down to $ 10,000–12,000, and in September 1995, Hewlett-Packard introduced its model 4020i manufactured by Philips, which, at $ 995, was the first recorder to cost less than $ 1000. As of

9595-443: Was a supercenter concept featuring name-brand and private label computers, software and related products; acquired in 1991, these supplanted the original Radio Shack Computer Center chain, which closed that year. Computer City became the first International Computer Superstore with over 100 locations in six countries. In 1995, Computer City was recognized as the 2nd fastest retailer to hit $ 1 (~$ 2.00 in 2023) billion in sales. In 1996, it

9696-399: Was introduced and set in the Orange Book, part 1 as a CD with a magneto-optical recording layer. The CD-MO standard allowed for an optional non-erasable zone on the disc that could be read by CD-ROM units. Data recording (and erasing) was achieved by heating the magneto-optical layer's material (e.g. Dy Fe Co or less often Tb Fe Co or Gd Fe Co ) to its Curie point and then using

9797-549: Was made using a Yamaha YPDR 601 . The concert was performed by Claudio Baglioni at the Stadio Flaminio in Rome, Italy. At that time, it was generally anticipated that recordable CDs would have a lifetime of no more than 10 years. However, as of July 2020 the CD from this live recording still plays back with no uncorrectable errors. In the same year, the first company to successfully & professionally duplicate CD-R media

9898-610: Was mailed to readers of Popular Science magazine who had responded to two-inch test ads that were placed by Tandy. From 1950 forward Tandy operated retail mail order stores supported by direct mail advertising. This successful formula helped the company expand into a chain of some 150 leathercraft stores. A growing do-it-yourself movement, prompted by a shortage of consumer goods and high labor costs, continued to gather momentum. The fifteen leathercraft stores opened during this division's first two years of operation became quite successful. Tandy began expanding by gaining new product lines;

9999-411: Was maintained so that the same catalogue number in both companies would refer to the same item. Tandy stores in the UK sold mainly own-brand goods under the 'Realistic' label and the shops were distinguished on the high street by continuing to use written sales receipts and a cash drawer instead of a till as late as the early 1990s. Staff were required to take the name and address of any customer who made

10100-535: Was purchased in 1955 by the American Hide and Leather Company of Boston, whose name changed in 1956 to General American Industries (GAI). Charles continued to maintain control of managing the Tandy Leather division while owned by GAI. During 1956, General American Industries acquired three other companies unrelated to the leather industry and a struggle for control of the parent company began. Charles saw

10201-418: Was recognized as the second fastest retailer to hit $ 2 (~$ 3.59 billion in 2023) billion in sales. (Sam's Club was the fastest retailer to hit $ 1 billion.) Alan Bush, former EVP of RadioShack and Jim Hamilton, known as the "Father of Computer Retailing," were the strategists behind the rapid growth and success. The Computer City stores were later sold to CompUSA . In 1983, Conroy sold O'Sullivan Industries,

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