Editing TRS-80 (section)

== History ==
=== Development ===
[[File:Radio Shack Tandy TRS-80 Model I System.JPG|thumb|{{nowrap|Tandy/Radio Shack TRS-80 Model I}}]]
In the mid-1970s, [[Tandy Corporation]]'s [[Radio Shack]] division was a successful American chain of more than 3,000 electronics stores. Among the Tandy employees who purchased a [[MITS Altair]] [[kit computer]] was [[purchasing agent|buyer]] Don French, who began designing his own computer and showed it to the vice president of manufacturing [[John V. Roach]], Tandy's former [[electronic data processing]] manager.<ref>obituary, ''[https://thenyledger.com/business/john-roach-pioneer-of-the-personal-computer-is-dead-at-83/ John Roach, Pioneer of the Personal Computer, Is Dead at 83]'', The New York Ledger, Business, March 24, 2022</ref><ref>[[Texas Christian University]], "John V. Roach Honors College". Archived from the original on 2018-05-27. Retrieved 2018-05-26</ref> Although the design did not impress Roach, the idea of selling a microcomputer did. When the two men visited [[National Semiconductor]] in California in mid-1976, [[Homebrew Computer Club]] member Steve Leininger's expertise on the [[SC/MP]] microprocessor impressed them. National executives refused to provide Leininger's contact information when French and Roach wanted to hire him as a consultant, but they found Leininger working part-time at [[Byte Shop]]. Leininger was unhappy at National, his wife wanted a better job, and Texas did not have a [[state income tax]]. Hired for his technical and retail experience, Leininger began working with French in June 1976. The company envisioned a kit, but Leininger persuaded the others that because "too many people can't solder", a preassembled computer would be better.<ref name="swaine19810831"/>{{r|thomas1977}}{{r|white198708}}{{r|reed1}}

Tandy had 11 million customers that might buy a microcomputer, but it would be much more expensive than the {{US$|30}} median price of a Radio Shack product, and a great risk for the very conservative company.<ref name="reed1">{{cite web |url=http://www.trs-80.org/trs80-introduction-part1/ |title=The Introduction of the TRS‑80 (Part 1) |publisher=TRS-80.org |access-date=January 23, 2015 |author=Reed, Matthew}}</ref>{{r|white198708}} Executives feared losing money as [[Sears]] did with [[Cartrivision]],<ref name="leininger19770917">{{cite conference |url=http://www.trs-80.com/trs80-models-model1.htm |title=TRS-80 architect reminisces about design project |access-date=February 28, 2011 |author=Leininger, Steven W. |date=September 1977 |conference=San Diego Computer Society |archive-date=May 31, 2012 |archive-url=https://web.archive.org/web/20120531175602/http://www.trs-80.com/trs80-models-model1.htm |url-status=dead}}</ref> and many opposed the project; one executive told French, "Don't waste my time—we can't sell computers." As the popularity of [[Citizens band radio|CB radio]]—at one point comprising more than 20% of Radio Shack's sales—declined, however, the company sought new products. In December 1976 French and Leininger received official approval for the project but were told to emphasize cost savings; for example, leaving out lowercase characters saved US$1.50 in components and reduced the retail price by {{US$|5}}. The original {{US$|199}} retail price required [[manufacturing cost]] of {{US$|80}}; the first design had a [[membrane keyboard]] and no video monitor. Leininger persuaded Roach and French to include a better keyboard, a monitor, [[datacassette]] storage, and other features requiring a higher retail price to provide Tandy's typical profit margin. In February 1977 they showed their prototype, running a simple tax-accounting program, to [[Charles Tandy]], head of Tandy Corporation. The program quickly crashed as the computer's implementation of [[Tiny BASIC]] could not handle the {{US$|150,000}} figure that Tandy typed in as his salary, and the two men added support for [[floating-point math]] to its [[Level I BASIC]] to prevent a recurrence. The project was formally approved on 2 February 1977; Tandy revealed that he had already leaked the computer's existence to the press. When first inspecting the prototype, he remarked that even if it did not sell, the project could be worthy if only for the publicity it might generate.{{r|ahl198411}}<ref name="white198708">{{Cite magazine |last=White |first=Ron |date=August 1987 |title=The Tandy Story: It all started 10 years ago in a converted used-car showroom... |url=https://archive.org/details/80-microcomputing-magazine-1987-08/page/n51 |magazine=[[80 Micro]] |pages=50–64 |access-date=2019-05-18}}</ref>{{r|reed1}}

MITS sold 1,000 Altairs in February 1975 and was selling 10,000 a year. When Charles Tandy asked who would buy the computer, company president Lewis Kornfeld admitted that they did not know if anyone would, but suggested that small businesses and schools might. Knowing that demand was very strong for the {{US$|795}} Altair—which cost more than $1,000 with a monitor—Leininger suggested that Radio Shack could sell 50,000 computers,<ref name="reed2">{{cite web |url=http://www.trs-80.org/trs80-introduction-part2/ |title=The Introduction of the TRS‑80 (Part 2) |publisher=TRS-80.org |access-date=January 23, 2015 |author=Reed, Matthew}}</ref>{{r|white198708}} but no one else believed him; Roach called the figure "horseshit", as the company had never sold that many of anything at that price. Roach and Kornfeld suggested 1,000 to 3,000 per year; 3,000 was the quantity the company would have to produce to buy the components in bulk. Roach persuaded Tandy to agree to build 3,500—the number of Radio Shack stores—so that each store could use a computer for inventory purposes if they did not sell.<ref name="welch2007"/><ref name="swaine19810831">{{cite magazine |url=https://books.google.com/books?id=rD0EAAAAMBAJ&pg=PA40 |title=How the TRS-80 Was Born |access-date=February 28, 2011 |first=Michael |last=Swaine  |author-link=Michael Swaine (technical author) |date=August 31, 1981 |magazine=[[InfoWorld]] |pages=40–43 |volume=3 |number=17}}</ref><ref name="thomas1977">{{cite news |url=https://archive.org/stream/CreativeComputingv03n05SeptOct1977/Creative_Computing_v03n05_Sept_Oct_1977#page/n93/mode/2up |title=Radio Shack's $600 Home Computer |author=Thomas, Wes |work=[[Creative Computing]] |date=September–October 1977 |pages=94–95}}</ref><ref name="ahl198411">{{cite web |url=http://www.atarimagazines.com/creative/v10n11/292_Tandy_Radio_Shack_enters_.php |title=Tandy Radio Shack enters the magic world of computers |access-date=February 26, 2011 |author=Ahl, David |author-link=David Ahl 
 |date=November 1984 |work=[[Creative Computing]] |page=292}}</ref>{{r|white198708}} [[RCA]] agreed to supply the video monitor—a black-and-white television with the tuner and speakers removed—after others refused because of Tandy's low initial volume of production. Tandy used the black-and-silver colors of the RCA CRT unit's cabinet for the TRS-80 units as well.{{r|white198708}}

=== Announcement ===
Having spent less than {{US$|150,000}} on development, Radio Shack announced the TRS-80 (Tandy Radio Shack) at a New York City press conference on August 3, 1977.<ref>{{cite magazine |archive-url=https://web.archive.org/web/20150803160213/https://time.com/3968790/tandy-trs-80-history/ |archive-date=3 August 2015 |url=https://time.com/3968790/tandy-trs-80-history/ |title=The Personal Computer That Beat Apple (For a While) |first=Lile |last=Rothman |magazine=[[Time (magazine)|Time]]}}</ref> It cost {{US$|399}} ({{Inflation|US|399|1977|r=-2|fmt=eq}}), or {{US$|599}} ({{Inflation|US|599|1977|r=-2|fmt=eq}}) with a 12" monitor and a Radio Shack tape recorder; the most expensive product Radio Shack previously sold was a {{US$|500}} stereo. The company hoped that the new computer would help Radio Shack sell higher-priced products, and improve its "schlocky" image among customers. Small businesses were the primary target market, followed by educators, then consumers and hobbyists; despite its hobbyist customer base, Radio Shack saw them as "not the mainstream of the business" and "never our large market".{{r|thomas1977}}{{r|brown198001}}{{r|reed2}}<ref name="freibergerfuture19810831">{{cite magazine |url=https://books.google.com/books?id=rD0EAAAAMBAJ&pg=PA49 |title=Radio Shack Prepares for the Future |magazine=[[InfoWorld]] |date=31 August 1981 |volume=3 |number=17 |access-date=26 October 2016 |author=Freiberger, Paul |author-link=Paul Freiberger  |pages=51, 53–54}}</ref>{{r|bartimo19840820}}{{r|white198708}}

Although the press conference did not receive much media attention because of [[Fuerzas Armadas de Liberación Nacional Puertorriqueña#Major incidents|a terrorist bombing elsewhere in the city]], the computer received much more publicity at [[Boston University]]'s Personal Computer Fair two days later.<ref>{{cite journal |title=Computer fair comes to Boston |journal=Personal Computing Magazine |date=1 May 1977 |url=https://archive.org/details/PersonalComputing19770506/page/n13/mode/1up |access-date=7 March 2021 |quote=If you are going to be anywhere all the computer buffs from near Boston on August 4th, 5th or 6th, you may want to get over to Boston University. They are going to have a PERSONAL COMPUTING show complete with exhibits, seminars and everything that's new and up to date that you can see, touch, feel and play with in home computing. And just because Boston suburbia has more colleges and universities per square foot than any other region of the United States doesn't mean that this computing show is just for high school, college students and their professors. To be sure, MIT, Tufts, Harvard, Boston College, Brandeis, Emerson, Simmons, Northeastern, Babson, University of Massachusetts, Bentley, Wentworth, Lincoln, Emmanuel, Lesley, Curry, Radcliff, Jackson, Suffolk, Wheelock and so forth will be there. B.U. is organizing the fair to be of interest for everybody in personal computing.}}</ref>{{r|bartimo19840820}}{{r|brown198001}}<ref>[http://www.latinamericanstudies.org/puertorico/sep4.htm Clinton Pardons Terror]. ''[[New York Post]]''. 1999-08-13. Retrieved 2017-08-03.</ref>{{r|ap19770806}}{{r|freibergerfuture19810831}}{{r|fylstra197804}}<ref>Pérez, Gina M. (2005). [http://www.encyclopedia.chicagohistory.org/pages/489.html Fuerzas Armadas de Liberación Nacional (FALN)]. Encyclopedia of Chicago. Chicago Historical Society.</ref>{{r|reed2}}{{r|thomas1977}}{{r|welch2007}}<ref>{{cite web |title=Blast from the Computer's Past |url=https://wtcomputers.com/2017/08/blast-computers-past/ |website=World Technology Computer Repair and Service |publisher=World Technology, LLC |access-date=7 March 2021 |date=3 August 2017}}</ref><ref>{{cite web |title=Introduction of the TRS-80 at the Boston Personal Computer Faire in 1977. (Photo) |url=http://forums.lawrencehageman.com/media/introduction-of-the-trs-80-at-the-boston-personal-computer-faire-in-1977.510/ |website=Lawrence Hageman Forums |access-date=7 March 2021}}</ref> {{Excessive citations inline|date=September 2021}} A front-page [[Associated Press]] article discussed the novelty of a large consumer-electronics company selling a home computer that could "do a payroll for up to 15 people in a small business, teach children mathematics, store your favorite recipes or keep track of an investment portfolio. It can also play cards." Six sacks of mail arrived at Tandy headquarters asking about the computer, over 15,000 people called to purchase a TRS-80—paralyzing the company switchboard—and 250,000 joined the waiting list with a $100 deposit.{{r|thomas1977}}{{r|welch2007}}{{r|reed2}}<ref name="ap19770806">{{cite news |url=https://news.google.com/newspapers?id=cVlNAAAAIBAJ&pg=1649%2C1159626 |title=Computers May Soon Be In Homes |work=[[Lakeland Ledger]] |date=August 6, 1977 |agency=Associated Press |access-date=January 23, 2015 |pages=1A}}</ref>{{r|fylstra197804}}{{r|white198708}}{{Excessive citations inline|date=September 2021}}

Despite the internal skepticism, Radio Shack aggressively entered the market. The company advertised "''The $599 personal computer''" as "the most important, useful, exciting, electronic product of our time".<ref name="rs19780526">{{cite news |url=https://www.newspapers.com/clip/3365536// |title=To the Doctor, the Lawyer, the Butcher, the Baker, the Candlestick Maker, and Everyone Else |work=[[The Galveston Daily News]] |date=1978-05-26 |access-date=6 October 2015 |pages=3–A |type=advertisement}}</ref> Kornfeld stated when announcing the TRS-80, "This device is inevitably in the future of everyone in the civilized world—in some way—now and so far as ahead as one can think", and Tandy's 1977 [[annual report]] called the computer "probably the most important product we've ever built in a company factory". Unlike competitor [[Commodore International|Commodore]]—which had announced the [[Commodore PET|PET]] several months earlier but had not yet shipped any—Tandy had its own factories (capable of producing 18,000 computers a month) and distribution network, and even small towns had Radio Shack stores. The company announced plans to be selling by Christmas a range of peripherals and software for the TRS-80, began shipping computers by September, opened its first computer-only store in October, and delivered 5,000 computers to customers by December. Still forecasting 3,000 sales a year, Radio Shack sold over 10,000 TRS-80s in its first one and a half months of sales, 55,000 in its first year, and over 200,000 during the product's lifetime;{{r|fylstra197804}}{{r|swaine19810831}}<ref name="hogan19810831">{{cite magazine |url=https://books.google.com/books?id=rD0EAAAAMBAJ&pg=PA44 |title=A Look at Radio Shack's Five Computers |access-date=February 28, 2011 |author=Hogan, Thom |date=August 31, 1981 |magazine=[[InfoWorld]] |volume=3 |number=17 |pages=44–45}}</ref>{{r|thomas1977}}{{r|ahl198411}}{{r|welch2007}}<ref name="bartimo19840820"/>{{r|leininger19770917}}<ref name="rscat1977">{{cite book |title=1977 TRS-80 Radio Shack Introduction Brochure |year=1977 |url=http://www.radioshackcatalogs.com/catalogs_extra/1977_rsc-01/ |publisher=Radio Shack |access-date=March 14, 2011 |archive-date=July 15, 2011 |archive-url=https://web.archive.org/web/20110715145146/http://www.radioshackcatalogs.com/catalogs_extra/1977_rsc-01/ |url-status=dead}}</ref>{{rp|4}}<ref name="brown198001">{{cite news |url=https://archive.org/stream/80-microcomputing-magazine-1980-01/80Microcomputing_0180#page/n27/mode/2up |title=The Tandy Story |access-date=October 17, 2013 |author=Brown, Chris |date=January 1980 |work=[[80 Micro]]computing |pages=28–30}}</ref>{{r|white198708}}{{Excessive citations inline|date=September 2021}} one entered the [[Smithsonian Institution|Smithsonian]]'s [[National Museum of American History]].<ref name="righthand20100803">{{cite news |url=http://www.smithsonianmag.com/smithsonian-institution/august-3-1977-the-trs-80-personal-computer-goes-on-sale-186379/ |title=August 3, 1977: The TRS-80 Personal Computer Goes on Sale |work=Smithsonian |date=August 3, 2010 |access-date=January 23, 2015 |author=Righthand, Jess}}</ref> By mid-1978 the waits of two months or more for delivery were over,<ref name="baker19780428">{{cite news |url=https://www.newspapers.com/clip/3365595// |title=Microcomputer stirs interest |work=[[The San Bernardino County Sun]] |date=1978-04-28 |access-date=6 October 2015 |author=Baker, Joe |pages=B-19}}</ref> and the company could state in advertisements that TRS-80 was "on demonstration and available ''from stock now'' at every Radio Shack store in this community!"{{r|rs19780526}}

[[File:Home or Personal Computers from 1977 - Commodore PET 2001, Apple II, TRS-80 Model I, together called 'Trinity77' (edited image).jpg|thumb|upright=1.25|''Byte''{{'}}s "1977 trinity": Commodore PET, Apple II, and TRS-80 Model I]]

=== Delivery ===
The first units, ordered unseen, were delivered in November 1977, and rolled out to the stores the third week of December. The line won popularity with hobbyists, home users, and small businesses. Tandy Corporation's leading position<ref>{{Cite web|url=http://www.computinghistory.org.uk/det/22784/TRS-80-Microcomputer-System-Model-I-16k-Level-II/|title=TRS-80 Microcomputer System Model I 16k Level II - Computer - Computing History|website=www.computinghistory.org.uk}}</ref> in what [[Byte (magazine)|''Byte'']] magazine called the "1977 Trinity" ([[Apple Computer]], [[Commodore International|Commodore]], and Tandy) had much to do with Tandy's retailing the computer through more than 3,000 of its Radio Shack storefronts in the USA.<ref name="byte95">{{cite magazine |url=http://www.byte.com/art/9509/sec7/art15.htm |title=Most Important Companies |access-date=June 10, 2008 |date=September 1995 |magazine=[[Byte (magazine)|Byte]] |url-status=dead |archive-url=https://web.archive.org/web/20080618072507/http://www.byte.com/art/9509/sec7/art15.htm |archive-date=June 18, 2008 |df=mdy-all}}</ref> Tandy claimed it had "7000 [Radio Shack] stores in 40 countries".<ref name="Tandy/Radio Shack">{{cite web|title=Radio Shack Computer Catalog RSC-3, page 24|url=https://www.radioshackcatalogs.com/flipbook/c1979_rsc-03.html?fb3d-page=24|website=Radio Shack Catalogs dot com|publisher=Tandy/Radio Shack|access-date=December 1, 2022|archive-date=May 31, 2017|archive-url=https://web.archive.org/web/20170531195020/http://www.radioshackcatalogs.com/html/catalogs_extra/1979_rsc-03/h024.html|url-status=dead}}</ref> The pre-release price for the basic system (CPU/keyboard and video monitor) was {{US$|500}} and a {{US$|50}} deposit was required, with a money-back guarantee at time of delivery.

By 1978, Tandy/Radio Shack promoted itself as "The Biggest Name in Little Computers".<ref>{{cite web|title=Radio Shack Computer Catalog RSC-2, page 20|url=https://www.radioshackcatalogs.com/flipbook/c1978_rsc-02.html?fb3d-page=20|website=Radio Shack Catalogs dot com|publisher=Tandy/Radio Shack|access-date=December 1, 2022}}</ref><ref name="Tandy/Radio Shack"/> By 1979 1,600 employees built computers in six factories.{{r|white198708}} ''[[Kilobaud Microcomputing]]'' estimated in 1980 that Tandy was selling three times as many computers as [[Apple Inc.|Apple Computer]], with both companies ahead of Commodore.<ref name="green198010">{{cite news |url=https://archive.org/stream/kilobaudmagazine-1980-10/Kilobaud_Microcomputing_1980_October#page/n5/mode/2up |title=Publisher's Remarks |work=Kilobaud Microcomputing |date=October 1980 |access-date=June 23, 2014 |author=Green, Wayne |author-link=Wayne Green |pages=6–9}}</ref> By 1981, ''[[InfoWorld]]'' described Radio Shack as "the dominant supplier of small computers".<ref name="hoganmarket19810831">{{cite magazine |url=https://books.google.com/books?id=rD0EAAAAMBAJ&pg=PA6 |title=From Zero to a Billion in Five Years |magazine=[[InfoWorld]] |volume=3 |number=17 |date=August 31, 1981 |access-date=February 15, 2015 |author=Hogan, Thom |pages=6–7}}</ref> Hundreds of small companies produced TRS-80 software and accessories,<ref name="lundell19810831">{{cite magazine |url=https://books.google.com/books?id=rD0EAAAAMBAJ&pg=PA46 |title=TRS-80 Outcrop Companies Evolve |magazine=[[InfoWorld]] |volume=3 |number=17 |date=August 31, 1981 |access-date=February 15, 2015 |author=Lundell, Allan |pages=46–47}}</ref> and [[Adam Osborne]] described Tandy as "the number-one microcomputer manufacturer" despite having "so few roots in microcomputing".<ref name="osborne19810413">{{cite magazine |last=Osborne |first=Adam |author-link=Adam Osborne |date=April 13, 1981 |url=https://books.google.com/books?id=Dj4EAAAAMBAJ&pg=PA42 |title=The Portable Osborne |magazine=[[InfoWorld]] |volume=3 |number=17 |access-date=January 1, 2015 |pages=42–43}}</ref> That year Leininger left his job as director for advanced research; French had left to found a software company,<ref name="markoff19811005">{{Cite magazine |last=Markoff |first=John |author-link=John Markoff |date=1981-10-05 |title=TRS-80 Co-creator to Leave Tandy |url=https://books.google.com/books?id=JT0EAAAAMBAJ&pg=PA3 |magazine=[[InfoWorld]] |volume=3 |issue=20 |pages=1, 6 |access-date=2020-03-20}}</ref> and the company had rejected his attempt for a Tandy Computer Center to sell non-Tandy computers.{{r|green198108}} while the company's computer success helped Roach become Tandy's CEO.<ref name="hayes19921027">{{Cite news |last=Hayes |first=Thomas C. |date=1992-10-27 |title=Tandy Ventures Into the Unknown |url=https://www.nytimes.com/1992/10/27/business/tandy-ventures-into-the-unknown.html |access-date=2024-01-09 |work=The New York Times |pages=D1 |language=en-US |issn=0362-4331}}</ref> Selling computers did not change the company's "schlocky" image; the Radio Shack name embarrassed business customers, and Tandy executives disliked the "Trash-80" nickname for its products. By 1984, computers accounted for 35% of sales, however, and the company had 500 Tandy Radio Shack Computer Centers.{{r|swaine19810831}}{{r|ahl198411}}<ref name="bartimo19840820">{{cite magazine |last=Bartimo |first=Jim |date=August 20, 1984 |url=https://books.google.com/books?id=HS8EAAAAMBAJ&pg=PA47 |title=Radio Shack Polishes Its Image |access-date=February 28, 2011 |magazine=[[InfoWorld]] |volume=6 |issue=34 |pages=47–52}}</ref>{{r|white198708}}<ref name="roachbio">{{cite web |url=http://www.ce.org/Events/Awards/2728.htm |title=John Roach, Tandy/Radio Shack |access-date=February 26, 2011 |archive-url=https://web.archive.org/web/20070709114606/http://www.ce.org/Events/Awards/2728.htm |archive-date=July 9, 2007 |publisher=Consumer Electronics Association}}</ref>

=== Model II and III ===
By 1979, when Radio Shack launched the business-oriented, and incompatible, [[TRS-80 Model II]], the TRS-80 was officially renamed the TRS-80 Model I to distinguish the two product lines.

After some exhibitors at the 1979 Northeast Computer Show were forced to clarify that their products bearing the TRS-80 name were not affiliated with Radio Shack, publications and advertisers briefly began to use "S-80" generically rather than "TRS-80" under scare of legal action, though this never materialized.<ref name="reed s80">{{cite web |url=http://www.trs-80.org/what-does-s-80-mean/ |website=TRS-80.org  |title=What does S-80 mean? |access-date=February 26, 2020 |author=Reed, Matthew}}</ref>

Following the Model III launch in mid-1980, Tandy stated that the Model I was still sold,<ref name="newsletter_8009">{{cite web |url=https://archive.org/stream/TRS-80_Microcomputer_News_Volume_2_Issue_07_1980-09_Radio_Shack_US/TRS-80_Microcomputer_News_Volume_2_Issue_07_1980-09_Radio_Shack_US_djvu.txt|quote=First of all the Model I is not dropped, it is in the 1981 Radio Shack Annual catalog and the price is unchanged.|date=September 1980|access-date=2015-03-07|title=TRS-80 Microcomputer News}}</ref> but it was discontinued by the end of the year. Tandy cited one of the main reasons as being the prohibitive cost of redesigning it to meet stricter [[Federal Communications Commission|FCC]] regulations covering the significant levels of [[Electromagnetic interference|radio-frequency interference]] emitted by the original design.<ref name="REFOldComputerOrg"/><ref name="newsletter_8101">{{cite web |url=https://archive.org/stream/TRS-80_Microcomputer_News_Volume_3_Issue_01_1981-01_Radio_Shack_US/TRS-80_Microcomputer_News_Volume_3_Issue_01_1981-01_Radio_Shack_US_djvu.txt|title=TRS-80 Microcomputer News|date=January 1981|quote=[In November we] announced that manufacturing of the Model I computer would stop prior to the end of 1980 [primarily because] to meet the new FCC regulations we would have had to redesign the entire product, case and all [which would have made] the cost of the Model I as much as the Model III|access-date=2015-03-07}}</ref> The Model I radiated so much interference that, while playing games, an [[Amplitude modulation|AM]] radio placed next to the computer can be used to provide sounds.<ref name=AMRADIODigiBarn>{{cite web| url=http://www.digibarn.com/collections/systems/trs80-model3/index.html|title=TRS-80 Model III (Tandy/Radio Shack TRS-80 Model III) |work=DigiBarn Computer Museum |access-date=July 20, 2010 |url-status=live |archive-url=https://web.archive.org/web/20100727172325/http://www.digibarn.com/collections/systems/trs80-model3/index.html |archive-date= Jul 27, 2010 }}</ref> Radio Shack offered upgrades (double-density floppy controller, LDOS, memory, reliable keyboard with numeric keypad, lowercase, Level II, RS-232C) as late as its 1984 catalog.<ref>{{Cite web |title=1984 Radio Shack TRS-80 Computer Catalog |url=https://www.radioshackcatalogs.com/flipbook/c1984_rsc-10.html?fb3d-page=27 |access-date=November 30, 2022 |website=Radio Shack Catalogs |page=27}}</ref>