Telidon
Encyclopedia
Telidon was a videotex
/teletext
service developed by the Canadian Communications Research Centre (CRC) during the late 1970s and early 1980s. The CRC referred to Telidon as a "second generation" system, offering improved performance, 2D color graphics, multi-lingual support and a number of different interactivity options supported on various hardware. With additional features added by AT&T
, Telidon became the basis for the NAPLPS
standard.
In multiple tests, Telidon failed to demonstrate compelling functionality and the equipment costs remained high. Government support for the project officially ended on 31 March 1985, and the various commercial services based on it closed shortly thereafter. Telidon saw limited use after that, in niches like informational displays in airports and similar environments. NAPLPS did appear in several other products, notably the Prodigy online service and some bulletin board
s. Telidon had a more lasting legacy on the hardware side; its NABTS
communications system found re-use years later in WebTV for Windows.
field since the late 1960s, originally using plotter
s but later moving to video systems. Starting in 1970, Bown and a team at the CRC started working on a "Picture Description Instruction" (PDI) format to encode vector graphics
information. An interpreter, the "Interactive Graphics Programming Language" (IGPL), read the PDI codes and rasterized them for display. By this time the team consisted of Bown, Doug O'Brien, Bill Sawchuck, J.R. Storey and Bob Warburton.
As the work continued, the team decided that locking the system to the particular hardware they were using was not appropriate, and started modifying the PDI system to be based on alpha-numeric codes instead of binary numbers. A major advantage to this approach is that the data can be sent over common communications channels instead of relying on an 8-bit clean
link to the host computer. In 1975 the CRC contracted Norpak
to develop an interactive color display terminal based on the new alpha-numeric PDI. The CRC had patented several of the technologies by the end of 1977; a touch-sensitive input mechanism, the basic graphics system, and the interactive graphics programming language.
By the mid-1970s several European countries were in the process of introducing videotex and teletext services. There was considerable interest within the industry, and in the media, suggesting that online services would be the "next big thing". Comments to the effect that "Within the next few decades, people may be able to access much of the published information in the world from their living rooms by using videotex," were common in the trade press.
The CRC was able to interest the Department of Communications (DoC), their superiors within the federal government, to fund development of their system into the basis for a videotex service. Unlike the systems being developed in Europe, the new system would offer high-quality 2D graphics, and could be used for one-way fixed or menued displays (teletext), two-way systems based on modem
s (videotex), or they could combine the two, allowing information to be sent to the customer in the video signal, and returned via modem.
) held a press conference and formally announced the Telidon project to the public, demonstrating a large video display sending information to the minicomputer
controlling it over an acoustic coupler
modem
. They outlined a four-year development plan that included funding for further technical development at the CRC, the production of several hundred terminals that would be lent out to industry for development studies, as well as funds for marketing and lobbying in videotex standards negotiations.
In 1979 the DoC formed the Canadian Videotex Consultative Committee to advise the Minister on ways to commercialize the CRC's work, and develop videotext services within Canada. The committee held four meetings during the initial four-year development plan, and coordinated a number of field trials with broadcasters, telephone companies, cable television
firms, manufacturers and various information providers. During the same period, the Task Force on Service to the Public was given the job of using Telidon as a way to provide public access to government information and services.
By late 1979 Norpak had developed a version of the Telidon decoder that was housed in a box about the size of a modern digital cable
set top box. A menu selection keyset, about the size and shape of a contemporary calculator
, connected to it using a ribbon cable
. With the hardware in place, the CRC started working with telecommunications providers to test the system in production settings. Many of the major Canadian carriers expressed strong interest, and a number of test systems were ready to roll out by the early 1980s. Excitement was high; the 19 November 1981 issue of the Globe and Mail said that "Telidon may become as commonly used as the telephone and will have just as great a social impact, a representative of the Videotex Consultative Committee told the Canadian Computer Show and Conference in Toronto."
In a radio broadcast in 1980, Douglas Parkhill
, the deputy minister of research at the DoC outlined some of the potential uses, from financial information, to theatre reservations, with the ability to pay and print out tickets from the system.
, just west of Winnipeg
, part of an experimental system being deployed by the Manitoba Telephone System (MTS), the local cable operator.
Named for Ida Cates, Manitoba's first woman telephone operator in the 1880s, "Project Ida" was part of a wider rollout of advanced cable technologies that MTS had been planning since 1978 to study ways to use up the bandwidth capabilities of newer cable systems. Services included Telidon, cable telephony
, pay tv
service using outdoor converters (instead of set top boxes), and low-bandwidth backchannel data services for gas and electrical billing and alarm services. The Telidon services that formed part of Project Ida were created by Infomart, a Toronto
-based company set up to provide Telidon content. It was hosted on two computers set up in Winnipeg and run by MTS, providing a 4800 baud channel to the in-home terminals. Originally scheduled for January 1980, delays pushed this back to mid-year. Ida ran until 1981, when most of the services were dropped and the cables returned to normal analog signals, although an off-shoot using optical cable was carried out in Elie
, rotating the terminals though many households in the area.
Ida was followed by a flood of Canadian companies starting similar projects. In early 1980, TVOntario
, the educational television channel run by the Ontario government, set up 45 terminals in the Toronto area. In April 1981, New Brunswick Telephone
set up a system practically identical to Project Ida with a full suite of services, with somewhere between 20 and 100 terminals. The same month, Alberta Government Telephones
started "Project VIDON", a smaller modem-based test in the Calgary
area. A month later, Bell Canada
announced their "Vista" project in Toronto and Montreal, in partnership with the Toronto Star
and the Southam Press
who would provide content. This test eventually expanded to between 500 and 1000 terminals.
Telidon generated interest outside Canada as well. A major foreign sale was made in July 1980 to the government of Venezuela, who set up a test system to provide information on health, social and economic aid programs to the vast numbers of people moving into Caracas
from rural areas.
A number of U.S. companies also expressed an interest, and started plans to roll out their own Telidon-based teletext systems. As early as 1978, AT&T
and CBS
had been experimenting with the idea of a videotex service, and were drawn towards the Telidon efforts. In 1982 they rolled out an experimental system known as "Venture One" in Ridgewood, New Jersey
, equipping some homes with stand-alone terminals from AT&T, and others with set-top boxes. The test ran for seven months from 1982 to 83, and was considered a success, so much so that AT&T publicly announced plans to introduce a commercial system in 1984.
was so impressed with the Telidon that they started a standardization effort with Bell and the DoC. AT&T contributed two major additions to the system; the ability to define your own character sets, and the ability to wrap up multiple graphics commands into a "macro". The former provided for the creation of small graphics that could be sent with a low transmission cost, which is useful in certain roles where the graphics can be arranged in a grid, like a chessboard. The later allowed the programmers to create a commonly used graphical element, the AT&T logo for instance, and save it to a macro. The graphic can then be re-created with a single instruction in any page that needed it.
The resulting system emerged in 1983 as NAPLPS
, while the transmission method that encoded information into the vertical blank interrupt
of a TV signal became the NABTS
standard. Major articles in Byte Magazine introduced the NAPLPS system to a wider audience, spread over a four month period in the February, March, April, and May 1983 issues.With the standard complete, the U.S. teletext plans started moving forward. NAPLPS' ability to draw complex graphics was particularly interesting to U.S. vendors, as it allowed them to draw network or advertiser logos.
By this point the technical development of Telidon was complete, and that portion of the Canadian government's involvement wound down in the summer of 1983. Further efforts were aimed at helping develop a commercial marketplace for Telidon systems and content, running for another year.
s instead of cable links and was aimed specifically at farmers, providing a number of weather reports and other information, as well as optional links to live commodities pricing on various exchanges. Prices were high: in addition to purchasing a terminal there was an additional one-time $100 set-up fee, the annual fee was $150, and there was a $19.00/hr charge to connect to the service, and another $6.00/hr for "communications". Nevertheless, Grassroots grew into a system that distributed 20,000 pages of information to farmers created by Infomart. Based in Winnipeg
, Grassroots expanded to serve Alberta
, Saskatchewan
, northern Ontario
, and in 1985, the northern United States
.
A major effort to introduce Telidon in a public setting was the NABU Network
. Unlike traditional Telidon systems, NABU terminals were complete home computer
s in their own right, using the Zilog Z80
CPU and running a CP/M
clone, but booting and launching programs over the cable modem
. It launched with about 100 programs, mostly games, but also including personal finance packages and such, as well as using Telidon for online banking and other consumer services. Users bought the hardware for $950 and connected it to their color television, accessing programs via cable for $8 to $10 per month. After the official launch on Ottawa Cablevision in October of 1983, the NABU Network was introduced by Ottawa's Skyline Cablevision in 1984 and a year later in Sowa, Japan, via a collaboration between NABU and ASCII Corp
. NABU machines used Telidon for online banking and other services.
A significant showcase for the Telidon system was set up for the Third General Assembly of the Inuit Circumpolar Council, hosted in Frobisher Bay
on Baffin Island
in July 1983. A database of information about the conference and its services was hosted by Teleglobe Canada in Toronto
on their Novatex system, with the information translated into English, French, Danish, Inuktitut, Greenlandic, Labradorian, Inupiag, Yupik and Western Arctic. Sixteen Telidon terminals, supplied by Microtel, were located at various sites in Frobisher Bay, with additional terminals in Vancouver
, Washington D.C., Copenhagen
, Anchorage, Bethel
, Barrow
, Nuuk
, as well as other northern communities. Communications were provided by Bell Canada
, Teleglobe
, Greenland Telecommunications and the Danish Post and Telegraph
.
The Canadian government also invested in Telidon as a way of distributing graphical information. Transport Canada
ran a system called "TABS" that installed terminals in many airports, where pilots could quickly look up weather information and NOTAM
s. Statistics Canada
also used Telidon as a way to distribute graphs and other information in their CANSIM system using their TELICHART software that converted tables of data into NAPLPS commands. Environment Canada
used Telidon terminals to produce video feeds that could then be broadcast on local cable feeds.
In the Toronto area, "Teleguide" terminals were common fixtures at larger shopping malls, government buildings (e.g. Scarborough Civic Centre
) and notably the Toronto Eaton Centre
. Run by London, Ontario
's Cableshare, the system relied on an 8085-based microcomputer which drove several NAPLPS terminals fitted with touch screens, all communicating via Datapac
to a back-end database. The system offered news, weather and sports information along with shopping mall guides and coupons. Rollouts were announced in several other cites as well.
The largest efforts were made in the United States. After the Venture One experiments in 1982/3, AT&T decided not to pursue a videotex service of its own, but instead provide service and support to other companies who wanted to. CBS
invested considerable capital in the development of their ExtraVision
service, which also included closed captioning
and channel information along with more traditional Telidon information. Affiliate stations could also insert their own content into the streams, although the high cost of the systems needed to do this made it relatively rare.
AT&T also partnered with Knight-Ridder Newspapers to form Viewdata, a holding company that operated the "Viewtron
" service. Test marketed in Florida in 1980, the service expanded to the entire southern Florida area by 1983, and then expanded to much of the eastern seaboard. Viewdata started primarily as a news service, but over time included more and more features. As it operated over modems in a pure videotex format, it was able to offer a variety of two-way services including e-mail and bulletin boards. A similar system was "Gateway", run by AT&T and the Los Angeles Times
.
In 1984 Tribune Media Services
(TMS) and the Associated Press
operated a cable television channel called "AP News Plus" that provided NAPLPS-based news screens to cable television subscribers in many U.S. cities. The news pages were created and edited by TMS staffers working on an Atex editing system in Orlando, Florida, and sent by satellite to NAPLPS decoder devices located at the local cable television companies. The images were rendered locally, and then sent out as normal television signals to the customers. This avoided the need to send entire channels of video over satellite to the affiliate stations, instead, a small amount of data was sent and allowed the video to be re-created, for significantly less cost.
Most teletext systems, Telidon included, were created in the context of the broadcast model, where the content would be provided by large vendors and then pushed one-way to the user in a fashion similar to television or newspapers. Interactivity was generally limited to menu selections or providing information on forms (like online banking
). This placed the entire burden of creating the content on the service providers and their partners, an expensive and time-consuming process. Since much of the content in question was already available on different media controlled by the same companies, teletext services also had the problem of competing with encumbent mediums that were less expensive and better developed.
Telidon was also expensive. When it was introduced the DoC expected terminals to be available for $200 to $300 by 1982, but this did not come to be. The largest suppliers of terminals were Electrohome
, Norpak and Microtel, whose terminals ranged between $1,800 and $2,500. During the development period the hardware manufacturers felt that demand would drive down prices to less than $600, however, results from trials indicated that even this would be considered too expensive for the mass market.
s with graphics capabilities similar to Telidon had already come and gone, driving prices to points far below even the simplest Telidon terminal. A second generation of machines like the Apple Macintosh, Commodore Amiga and Atari ST
were entering the market with capabilities Telidon systems could not match. At the same time, information services like CompuServe
and The Source were offering a usable online experience that Telidon failed to offer.
For all of these reasons, interest in Telidon, and Videotex in general, quickly faded. The government's funding of the Telidon efforts came to an official end on 31 March 1985, at which point $69 million had been spent. It was estimated that another $200 million had been invested by various industry partners, $100 million of that by Bell Canada. Most of the early test systems had ended their runs by 1982, while the commercial systems persevered for a few years longer; NBC
's system ended in January 1985, followed by NABU in 1985/6, and then ExtraVision, Viewtron and Gateway in March 1986. In spite of these services finding some level of consumer demand, none were able to find a pricing structure that paid for their operation while still being interesting to their consumer base.
Telidon systems continued to be used as a one-way medium for some time. A common use was to use Telidon terminals to produce video that was then broadcast for viewing, rather than the digital information itself. Systems like this were common for informational displays in airports and other public areas, as well as information displays for cable TV stations.
After Telidon was declared dead and most of the commercial efforts had ended, NAPLPS received a fresh breath of life as the basis of the Prodigy online service. In the time between efforts like Viewtron and the launch of Prodigy in 1988, personal computer
s with the ability to view NAPLPS graphics with ease had become common, and modem speeds had increased to the point where the data was no longer overwhelming. After a promising start, Prodigy management invoked a series of blunders that seriously upset their customer base, and the arrival of the World Wide Web
in the mid-1990s killed it off.
NABTS, the communications protocol for embedding data in the TV signal, also saw continued use after the Telidon project ended. It was widely used for closed captioning
support, although not the only system available. It was also used for Microsoft
's WebTV for Windows and Intel's Intercast
. Both used custom tuners, in the form of plug-in cards for PC's, that captured the information encoded into the VBI or even an entire TV channel.
For his work on Telidon, Herb Bown received the Order of Canada
and the gold medal for engineering excellence from the Association of Professional Engineers of Ontario. The Touche Ross New Perspectives Award was awarded to Herb Bown and Doug O'Brien. Bown later formed IDON Corp to develop interactive teaching materials.
Videotex
Videotex was one of the earliest implementations of an "end-user information system". From the late 1970s to mid-1980s, it was used to deliver information to a user in computer-like format, typically to be displayed on a television.In a strict definition, videotex refers to systems that provide...
/teletext
Teletext
Teletext is a television information retrieval service developed in the United Kingdom in the early 1970s. It offers a range of text-based information, typically including national, international and sporting news, weather and TV schedules...
service developed by the Canadian Communications Research Centre (CRC) during the late 1970s and early 1980s. The CRC referred to Telidon as a "second generation" system, offering improved performance, 2D color graphics, multi-lingual support and a number of different interactivity options supported on various hardware. With additional features added by AT&T
AT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
, Telidon became the basis for the NAPLPS
NAPLPS
NAPLPS is a graphics language for use originally with videotex and teletext services. NAPLPS was developed from the Telidon system developed in Canada, with a small number of additions from AT&T...
standard.
In multiple tests, Telidon failed to demonstrate compelling functionality and the equipment costs remained high. Government support for the project officially ended on 31 March 1985, and the various commercial services based on it closed shortly thereafter. Telidon saw limited use after that, in niches like informational displays in airports and similar environments. NAPLPS did appear in several other products, notably the Prodigy online service and some bulletin board
Bulletin board
A bulletin board is a surface intended for the posting of public messages, for example, to advertise things to buy or sell, announce events, or provide information...
s. Telidon had a more lasting legacy on the hardware side; its NABTS
NABTS
NABTS, the North American Broadcast Teletext Specification, is a protocol used for encoding NAPLPS-encoded teletext pages, as well as other types of digital data, within the vertical blanking interval of an analog video signal...
communications system found re-use years later in WebTV for Windows.
Genesis
Herb Bown is widely considered to be the "father" of Telidon. Bown had been working in the computer graphicsComputer graphics
Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....
field since the late 1960s, originally using plotter
Plotter
A plotter is a computer printing device for printing vector graphics. In the past, plotters were widely used in applications such as computer-aided design, though they have generally been replaced with wide-format conventional printers...
s but later moving to video systems. Starting in 1970, Bown and a team at the CRC started working on a "Picture Description Instruction" (PDI) format to encode vector graphics
Vector graphics
Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon, which are all based on mathematical expressions, to represent images in computer graphics...
information. An interpreter, the "Interactive Graphics Programming Language" (IGPL), read the PDI codes and rasterized them for display. By this time the team consisted of Bown, Doug O'Brien, Bill Sawchuck, J.R. Storey and Bob Warburton.
As the work continued, the team decided that locking the system to the particular hardware they were using was not appropriate, and started modifying the PDI system to be based on alpha-numeric codes instead of binary numbers. A major advantage to this approach is that the data can be sent over common communications channels instead of relying on an 8-bit clean
8-bit clean
8-bit clean describes a computer system that correctly handles 8-bit character sets, such as the ISO 8859 series and the UTF-8 encoding of Unicode.- History :...
link to the host computer. In 1975 the CRC contracted Norpak
Norpak
Norpak Corporation was a company headquartered in Kanata, Ontario, Canada, that specialized in the development of systems for television-based data transmission...
to develop an interactive color display terminal based on the new alpha-numeric PDI. The CRC had patented several of the technologies by the end of 1977; a touch-sensitive input mechanism, the basic graphics system, and the interactive graphics programming language.
By the mid-1970s several European countries were in the process of introducing videotex and teletext services. There was considerable interest within the industry, and in the media, suggesting that online services would be the "next big thing". Comments to the effect that "Within the next few decades, people may be able to access much of the published information in the world from their living rooms by using videotex," were common in the trade press.
The CRC was able to interest the Department of Communications (DoC), their superiors within the federal government, to fund development of their system into the basis for a videotex service. Unlike the systems being developed in Europe, the new system would offer high-quality 2D graphics, and could be used for one-way fixed or menued displays (teletext), two-way systems based on modem
Modem
A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...
s (videotex), or they could combine the two, allowing information to be sent to the customer in the video signal, and returned via modem.
Telidon development
On 15 August 1978, the DoC (whose technical side is now part of the Department of Trade and IndustryDepartment of Trade and Industry
The Department of Trade and Industry was a United Kingdom government department which was replaced with the announcement of the creation of the Department for Business, Enterprise and Regulatory Reform and the Department for Innovation, Universities and Skills on 28 June 2007.-History:The...
) held a press conference and formally announced the Telidon project to the public, demonstrating a large video display sending information to the minicomputer
Minicomputer
A minicomputer is a class of multi-user computers that lies in the middle range of the computing spectrum, in between the largest multi-user systems and the smallest single-user systems...
controlling it over an acoustic coupler
Acoustic coupler
In telecommunications, the term acoustic coupler has the following meanings:# An interface device for coupling electrical signals by acoustical means—usually into and out of a telephone instrument....
modem
Modem
A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...
. They outlined a four-year development plan that included funding for further technical development at the CRC, the production of several hundred terminals that would be lent out to industry for development studies, as well as funds for marketing and lobbying in videotex standards negotiations.
In 1979 the DoC formed the Canadian Videotex Consultative Committee to advise the Minister on ways to commercialize the CRC's work, and develop videotext services within Canada. The committee held four meetings during the initial four-year development plan, and coordinated a number of field trials with broadcasters, telephone companies, cable television
Cable television
Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...
firms, manufacturers and various information providers. During the same period, the Task Force on Service to the Public was given the job of using Telidon as a way to provide public access to government information and services.
By late 1979 Norpak had developed a version of the Telidon decoder that was housed in a box about the size of a modern digital cable
Digital cable
Digital cable is a generic term for any type of cable television distribution using digital video compression or distribution. The technology was originally developed by Motorola.-Background:...
set top box. A menu selection keyset, about the size and shape of a contemporary calculator
Calculator
An electronic calculator is a small, portable, usually inexpensive electronic device used to perform the basic operations of arithmetic. Modern calculators are more portable than most computers, though most PDAs are comparable in size to handheld calculators.The first solid-state electronic...
, connected to it using a ribbon cable
Ribbon cable
A ribbon cable is a cable with many conducting wires running parallel to each other on the same flat plane. As a result the cable is wide and flat. Its name comes from the resemblance of the cable to a piece of ribbon.Ribbon cables are usually seen for internal peripherals in computers, such as...
. With the hardware in place, the CRC started working with telecommunications providers to test the system in production settings. Many of the major Canadian carriers expressed strong interest, and a number of test systems were ready to roll out by the early 1980s. Excitement was high; the 19 November 1981 issue of the Globe and Mail said that "Telidon may become as commonly used as the telephone and will have just as great a social impact, a representative of the Videotex Consultative Committee told the Canadian Computer Show and Conference in Toronto."
It is no exaggeration to say that the telecommunications marketplace in Canada was gripped by Telidon fever from late 1979 to late 1982. Hope and belief displaced analysis and reason: hope and belief in technology -- science-based technology -- as an agent of change, a bringer of novelty, and enhancer of life. After all, there was a revolution taking place -- the communications revolution. So we were told.
In a radio broadcast in 1980, Douglas Parkhill
Douglas Parkhill
Douglas F. Parkhill is a Canadian technologist and former research minister, best known for his pioneering work on what is now called cloud computing, and his work on Canada's Telidon videotex project....
, the deputy minister of research at the DoC outlined some of the potential uses, from financial information, to theatre reservations, with the ability to pay and print out tickets from the system.
Public testing
The release of Norpac's Telidon terminal led to a rush of announcements by broadcasters and news organizations who would be rolling out test systems starting late that year. However, a variety of delays pushed back most of these programs into 1980. The race to have the first operational deployment was won by the small town of South HeadingleyHeadingley, Manitoba
Headingley is a rural municipality in Manitoba, Canada. It is located directly west of Winnipeg and has a population of 2,726 people as of the 2006 census. The Trans-Canada Highway and the Assiniboine River run through the municipality. The portion located on the south bank of the Assiniboine is...
, just west of Winnipeg
Winnipeg
Winnipeg is the capital and largest city of Manitoba, Canada, and is the primary municipality of the Winnipeg Capital Region, with more than half of Manitoba's population. It is located near the longitudinal centre of North America, at the confluence of the Red and Assiniboine Rivers .The name...
, part of an experimental system being deployed by the Manitoba Telephone System (MTS), the local cable operator.
Named for Ida Cates, Manitoba's first woman telephone operator in the 1880s, "Project Ida" was part of a wider rollout of advanced cable technologies that MTS had been planning since 1978 to study ways to use up the bandwidth capabilities of newer cable systems. Services included Telidon, cable telephony
Cable telephony
Cable telephony is a form of digital telephony over cable TV networks. A telephone interface installed at the customer's premises converts analog signals from the customer's in-home wiring to a digital signal, which is then sent over the cable connection to the company's switching center. The...
, pay tv
Pay TV
Pay television, premium television, or premium channels refers to subscription-based television services, usually provided by both analog and digital cable and satellite, but also increasingly via digital terrestrial and internet television...
service using outdoor converters (instead of set top boxes), and low-bandwidth backchannel data services for gas and electrical billing and alarm services. The Telidon services that formed part of Project Ida were created by Infomart, a Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
-based company set up to provide Telidon content. It was hosted on two computers set up in Winnipeg and run by MTS, providing a 4800 baud channel to the in-home terminals. Originally scheduled for January 1980, delays pushed this back to mid-year. Ida ran until 1981, when most of the services were dropped and the cables returned to normal analog signals, although an off-shoot using optical cable was carried out in Elie
Elie, Manitoba
Elie is the largest community in the Rural Municipality of Cartier in the Canadian province of Manitoba. The town of approximately 550 people is located approximately west of Winnipeg along the Trans-Canada Highway. The Assiniboine River forms the northern boundary of the municipality of...
, rotating the terminals though many households in the area.
Ida was followed by a flood of Canadian companies starting similar projects. In early 1980, TVOntario
TVOntario
TVOntario, often referred to only as TVO , is a publicly funded, educational English-language television station and media organization in the Canadian province of Ontario. It is operated by the Ontario Educational Communications Authority, a Crown corporation owned by the Government of Ontario...
, the educational television channel run by the Ontario government, set up 45 terminals in the Toronto area. In April 1981, New Brunswick Telephone
NBTel
NBTel was founded as the New Brunswick Telephone Company in 1888 after Bell Telephone Company of Canada's attempt to establish telephone service in the Maritime provinces failed. The company purchased the assets in New Brunswick, Canada from Bell Canada in 1889...
set up a system practically identical to Project Ida with a full suite of services, with somewhere between 20 and 100 terminals. The same month, Alberta Government Telephones
Alberta Government Telephones
Alberta Government Telephones was formed by the Liberal government of Alexander Cameron Rutherford in 1906 following the acquisitions by the government of several independent telephone companies...
started "Project VIDON", a smaller modem-based test in the Calgary
Calgary
Calgary is a city in the Province of Alberta, Canada. It is located in the south of the province, in an area of foothills and prairie, approximately east of the front ranges of the Canadian Rockies...
area. A month later, Bell Canada
Bell Canada
Bell Canada is a major Canadian telecommunications company. Including its subsidiaries such as Bell Aliant, Northwestel, Télébec, and NorthernTel, it is the incumbent local exchange carrier for telephone and DSL Internet services in most of Canada east of Manitoba and in the northern territories,...
announced their "Vista" project in Toronto and Montreal, in partnership with the Toronto Star
Toronto Star
The Toronto Star is Canada's highest-circulation newspaper, based in Toronto, Ontario, Canada. Its print edition is distributed almost entirely within the province of Ontario...
and the Southam Press
Canwest News Service
Postmedia News is a national news agency with correspondents in Canada, Europe, and the United States and is part of the Canadian newspaper chain owned by Postmedia Network Inc.-History:...
who would provide content. This test eventually expanded to between 500 and 1000 terminals.
Telidon generated interest outside Canada as well. A major foreign sale was made in July 1980 to the government of Venezuela, who set up a test system to provide information on health, social and economic aid programs to the vast numbers of people moving into Caracas
Caracas
Caracas , officially Santiago de León de Caracas, is the capital and largest city of Venezuela; natives or residents are known as Caraquenians in English . It is located in the northern part of the country, following the contours of the narrow Caracas Valley on the Venezuelan coastal mountain range...
from rural areas.
A number of U.S. companies also expressed an interest, and started plans to roll out their own Telidon-based teletext systems. As early as 1978, AT&T
AT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
and CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...
had been experimenting with the idea of a videotex service, and were drawn towards the Telidon efforts. In 1982 they rolled out an experimental system known as "Venture One" in Ridgewood, New Jersey
Ridgewood, New Jersey
Ridgewood is a village in Bergen County, New Jersey, United States. As of the 2010 United States Census, the village population was 24,958. Ridgewood is an affluent suburban bedroom community of New York City, located approximately northwest of Midtown Manhattan.The Village of Ridgewood was...
, equipping some homes with stand-alone terminals from AT&T, and others with set-top boxes. The test ran for seven months from 1982 to 83, and was considered a success, so much so that AT&T publicly announced plans to introduce a commercial system in 1984.
Telidon becomes NAPLPS
AT&TAT&T
AT&T Inc. is an American multinational telecommunications corporation headquartered in Whitacre Tower, Dallas, Texas, United States. It is the largest provider of mobile telephony and fixed telephony in the United States, and is also a provider of broadband and subscription television services...
was so impressed with the Telidon that they started a standardization effort with Bell and the DoC. AT&T contributed two major additions to the system; the ability to define your own character sets, and the ability to wrap up multiple graphics commands into a "macro". The former provided for the creation of small graphics that could be sent with a low transmission cost, which is useful in certain roles where the graphics can be arranged in a grid, like a chessboard. The later allowed the programmers to create a commonly used graphical element, the AT&T logo for instance, and save it to a macro. The graphic can then be re-created with a single instruction in any page that needed it.
The resulting system emerged in 1983 as NAPLPS
NAPLPS
NAPLPS is a graphics language for use originally with videotex and teletext services. NAPLPS was developed from the Telidon system developed in Canada, with a small number of additions from AT&T...
, while the transmission method that encoded information into the vertical blank interrupt
Vertical blank interrupt
A vertical blank interrupt is a programming technique used in some systems, notably video games and consoles, to allow program code to be run in the periods when the display hardware is turned off, waiting for the TV to complete its vertical blank.Since the vertical blank period occurs at the...
of a TV signal became the NABTS
NABTS
NABTS, the North American Broadcast Teletext Specification, is a protocol used for encoding NAPLPS-encoded teletext pages, as well as other types of digital data, within the vertical blanking interval of an analog video signal...
standard. Major articles in Byte Magazine introduced the NAPLPS system to a wider audience, spread over a four month period in the February, March, April, and May 1983 issues.With the standard complete, the U.S. teletext plans started moving forward. NAPLPS' ability to draw complex graphics was particularly interesting to U.S. vendors, as it allowed them to draw network or advertiser logos.
By this point the technical development of Telidon was complete, and that portion of the Canadian government's involvement wound down in the summer of 1983. Further efforts were aimed at helping develop a commercial marketplace for Telidon systems and content, running for another year.
Commercial efforts
One of the longest-lived Telidon deployments was "Project Grassroots", a follow-on to the services developed as part of the earlier Project Ida and run on its machines in Winnipeg. Unlike Ida, Grassroots ran on modemModem
A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...
s instead of cable links and was aimed specifically at farmers, providing a number of weather reports and other information, as well as optional links to live commodities pricing on various exchanges. Prices were high: in addition to purchasing a terminal there was an additional one-time $100 set-up fee, the annual fee was $150, and there was a $19.00/hr charge to connect to the service, and another $6.00/hr for "communications". Nevertheless, Grassroots grew into a system that distributed 20,000 pages of information to farmers created by Infomart. Based in Winnipeg
Winnipeg
Winnipeg is the capital and largest city of Manitoba, Canada, and is the primary municipality of the Winnipeg Capital Region, with more than half of Manitoba's population. It is located near the longitudinal centre of North America, at the confluence of the Red and Assiniboine Rivers .The name...
, Grassroots expanded to serve Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
, Saskatchewan
Saskatchewan
Saskatchewan is a prairie province in Canada, which has an area of . Saskatchewan is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, and on the south by the U.S. states of Montana and North Dakota....
, northern Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....
, and in 1985, the northern United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
.
A major effort to introduce Telidon in a public setting was the NABU Network
Nabu Network
The NABU Network was an early home computer system which was linked to a precursor of the Internet, operating over cable TV. It operated from 1982 to 1985, primarily in Ottawa, Canada...
. Unlike traditional Telidon systems, NABU terminals were complete home computer
Home computer
Home computers were a class of microcomputers entering the market in 1977, and becoming increasingly common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single nontechnical user...
s in their own right, using the Zilog Z80
Zilog Z80
The Zilog Z80 is an 8-bit microprocessor designed by Zilog and sold from July 1976 onwards. It was widely used both in desktop and embedded computer designs as well as for military purposes...
CPU and running a CP/M
CP/M
CP/M was a mass-market operating system created for Intel 8080/85 based microcomputers by Gary Kildall of Digital Research, Inc...
clone, but booting and launching programs over the cable modem
Cable modem
A cable modem is a type of network bridge and modem that provides bi-directional data communication via radio frequency channels on a HFC and RFoG infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high...
. It launched with about 100 programs, mostly games, but also including personal finance packages and such, as well as using Telidon for online banking and other consumer services. Users bought the hardware for $950 and connected it to their color television, accessing programs via cable for $8 to $10 per month. After the official launch on Ottawa Cablevision in October of 1983, the NABU Network was introduced by Ottawa's Skyline Cablevision in 1984 and a year later in Sowa, Japan, via a collaboration between NABU and ASCII Corp
ASCII (company)
was a publishing company based in Tokyo, Japan. It became a subsidiary of Kadokawa Group Holdings in 2004, and merged with another Kadokawa subsidiary MediaWorks on April 1, 2008, and became ASCII Media Works. The company published Monthly ASCII as the main publication...
. NABU machines used Telidon for online banking and other services.
A significant showcase for the Telidon system was set up for the Third General Assembly of the Inuit Circumpolar Council, hosted in Frobisher Bay
Frobisher Bay
Frobisher Bay is a relatively large inlet of the Labrador Sea in the Qikiqtaaluk Region of Nunavut, Canada. It is located in the southeastern corner of Baffin Island...
on Baffin Island
Baffin Island
Baffin Island in the Canadian territory of Nunavut is the largest island in the Canadian Arctic Archipelago, the largest island in Canada and the fifth largest island in the world. Its area is and its population is about 11,000...
in July 1983. A database of information about the conference and its services was hosted by Teleglobe Canada in Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
on their Novatex system, with the information translated into English, French, Danish, Inuktitut, Greenlandic, Labradorian, Inupiag, Yupik and Western Arctic. Sixteen Telidon terminals, supplied by Microtel, were located at various sites in Frobisher Bay, with additional terminals in Vancouver
Vancouver
Vancouver is a coastal seaport city on the mainland of British Columbia, Canada. It is the hub of Greater Vancouver, which, with over 2.3 million residents, is the third most populous metropolitan area in the country,...
, Washington D.C., Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...
, Anchorage, Bethel
Bethel
Bethel was a border city described in the Hebrew Bible as being located between Benjamin and Ephraim...
, Barrow
Barrow, Alaska
Barrow is the largest city of the North Slope Borough in the U.S. state of Alaska. It is one of the northernmost cities in the world and is the northernmost city in the United States of America, with nearby Point Barrow being the nation's northernmost point. Barrow's population was 4,212 at the...
, Nuuk
Nuuk
Nuuk, is the capital of Greenland, the northernmost capital in North America and the largest city in Greenland. Located in the Nuup Kangerlua fjord, the city lies on the eastern shore of the Labrador Sea and on the west coast of Sermersooq. Nuuk is the largest cultural and economic center in...
, as well as other northern communities. Communications were provided by Bell Canada
Bell Canada
Bell Canada is a major Canadian telecommunications company. Including its subsidiaries such as Bell Aliant, Northwestel, Télébec, and NorthernTel, it is the incumbent local exchange carrier for telephone and DSL Internet services in most of Canada east of Manitoba and in the northern territories,...
, Teleglobe
VSNL International Canada
VSNL International Canada is an international telco carrier. The company is a subsidiary of Tata Communications, part of India's Tata Group. Part of their recent work has involved the updating of the CANTAT transatlantic cable system that connects the United Kingdom and Newfoundland under the...
, Greenland Telecommunications and the Danish Post and Telegraph
Post Danmark
Post Danmark A/S is the company responsible for the Danish postal service. Established in 1995 following political liberalization efforts, it has taken over the mail delivery duties of the governmental department Postvæsenet ; it was turned into a public limited company in 2002...
.
The Canadian government also invested in Telidon as a way of distributing graphical information. Transport Canada
Transport Canada
Transport Canada is the department within the government of Canada which is responsible for developing regulations, policies and services of transportation in Canada. It is part of the Transportation, Infrastructure and Communities portfolio...
ran a system called "TABS" that installed terminals in many airports, where pilots could quickly look up weather information and NOTAM
NOTAM
NOTAM or NoTAM is the quasi-acronym for a "Notice To Airmen". NOTAMs are created and transmitted by government agencies and airport operators under guidelines specified by Annex 15: Aeronautical Information Services of the Convention on International Civil Aviation...
s. Statistics Canada
Statistics Canada
Statistics Canada is the Canadian federal government agency commissioned with producing statistics to help better understand Canada, its population, resources, economy, society, and culture. Its headquarters is in Ottawa....
also used Telidon as a way to distribute graphs and other information in their CANSIM system using their TELICHART software that converted tables of data into NAPLPS commands. Environment Canada
Environment Canada
Environment Canada , legally incorporated as the Department of the Environment under the Department of the Environment Act Environment Canada (EC) (French: Environnement Canada), legally incorporated as the Department of the Environment under the Department of the Environment Act Environment...
used Telidon terminals to produce video feeds that could then be broadcast on local cable feeds.
In the Toronto area, "Teleguide" terminals were common fixtures at larger shopping malls, government buildings (e.g. Scarborough Civic Centre
Scarborough Civic Centre
The Scarborough Civic Centre, located in Toronto, Ontario, was designed by architect Raymond Moriyama for the then Borough of Scarborough. It was officially opened by then mayor Albert Campbell and Queen Elizabeth II in 1973...
) and notably the Toronto Eaton Centre
Toronto Eaton Centre
The Toronto Eaton Centre is a large shopping mall and office complex in downtown Toronto, Ontario, Canada, named after the now-defunct Eaton's department store chain that once anchored it. In terms of the number of visitors, the shopping mall is Toronto's top tourist attraction, with around one...
. Run by London, Ontario
London, Ontario
London is a city in Southwestern Ontario, Canada, situated along the Quebec City – Windsor Corridor. The city has a population of 352,395, and the metropolitan area has a population of 457,720, according to the 2006 Canadian census; the metro population in 2009 was estimated at 489,274. The city...
's Cableshare, the system relied on an 8085-based microcomputer which drove several NAPLPS terminals fitted with touch screens, all communicating via Datapac
DATAPAC
DATAPAC was Canada's packet switched X.25-equivalent data network. Operated first by Trans-Canada Telephone System, then Telecom Canada, then the Stentor Alliance, it finally reverted to Bell Canada when the Stentor Alliance was dissolved.-Use:...
to a back-end database. The system offered news, weather and sports information along with shopping mall guides and coupons. Rollouts were announced in several other cites as well.
The largest efforts were made in the United States. After the Venture One experiments in 1982/3, AT&T decided not to pursue a videotex service of its own, but instead provide service and support to other companies who wanted to. CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...
invested considerable capital in the development of their ExtraVision
ExtraVision
ExtraVision was a short-lived teletext service created and operated by the American television network CBS in the early-to-mid 1980s. It was carried in the VBI of the video from local affiliate stations of the CBS network...
service, which also included closed captioning
Closed captioning
Closed captioning is the process of displaying text on a television, video screen or other visual display to provide additional or interpretive information to individuals who wish to access it...
and channel information along with more traditional Telidon information. Affiliate stations could also insert their own content into the streams, although the high cost of the systems needed to do this made it relatively rare.
AT&T also partnered with Knight-Ridder Newspapers to form Viewdata, a holding company that operated the "Viewtron
Viewtron
Viewtron was an early online service offered by Knight-Ridder and AT&T. It started as a videotex service requiring users to have a special terminal, the AT&T Sceptre, then became a computer-based service as Commodore and other personal computers became important in the marketplace...
" service. Test marketed in Florida in 1980, the service expanded to the entire southern Florida area by 1983, and then expanded to much of the eastern seaboard. Viewdata started primarily as a news service, but over time included more and more features. As it operated over modems in a pure videotex format, it was able to offer a variety of two-way services including e-mail and bulletin boards. A similar system was "Gateway", run by AT&T and the Los Angeles Times
Los Angeles Times
The Los Angeles Times is a daily newspaper published in Los Angeles, California, since 1881. It was the second-largest metropolitan newspaper in circulation in the United States in 2008 and the fourth most widely distributed newspaper in the country....
.
In 1984 Tribune Media Services
Tribune Media Services
Tribune Media Services is a syndication company owned by the Tribune Company.The company has two divisions, "News and Features" and "Entertainment Products"...
(TMS) and the Associated Press
Associated Press
The Associated Press is an American news agency. The AP is a cooperative owned by its contributing newspapers, radio and television stations in the United States, which both contribute stories to the AP and use material written by its staff journalists...
operated a cable television channel called "AP News Plus" that provided NAPLPS-based news screens to cable television subscribers in many U.S. cities. The news pages were created and edited by TMS staffers working on an Atex editing system in Orlando, Florida, and sent by satellite to NAPLPS decoder devices located at the local cable television companies. The images were rendered locally, and then sent out as normal television signals to the customers. This avoided the need to send entire channels of video over satellite to the affiliate stations, instead, a small amount of data was sent and allowed the video to be re-created, for significantly less cost.
Problems
Test deployments demonstrated the problems that most other teletext systems also discovered: without an enormous amount of content, viewer interest is difficult to maintain. While large Telidon deployments might hold tens of thousands of pages, users were able to quickly exhaust the content in their particular areas of interest, suggesting that systems would have to contain hundreds of thousands of pages in order to remain interesting for longer periods. As Gordon Thompson of Bell Northern Research put it, "all of the excitement is in the expectation; the reality is really quite disappointing."Most teletext systems, Telidon included, were created in the context of the broadcast model, where the content would be provided by large vendors and then pushed one-way to the user in a fashion similar to television or newspapers. Interactivity was generally limited to menu selections or providing information on forms (like online banking
Online banking
Online banking allows customers to conduct financial transactions on a secure website operated by their retail or virtual bank, credit union or building society.-Features:...
). This placed the entire burden of creating the content on the service providers and their partners, an expensive and time-consuming process. Since much of the content in question was already available on different media controlled by the same companies, teletext services also had the problem of competing with encumbent mediums that were less expensive and better developed.
Telidon was also expensive. When it was introduced the DoC expected terminals to be available for $200 to $300 by 1982, but this did not come to be. The largest suppliers of terminals were Electrohome
Electrohome
Electrohome was one of Canada's largest manufacturers of television sets from 1949 to 1984. The company was also involved in television broadcasting....
, Norpak and Microtel, whose terminals ranged between $1,800 and $2,500. During the development period the hardware manufacturers felt that demand would drive down prices to less than $600, however, results from trials indicated that even this would be considered too expensive for the mass market.
Telidon disappears
By the mid-1980s, home computerHome computer
Home computers were a class of microcomputers entering the market in 1977, and becoming increasingly common during the 1980s. They were marketed to consumers as affordable and accessible computers that, for the first time, were intended for the use of a single nontechnical user...
s with graphics capabilities similar to Telidon had already come and gone, driving prices to points far below even the simplest Telidon terminal. A second generation of machines like the Apple Macintosh, Commodore Amiga and Atari ST
Atari ST
The Atari ST is a home/personal computer that was released by Atari Corporation in 1985 and commercially available from that summer into the early 1990s. The "ST" officially stands for "Sixteen/Thirty-two", which referred to the Motorola 68000's 16-bit external bus and 32-bit internals...
were entering the market with capabilities Telidon systems could not match. At the same time, information services like CompuServe
CompuServe
CompuServe was the first major commercial online service in the United States. It dominated the field during the 1980s and remained a major player through the mid-1990s, when it was sidelined by the rise of services such as AOL with monthly subscriptions rather than hourly rates...
and The Source were offering a usable online experience that Telidon failed to offer.
For all of these reasons, interest in Telidon, and Videotex in general, quickly faded. The government's funding of the Telidon efforts came to an official end on 31 March 1985, at which point $69 million had been spent. It was estimated that another $200 million had been invested by various industry partners, $100 million of that by Bell Canada. Most of the early test systems had ended their runs by 1982, while the commercial systems persevered for a few years longer; NBC
NBC
The National Broadcasting Company is an American commercial broadcasting television network and former radio network headquartered in the GE Building in New York City's Rockefeller Center with additional major offices near Los Angeles and in Chicago...
's system ended in January 1985, followed by NABU in 1985/6, and then ExtraVision, Viewtron and Gateway in March 1986. In spite of these services finding some level of consumer demand, none were able to find a pricing structure that paid for their operation while still being interesting to their consumer base.
Telidon systems continued to be used as a one-way medium for some time. A common use was to use Telidon terminals to produce video that was then broadcast for viewing, rather than the digital information itself. Systems like this were common for informational displays in airports and other public areas, as well as information displays for cable TV stations.
Legacy
The failure of the Telidon efforts was a topic of considerable discussion in Canada, part of a similar and wider conversation on the entire concept of videotex that took place in the late 1980s and early 1990s. Many of the Telidon criticisms focused on the role of government in the development of the systems, pushing a technology that no one really wanted.After Telidon was declared dead and most of the commercial efforts had ended, NAPLPS received a fresh breath of life as the basis of the Prodigy online service. In the time between efforts like Viewtron and the launch of Prodigy in 1988, personal computer
Personal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
s with the ability to view NAPLPS graphics with ease had become common, and modem speeds had increased to the point where the data was no longer overwhelming. After a promising start, Prodigy management invoked a series of blunders that seriously upset their customer base, and the arrival of the World Wide Web
World Wide Web
The World Wide Web is a system of interlinked hypertext documents accessed via the Internet...
in the mid-1990s killed it off.
NABTS, the communications protocol for embedding data in the TV signal, also saw continued use after the Telidon project ended. It was widely used for closed captioning
Closed captioning
Closed captioning is the process of displaying text on a television, video screen or other visual display to provide additional or interpretive information to individuals who wish to access it...
support, although not the only system available. It was also used for Microsoft
Microsoft
Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
's WebTV for Windows and Intel's Intercast
Intercast
Intercast was a short-lived technology developed in 1996 by Intel for broadcasting information such as web pages and computer software, along with a single television channel. It required a compatible TV tuner card installed in a personal computer and a decoding program called Intel Intercast Viewer...
. Both used custom tuners, in the form of plug-in cards for PC's, that captured the information encoded into the VBI or even an entire TV channel.
For his work on Telidon, Herb Bown received the Order of Canada
Order of Canada
The Order of Canada is a Canadian national order, admission into which is, within the system of orders, decorations, and medals of Canada, the second highest honour for merit...
and the gold medal for engineering excellence from the Association of Professional Engineers of Ontario. The Touche Ross New Perspectives Award was awarded to Herb Bown and Doug O'Brien. Bown later formed IDON Corp to develop interactive teaching materials.
Further reading
- Bown, H.G., O'Brien, C.D., Sawchuck, W., and Storey J.R. "A General Description of Telidon: A Canadian Proposal for Videotex Systems", CRC Technical Note No. 697-E, Department of Communications, December 1978
- Dave Godfrey and Ernest Chang, "The Telidon Book: Designing and Using Videotex Systems", Reston Publishing, 1981, ISBN 0835975487
- Paul Hurly, Matthias Laucht and Denis Hlynka, "The videotext/teletext handbook: Home and office communications using microcomputers and terminals", Harper & Row, 1985, ISBN 0060429925
- Terrence Devon, "Interactivity and the Popular Support for Telidon", Canadian Journal of Communication, Volume 16 Number 2 (1991)
External links
- Mining in Manitoba, originally a Telidon system, this site was later converted to HTML format by the R. D. Parker Collegiate
- "Graphic Variations on Telidon", a 16 mm film about Telidon by Pierre Moretti for the National Film Board
- Inventing the Internet Age, a CBC Digital Archive video showing Telidon in use.