General Information

Serial #

1203

Part Number

1

Total Parts

2

AKA

N/A

Patents

N/A

General Description

FERROUS METAL CASING WITH SYNTHETIC TOP & SIDES/ SYNTHETIC CONTROLS & WORKING PARTS/ METAL WORKING PARTS/ GLASS? INDICATOR LIGHTS/ NON-FERROUS METAL FRONT PANEL

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

49.6 cm

Width

32.0 cm

Height

9.1 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Computing Technology

Category

Digital peripheral devices

Sub-Category

N/A

Manufacturer

AKA

Norpak

Country

Canada

State/Province

Ontario

City

Kanata

Context

Country

Canada

State/Province

Ontario

Period

1981-1985

Canada

This decoder is part of Canadian developed Telidon videotex technology created by the Communications Research Centre. The Telidon program began on August 15, 1978 and ended on March 31, 1985.

Function

This is a second-generation videotext decoder used to decode Telidon graphics images. The purpose of a decoder is to take the communications data that's transmitted over narrow bandwidth line, which would be the telephone line in this case, and convert it to something that can be put on to a display screen.

Technical

This decoder used a microprocessor and a 1200 baud modem to decode and convert communications data code to something that was displayable on a television display screen. This decoder used a bit plane that is a dot by dot image structure. While the graphic was not high quality, it was quite reasonable and the code was designed to be capable of expanding to handle higher resolutions. The system was designed to be forward and backward compatible, meaning it had the capability of displaying existing and future images, taking advantage of lowering memory costs to improve Telidon technology over time. In 1983, the North American Presentation Level Protocol Syntax (NAPLPS) graphics language develop from the Canadian Telidon system was formalized, ratified and adopted as a world standard for graphics transmission by computer. The Norpak Mark 2 decoder was the first attempt at making a lower cost device. It worked, but there were problems trying to commercialize the technology. The first Mark 2s failed as they did not have very good power supplies. However, the Mark 2 would go one to be used for many of Telidon field trials.

Area Notes

Unknown

Details

Markings

DECAL ON UNDERSIDE READING 'norpak CANADA/ Model MK2/ Serial 1203'/ WHITE LETTERING ON FRONT READING 'norpak/ COMPUTER DISPLAY SYSTEMS/ Made in Canada'/ WHITE PRINTED CONTROL FUNCTIONS ON FRONT & BACK/ GREY DECAL ON FRONT READING 'ASSET NUMBER/ 18390/ CRC SHIRLEY BAY'

Missing

N/A

Finish

CASING PAINTED BLACK ENAMEL/ WOOD GRAIN SYNTHETIC TOP & SIDES/ BLACK & WHITE SYNTHETIC PARTS/ PLATED PARTS

Decoration

N/A