tinelix / tdatext

TDAText teletext-styled font family based on Philips SAA52XX/SAA55XX/TDA93XX IC character set

TDAText

TDAText teletext-styled font family based on Philips SAA52XX/SAA55XX/TDA93XX IC character set and adapted for use in computer typography systems.

The font contains punctuation, Latin, German, Spanish, Czech, French, Italian, Swedish, Estonian and Cyrillic letters, including Russian, Belarusian and Ukrainian, as well as more than 100 glyphs for emoji.

Prehistory

An initial version of the original font was demonstrated by Floris V. van Nes in August 1986, called IPO-Normal. This font made it possible to improve the legibility of messages transmitted through TV information services such as teletext, since the resolution of the TV signal was limited to save bandwidth on television channels.

In November of the same year, Philips Semiconductors (later NXP) introduced one of the first video processors with teletext support, the SAA5231. And 4.5 years later, it introduced the SAA5243 teletext decoder, which used external modifications of the IPO-Normal font. Later, separate versions of video processors were released without teletext decoding, but with teletext-style character generation, such as the SAA5541.

The following symbols have been changed: $ (dollar sign), % (percent sign), & (ampersand), @ (at), x and y letters.

The software behind these Philips TV chips was especially popular in the late 90s and early to mid-2000s. For example, Philips, Samsung, LG, Sony and other electronics manufacturers often used these chips in CRT televisions built on a chassis:

• Philips: L01
• Samsung: KS1A/B, KS2A, KS9A/B, S16A/C and etc.
• LG: MC-019A, MC-049B
• Sony: BE-4, BE-5, FE-1, FE-2

The current version of the font, called TDAText, also contains various improvements to accurately represent characters, including additional Unicode characters not originally included, and adaptation for computer typography systems, since square pixels were not used to display text or OSD information on the CRT TVs - pixel aspect ratio was 1:2 instead of 1:1.

Known Limitations

Due to the positioning of this font as a reworked version of IPO-Normal font, you may encounter some limitations when designing characters:

• Character matrix size: 12x10 (Regular), 12x15 (Condensed)
• Limited glyphs for emoji
• No available glyphs for Polish, Rumanian languages
• A comfortable size for displaying characters on the screen is 15pt or (n*15)pt at 96 dpi.

License

SIL Open Font License 1.1. See LICENSE.TXT file.