Until the mid-1980s, the test card was a common sight on RTÉ TV during daytime hours. Prior to that, RTÉ never really embraced the idea of a morning or early afternoon programme schedule (with the exception of weekends).
Ireland launched its own television service in December 1961. Initially, Telefís Éireann used a version of the British Test Card C. Unfortunately, no recordings or images exist of the TÉ version of the card.
A Telefís Éireann-branded version of Test Card E exists, but it’s unclear if this was used on air. As discussed in our history of the BBC trade test transmission, Test Card E was not popular with engineers in the UK, and consequently had a very short on-air life there.
In 1966, Ireland’s radio and TV services were merged, and Raidió Teilifís Éireann was born. A new test card design – produced by RTÉ engineer Paddy Clarke – was unveiled. It included separate frequency gratings for the 405-line and 625-line transmission systems.
In 1972, RTÉ switched to an electronically generated test pattern: the popular Philips PM5544. Although designed for 625-line transmission system, it was also radiated by RTÉ on their 405-line network. Though many other broadcasters were also guilty of this.
Although the PM5544 was broadcast during daytime hours, at closedown, the general rule of thumb was chroma bars. Around the mid-1980s, the chroma bars signal was modified, to have the bottom half of the bars in black and white.
These test signals would remain in use on both RTÉ TV channels until July 1996. From then, all non-programme time was filled by in-vision teletext.
At a future date, this article will be augmented with additional information, images and video.
In the meantime, we leave you with two test signals currently airing on spare capacity on the Irish Digital Terrestrial TV network: one is an updated, 16:9 version of the old PM5544 signal; the other is chroma bars and vision/audio sync test. Both signals are generated by the company that manages the Irish DTT transmission network – 2RN (a wholly owned subsidiary of Raidió Teilifís Éireann).
RELATED ARTICLE: early in-vision teletext in Ireland.
PICTURED: 2RN test card. COPYRIGHT: 2RN.