**A blast from the past: the Schweizer Fernsehen test card introduced from 1972 onwards was created by a test card generator. Photograph from 1978.** Museum of Communication

Television test card – distant memory of the nightly broadcast shutdown

Once upon a time, television stations didn’t broadcast round the clock. Late at night and in the morning, there was a break in transmission. The symbol for these time-outs was the PTT television test card. A look back at a not too distant echo of a time when life wasn’t moving quite so fast – the test card hasn’t been gone all that long.

Juri Jaquemet

Dr. phil., Curator of the Information and Communication Technology Collection, Museum of Communication, Berne

Test cards are a relic of the age of terrestrial television reception. The signals broadcast by the transmission tower were beamed into the home via an antenna. The main purpose of the test card was to calibrate and align the receiving equipment. Through analysis of the patterns on the screen, the quality of reception could be ascertained and malfunctions or defects identified. Specially trained radio and television engineers were responsible for this task, and a glance at the vocabulary in use at the time suggests why expert personnel were needed: ‘image geometry’, ‘frequency response characteristic’, ‘interlace status’, ‘impulse and amplitude characteristics’ leave us scratching our heads in bewilderment. If the antenna was on the roof, adjusting it was sometimes a physical challenge that was not for the faint-hearted. It was a matter of rushing back and forth between the antenna and the test image on the box. Between the 1960s and 1980s, radio and television technicians didn’t have to do late-night special call-outs to adjust television sets after shutdown. TV programmes were mainly broadcast in the late afternoon and evening. If no Swiss Broadcasting Corporation (SRG) programme was on the air, the Post-, Telefon- und Telegrafenbetriebe (PTT) would temporarily broadcast the test card. The state-owned enterprise PTT not only took care of the country’s postal and telephone services, but also dealt with the technical aspects of television, such as transmission systems and studio equipment. In the TV towers the test card, which in the early days was held on a photographic slide, was converted to an electronic signal by a slide scanner and transmitted. Enthusiasts could tell from the test card where the signal was being broadcast from. A code letter or an abbreviation in a particular field indicated the origin of the signal.

The classic test cards of the SRG and PTT

The test card used in TV test operation from 1953 to 1958 has so far been modestly documented. The centre of the image was dominated by a Swiss cross. The words ‘SCHWEIZERISCHE TELEVISION’ and ‘TELEVISION SUISSE’ indicated the origin of the signal. The design of the test card was modelled on a universal test pattern that was used in Europe in the 1950s. This pattern originated in America. The ‘Indian-head test pattern’ produced by the US company Radio Corporation of America (RCA), which has been used since 1939, was clearly also the inspiration for the Swiss version.

**US model for many later versions – RCA’s ‘Indian-head test pattern’, from 1939 onwards.** Wikimedia

**First generation of the Swiss test card around 1954. Photograph of a TV screen.** Museum of Communication

With the transition to regular test operation in 1958, a new test card was introduced at Swiss Television. Its distinguishing features were a white double circle and a prominent PTT logo with the Swiss cross. So it was obvious where the signal was coming from even when receiving in neighbouring countries. The word ‘Television’ no longer appeared on this test card. For understandable reasons, those in charge considered the designation unnecessary and an ‘information technology pleonasm’, according to the magazine Technische Mitteilungen PTT in 1959.

The Schweizer Fernsehen (Swiss Television) test pattern introduced in 1958. In the field with the number 3, the place of origin (transmitting station, studio, outside broadcast vehicle) can be identified, encoded as a number or letter. Museum of Communication

When colour television was introduced in 1968, the test card was adapted to the new conditions. The lower third of the image now featured a set of characteristic colours which corresponded to the internationally standardised colour bar signal. A grey scale was still present, as most TVs were still receiving their picture in black and white at that time. In 1972, the PTT gradually introduced a new test card that was fully customised to the age of colour television. The basis was no longer a slide. Test card generators now provided an image that was generated entirely electronically. The image basis was a grid pattern and a central circle with colour and grey scales. In the centre of the circle there was a black bar with a stylised Swiss cross to identify the origin of the signal, followed by the letters ‘PTT’. The remaining symbols and abbreviations defined the precise origin of the signal. For example, ‘SRG’ stood for the television studio in Zurich and ‘GNSO’ meant that the test card was coming from the transmitter on Monte Generoso. The highly detailed code identifying the country of origin wasn’t simply a solemn greeting from the PTT executives to their viewers. Since the Federal Republic of Germany also used a very similar image – known there as the ‘Funkbetriebskommission-Testbild’ (FuBK) – it made sense to feature the codes in the centre of the card. A test card from Philips was likely the inspiration for both images. With the abbreviation ‘PM5544’, the card was developed in the late 1960s for the PAL colour television system.

**Philips PM5544 colour test card, developed in the late 1960s. This test pattern presumably served as the model for the Swiss test card.** Wikimedia

**Bosch test card generator for generating the electronic colour test card with broadcasting transmitter identification letters. Used on Monte Generoso from about 1975 to 1990.** Museum of Communication

In praise of nothing

Initially, an annoying audio signal at 1,000 hertz was transmitted along with the test card. Its purpose was to calibrate the TV speakers. As early as the 1970s, however, PTT and SRG switched to broadcasting a mix of royalty-free light music. The test card was thus promoted to become a kind of meditative oasis of nothing – broadcast close-down as a luxury. These days, those plagued by news tickers and social media may sometimes secretly yearn for a return of the age of the test card. Similar pleasures such as a good book, a conversation with no time constraints or a good night’s sleep weren’t disrupted by the stress of potentially missing out on something (#fomo).

Becoming a memory

The test card’s demise was a slow, gradual fade-out. From the late 1980s onwards, foreign TV stations were being beamed into Swiss living rooms at virtually any time of the day via cable and satellite TV. In the 1990s, major European broadcasters then started broadcasting programmes 24/7. On commercial television, clairvoyants, fortune tellers and excitable salespeople plugging bizarre total-body workout equipment, as well as hard facts, replaced the mundane test card. As the former SRF media documentalist Jürg Hut has investigated for this article, from 1997 to 2005 the test card still led a pathetic marginal existence at Swiss Television. SF2 was already broadcasting Teletext pages instead. Only SF1 remained loyal to the test card for a few hours each day from Sunday to Friday. On Saturdays, it too broadcast Teletext pages in place of the test card. At the end of March 2005, the time had come. Swiss Television launched full 24-hour programming, and the test card was relegated to history. In the French-speaking part of Switzerland and in Ticino, TV technicians recall that the test card finally disappeared around 2005 as well.

Programme end followed by test card on TSR in 1996. YouTube / Qwertz-73

More of: 20th / 21st century Technology

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