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By the early eighties, it was starting to be considered desirable for computers to have color monitors. Home computers often made do with a TV set and accepted the consequent low resolution, but professional computers like the IBM PC were starting to try for color plus enough resolution for 80-column text at the same time.

One reason color TVs didn't have that much resolution is that (for reasons at least partly rooted in the need for backward compatibility with black and white TV) they lumped the color signal in with the luma signal (composite video). What was really needed was separate signals for red, green and blue, and connectors were invented for this, first with just one bit each, then with an analog signal for each.

But SCART was invented in 1977, and the pinout on Wikipedia shows separate pins for red, green and blue, so it looks to be exactly what a color monitor needs. So why was it not used for such? Was it just some version of NIH, or was there a technical problem with it?

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    SCART was popular in Europe. Are you asking why it wasn't popular in the USA? Related: retrocomputing.stackexchange.com/questions/5809/… – snips-n-snails Jun 23 '18 at 7:19
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    People made SCART cables e.g. for the Apple II GS, so I think technical problems can be ruled out. – dirkt Jun 23 '18 at 8:21
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    It's worth noting that there were some computers that used SCART as their primary connection method; the SAM Coupe is the one I had experience with at the time, but I'm pretty sure there were others, too. – Jules Jun 23 '18 at 16:31
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    Note that RGB-SCART was a lot better than plain SCART. – Thorbjørn Ravn Andersen Jun 24 '18 at 22:50
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Caveat: 'Why Not' questions are like 'What If' and rarely have a definite answer. It's an (educated) speculation at best.


In case of interface and connectors, NIH (Not Invented Here) is a big issue. Beside the fact that adding more interfaces costs money, manufacturers usually love to have closed systems where they control - and most important sell all parts. Just think why there is no common remote even though a majority uses the same technology and protocol, they assign the codes in different schemes - often even within the same brand.

Or think the many attempts of computer manufacturers to come up with proprietary connectors for standard interfaces. The most prominent example might be Apple and the switch for RS422 and mini DIN connectors for the Mac's serial interfaces. Sure, there can be many arguments made as being more reliable and so on, but all of them don't really matter in a desktop environment. What counts is that customers will have an easy way of using prepared Apple peripherals or will have to spend more (converter/cable) to connect standard devices.

The SCART story is even proving this as being a reverse NIH that backfired. Developed by the French TV makers' association in the 1970s (yes, Europe had still many TV manufacturers back then :)) as a common standard for interchange, they saw a chance to use it as a protectionist measure and 'supported' the government to adopt it as requirement for TVs sold in France. The 'rationale' was that foreign (non-French that is) manufacturers would avoid the additional cost of making special French-only TV-sets and thus leave them their market - while they could even save money by leaving the connector unpopulated on export units. Weird logic, isn't it?

Except that idea already hadn't worked some years before, when France selected SECAM as the colour standard to be. European manufacturers just modularized their TVs, eliminating next to all additional cost - while gaining more flexibility at the same time - leading to ultimately larger market shares overall and in France.

So with SCART, TV manufacturers started to not only fit SCART connectors to sets designated for France, but to all of them - starting with their top line models. By the beginning of the 1980s, most new TV sets in (Western) Europe featured a SCART connector accepting always composite video but also more often than not RGB.

While many of the upcoming home computers where designed primarily for the US market with a composite output meant to be used with a modulator, a SCART cable became a common add-on in Europe, eliminating the noise due to modulation and demodulation. Even more so for machines offering Y/C (like the C64) or full RGB. And French (Thomson et.al) home computers of course featured SCART out of the box :)) In the mid 1980s, SCART was the de facto standard for a colour monitor. Atari sold their STs in many countries with a ST to SCART cable.

If it's that great, why not in the US? Well, US and European markets were quite separated back then. Beside different technical norms (60 vs. 50 Hz and NTSC vs. PAL vs. SECAM) US customers where not only used to different designs, but also quite different user interfaces (*1). So except for few upper end models there was no common design. Even European manufacturers exporting to the US (quite a few) did set up separate production lines for special US designed models. As a result, SCART wasn't the ubiquitous interface it was in Europe, and thus not really interesting to US computer manufacturers.

Again, if SCART is that good, why did it (mostly) vanish for computer use even in Europe? SCART is tied to TV signals, and while this is good to somewhere up to VGA/SuperVGA, by now it would have been replaced anyway. But the true story is again about closed systems. Professional computers where usually sold as a system. Locked in status was not really an issue, and connecting to a TV rarely a goal. So using a generic interface did not bring any advantage (and was not forced by law anyway) - in contrast overseas manufacturers (at that time mainly Taiwan) could offer lower cost by huge volumes when just offering the most common solution. In this case the VGA connector.

Long story short, an inverted NIH being superseded by huge volume 'it works; who cares'.


Speaking of benefits of legal standards - USB for phone charging tells exactly the same story. People may have already forgotten, but less than 10 years ago next to every phone, PDA and alike had their own proprietary connector for charging, their own wall wart and often another proprietary cable for data exchange. It was due to force of the European Commission that the micro-USB connector became standard for charging of phones. Even Apple has to join by offering an adaptor. Beside reducing the need to carry several chargers, they also became dirt cheap (*2) not to mention that next to any computer can be used for charging. As a side effect the whole mobile business, from phones to tablets to cameras uses micro-USB. what a relief.

By now the Commission's force has run out (such measures are usually timed) - it's time for manufacturers to make the world incompatible again :(


*1 - For example it was even in the '80s still common for a TV to have a dial for selecting channels. Something that already went out of style in Germany somewhere in the early 1960s. We wanted to have function keys to sort the channels the way we liked them, not how they are aired.

*2 - I still remember paying 30 Euro for a replacement charger in the early 2000s - now they are 5 Euro at most and can be bought everywhere.

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    This is an interesting and alternative view to the answer I haven't thought of ! – Aybe Jun 23 '18 at 8:16
  • Not invented here and the fact that SCART was actually a protectionistic invention might have been the main factors. The bulkiness of the connectors might have added quite a bit. – tofro Jun 23 '18 at 8:47
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    The bulkiness actually might be positive. A good, easy to grip, almost impossible to connect the wrong way around connector is a good feature. SCART and DVI are nice examples to this. (granted, not on phone is similr sized devices, but on desktops, laptops and TV a larger connector simply is an advantage. – Hennes Jun 23 '18 at 12:07
  • I think the use of dials versus buttons relates to the fact that US television stations identified themselves with frequency-mapped channels. All stations that transmit on US channel 2 use the same frequency as each other; likewise all stations that transmit on channel 3, all that transmit on 4, etc. ITV in the UK may be identified as "channel 3", but people in different parts of the UK would need to tune their television sets to different frequencies in order to receive it. – supercat Jun 23 '18 at 20:32
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    Let us continue this discussion in chat. – Raffzahn Jun 23 '18 at 22:20
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As you know it's a French invention, and over here at some point, all TV sets that were to be sold in France must had such socket.

The indirect consequence is that any TV connected device sold here went this road too (video game console, personal computer, etc) very early as the other choice was RF because ironically, CVBS sockets on TVs started being widespread here only around the mid 90s.

Of course CVBS was possible from SCART, but with few notable exceptions such as VCRs, pretty much all devices were outputting RGB (right, there are a few VCRs that output RGB but they're extremely rare). Now the fact that some of these devices tricked by simply converting CVBS signal to RGB such as in the NES is another topic :)

In regards to color monitors, if you look at the acronym that SCART is (from Syndicat des Constructeurs d'Appareils Radiorécepteurs et Téléviseurs, "Radio and Television Receiver Manufacturers' Association"), you can see that it specifically targeted TV sets, rather than monitors with a potentially higher scan rate than 15 Khz; read here that a significant rework of the norm would have been required for it to accommodate these, i.e. not the right tool for the job.

To sum it up, here in France, many personal computers (e.g. Oric-1 (1984), Canon X-07 (1983), Thomson TO7 (1982); the French word for SCART is also Péritélévision) used TV sets as monitors through SCART as early as the 80s. Whether they were truly outputting RGB or cheating like the NES is another story (seeing that the TV automatically switches to AV is simply not enough).

In the end SCART was pretty much an alien like SECAM was, and with little doubt, the best implementation was in the country where it originated from.

(making this answer as a community wiki, improvements are welcome)

  • Good points, thanks! But early personal computer monitors like the 5153 had the same 15 kHz scan rate as NTSC, and even for monitors with higher frequency, surely the SCART connectors and cable would still work fine? – rwallace Jun 23 '18 at 7:42
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    Not an expert in electronics here but I suppose that if the monitor does 15 Khz and supports the same (non-separated?) synchronization, I see no reason why it wouldn't work. But please, get an expert advice first to avoid the risk of hurting your monitor, if at all ! – Aybe Jun 23 '18 at 7:58
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    For one, SCART does scale beyond 15 kHz, but more important it wasn'T so much a French than a European thing. Sure, it was initiated (and forced) by France, but it soon became a rather great interface all over Europ (and in fact even Japan). Just the US was left out :)) – Raffzahn Jun 23 '18 at 8:08
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    US loved 'never twice the same colors' through RF in fact :) – Aybe Jun 23 '18 at 8:21
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    @rwallace Atari sold theri ST line in some places with a SARCT cable. ST mid Res is running at 15.75 kHz. We often used an ST at a large TV for gaming - especially nice since the TV also supported 60Hz. And SCART can do even more. At home I use a HDMI to RGB converter to view Blue Ray on an early HD-Plasma without HDMI. Analogue connection is via SCART and, while maybe stretching the specs a bit, the picture (HD 1920x1080) is still great. – Raffzahn Jun 23 '18 at 8:21
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As a counter-example, SCART connectors were used on some computer monitors. I own a Phillips CM8833, which accepts RGB or CVBS input through a SCART connector (or separate connectors). This particular monitor was bought for use with an Acorn Archimedes computer via SCART (TTL RGB), but it was also popular for Atari and Spectrum machines. There are pictures of a CM8833 (including the rear connectors) here.

As others have implied, SCART was a European standard, and the PC-compatible market was led by IBM in the USA. It is notable that these examples of SCART monitors are all non-IBM-compatible machines. Once everything became "PC" (or Mac) in the 1990s, SCART monitors were an irrelevance.

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