In the late 80s, a video revolution took place in our country. Films, music programs and even erotic films recorded on magnetic tape surged into the USSR. The accessibility of the most recently banned spectacles intoxicated, causing vague hopes that soon everything will become “like abroad” with us. But this social phenomenon had another side - the technical one.
Video, video ...
At first, all the video equipment was very expensive. No one was surprised at newspaper advertisements offering to change a summer cottage or even a room in a communal apartment for a coveted apparatus of the VHS system. And if the VCR itself was just an expensive thing, then the cost of a foreign TV just broke all conceivable records and was in direct contradiction with common sense. In the late eighties, a Japanese multisystem receiver could cost several thousand “wooden”, despite the fact that a salary of three hundred rubles was considered decent for a specialist.
How to connect video to domestic TVs
The happy owners of a Japanese or South Korean miracle soon came to the conclusion that our televisions could well be used to watch foreign video programs. Most Soviet devices, modern at that time, already had all the necessary devices for connecting video equipment, namely: the built-in PAL-SECAM decoder and the SCART connector on the back cover. They were also equipped with remote control or had the ability to easily install the necessary boards, control modules and infrared photodetectors. Immediately there was a shortage of appropriate connecting cables, which willingly filled up numerous cooperatives and private enterprises.
The simplest wiring
The wiring of the SCART connector itself is simple, especially since the first video lovers needed the simplest functions. Those who only wanted to watch the programs already recorded had three main contacts: the second and sixth (a jumper between them) was responsible for the sound, the twentieth for video, and, of course, an earthen (plate surrounding the entire connector) was needed. The same applies to those who bought the player - the device is relatively inexpensive compared to the “full video recorder”. It was necessary to use a shielded cable with a 75-ohm frequency impedance, but in practice, given the small length, many manufacturers neglected this condition, especially since the recording quality of most cassettes left much to be desired, and the connector's properties affected the clarity of the picture last.
In order to provide the ability to record to the device from an external low-frequency source (another VCR or TV) in the “audio mono” mode, the number of pins needed to be doubled by adding the 1st, 3rd (sound) and 19th (video) contacts.
These annoying 20 contacts and ground
As a rule, the connecting cord was a cable, on one side of which was a SCART connector, and on the other, two, four or six contact groups of the American RCA standard (called “tulips” for their specific shape). At its core, it was a simple adapter that allowed for galvanic connection of the source with a video monitor (TV). Video owners often swore, cursing the imperialists for their lack of desire for universal standardization, believing that 21 contacts for such a simple device is too much.
Only TV specialists for whom the SCART connector circuit did not constitute a “Chinese letter” could appreciate the full potential of this approach from the French Union of Electronics Manufacturers, in whose honor it received its name (Syndicat Des Constructeurs D'Appareils, Radiorecepteurs Et Televiseurs - SCART).
Why so hard? But why!
Unlike ordinary “tulips”, the SCART RCA connector has a number of advantages that provide wide control capabilities, better color reproduction and even unthinkable digital broadcasting in the early 80s (and it was developed in 1983).
Today, consumers who are little enlightened in electronics know that the variety of colors on the screen is created by only three components: red, green and blue. Separate their supply to the color module eliminates a number of interference and makes the picture more clear. This feature is provided by the SCART connector, in which the 7th, 11th and 15th contacts are designed to supply the RGB signal, and the alternating 5th, 9th and 13th contacts are used for shielding shells.
But this is not all the possibilities that the SCART connector has. The pinout suggests the possibility of automatically turning the TV on and off simultaneously with the source of the low-frequency signal (DVD or VCR), regardless of which company produced the equipment. The widescreen display mode also turns on automatically.
In addition to these functions, there are two digital contacts - the 12th and 14th, prophetically singled out by French engineers back in 1983, when almost all consumer electronics were analog. There is a connector for connecting a timer, it is under the tenth number.
So, 20 contacts and one general (21 in total) - this, it turns out, is not so much. For modern entertainment video centers, they are enough for now, although there’s not enough to turn on Dolby Surround ...