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Interconnects and Cables






Of all the different types of plugs and sockets used on AV equipment the most troublesome is the dreaded SCART connector. They’re cumbersome, expensive, the cables are always too long or too short, and they can be unreliable. There’s no escaping them though, SCART sockets have been fitted to pretty well all TVs and video recorders since the early 1980’s, and more recently, to laser disc players and satellite receivers as well.


For the record SCART is an acronym of Syndicat des Constructeurs d'Appareils Radio  Recepteurs et Televiseurs, but it was originally known as the Periteivision connector; Philips, bless ‘em tried to change the name to Euroconnector, but it seems we’re stuck with SCART. The standard is controlled by the European Committee for Electrotechnical Standardisation (otherwise known as CENELEC); the wiring protocols are set out in European and British specification documents EN 50 049 and BS 6552. There are several different conventions but the one’s you’re most like to come across are Types A, C, V and U. Lead Types A and V are partially wired and intended for audio-only and video-only interconnections respectively. The Type C or ‘9-pin’ SCART is the commonest configuration, this carries stereo audio and composite video signals. Type U, also known as ‘universal’ or ‘21-pin’ leads, have all their pins wired. In all cases the audio and video connections have to be ‘crossed’ so that inputs are wired to their respective outputs. Only SCART-to-SCART extension leads are wired ‘straight’ (i.e. pin 1 at one end is wired to pin 1 at the other end, and so on).  


Type C leads are suitable for most home cinema applications, connecting TVs, with video recorders and satellite receivers etc. A Type U lead is only necessary when using a Super VHS VCR or some Laser Disc players with a TV, that has an S-Video configured SCART socket, (instead of a specialised S-Video connector), or when both the TV and VCR are made by the same manufacturer and share a common remote control system. By the way, all Type U leads are S-Video ‘compatible’, so don’t be fooled into paying extra for this feature. Gold-plated connections are worth paying a little extra for, if you do a lot of plug-swapping, or your equipment is used in a damp or humid environment. Only buy branded leads from reputable audio and video dealers; avoid cheap and nasty cables sold in street markets or car boot sales, and you can’t go far wrong.


The SCART system works tolerably well connecting TV and video products together, that have multiple SCART sockets, but things start to get awkward when it comes to older TVs and VCRs with single SCART sockets, or video to audio interconnections. In the former case the solution is to use a SCART splitter box or cable. Two into one SCART leads enable two devices (a VCR and satellite tuner, for instance) to share one SCART socket on a TV, though this can lead to problems with signal interaction. SCART splitter boxes have switched inputs, the better ones are auto-sensing, and will connect whichever input is ‘live’ to the output.


Hardly any hi-fi components have SCART sockets, so if you want to connect the line-audio output from a VCR to an AV amp, for example, you’re going to need a SCART to phono cable, (unless the VCR has separate line audio output sockets, fortunately quite a few do!). This is where it can get a bit tricky, because you need to know which direction the signals will be travelling in. Simple SCART to phono leads have two, and sometimes three phono plugs (the third one is for composite video). Some have a little  switch on the SCART plug, so they can be used for input or output connections; others are one-way only (i.e. input or output), so make sure you get the right one. The alternative is a two-way SCART to phono lead, with six phono plugs (2 audio in, 2 audio out, and video in/out) on the other end. There’s a sort of unofficial colour code, to help distinguish between the various types of signals, black, red and white are most often used for audio, whilst yellow almost always means composite video, though don’t bank on it, and you’re on your own if you come across green or blue plugs...


RF, coaxial or Belling & Lee connector, otherwise known as aerial plugs and sockets rarely cause problems, though repeated plugging and unplugging can cause the sockets to become loose or fail. Satellite systems use a plug and socket called ‘F-connectors to link the dish to the receiver, again they’re pretty reliable. F-Connectors at the dish end of the cable sometimes suffer from contact problems, usually when they haven’t been properly weatherproofed. If your satellite TV picture is starting to look noisy it’s worth checking this first.


Occasionally you may come across older items of audio and video equipment fitted with round DIN connectors; they’re an absolute nightmare, with numerous wiring strategies, and anything from 2 to 9 pins. They also come in a number of different sizes, the commonest being the 4-pin mini DIN (aka Hosiden plug), used for S-Video signals on S-VHS and HI8 camcorders, VCRs, and some TVs. On standard DIN connectors there’s no easy way to work out what the various pins do; the only good news is that most audio and video dealers have cable-finder books stuffed full of every plug and socket combination known to man.



Ó R. Maybury 1995 0906






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