Tell me about the difference between SCART and Component Video

This is the most common question that we are asked when people telephone us for advice.

To understand the answer it is first useful to run through some facts about video signals and how pictures are sent down cables.

SCART output

A SCART socket has the potential to send video signals in three different ways:

• Composite video (poor quality)
• S-Video (better)
• RGB (best)

The RGB output is the one you would want to use and it is commonly referred to as component video. However, there are different types of component video and this one is simply three signals, a red signal, a green signal and a blue signal. Most importantly it does not include a synchronisation signal which you will learn later is the cause of a problem.

Component video input

The component video input on your TV/Plasma can be one of five different types:

• 5 RCA/phono or BNC sockets which are marked R, G, B, HS, VS.

  This is a Component RGB input, but unlike your SCART it requires two additional signals, HS - Horizontal Synchronisation and VS - Vertical Synchronisation. To connect to this you need to buy a convertor box which creates these additional synchronisation signals. These cost £75 - £100 plus cables and we do not currently sell them though we will very shortly.

• 5 RCA/phono or BNC sockets which are marked R/Y, G/Pb, B/Pr, HS, VS

  This accepts the RGB component video described above but also accepts a component YUV using just the first three sockets. Component YUV is the highest quality video signal and magazines correctly recommend you use it. But it is not compatible with a SCART output and is only easily used with a DVD that also has a component YUV output. If you want to use this input for your SCART based DVD or Digibox then you will need to buy a SCART to YUV convertor, you can buy one of these by clicking here.

• 3 RCA/Phono sockets marked R, G, B

  This is uncommon but you are lucky if you have it. In our experience this is more common on projectors than TVs. You can buy a QED AV19 cable which is SCART to 6 RCA/phonos. The 6 signals are Red, Green , Blue, Composite Sync. Left audio and Right audio. You will want to use the R, G and B and possibly the audio if you have an audio input that you also want to use. You can buy the AV19 by clicking here.