Connectors - the different types

For our purposes, there are three types of signal that we need to consider:
Data - from PCs, Macs, etc.
Video - from camcorders, satellite boxes, cable TV boxes, DVD players, video recorders, security cameras, TV aerials, etc.
Audio - from computer sound cards, the above video sources, etc.

Often the same connector is called by different names.

	15-pin D-sub. An analogue connection, it is the most common connection to computer monitors. Also known as VGA.
	BNC. This refers to the physical form of the connector. Various suggestions are put forward as to what it stands for, including British Naval Connection. However, it is a sturdy way to connect and involves a push and twist. Adaptors from phono to BNC are available.
	Co-axial. Commonly refers to the type of RF (radio frequency) video connection you get with terrestrial antennae. A simple pin enclosed by a ring form, it sends video and audio down the same line.
	Component. The best analogue connection for video. It sends the signal in three separate components and is found on high-end equipment like DVD players. Physically, the connectors can be phono or BNC types.
	Composite. A video-only signal sent down one cable. Commonly coded with a yellow plug this is often used with video recorders and camcorders. A simple method and not as good as S-video or component because the colour signals are not separate but composited. Physically, the connector can be a phono or BNC type.
	DFP. Digital Flat Panel connection was used in earlier digital LCD computer monitors. It was restricted by resolution and has been superseded by DVI. DVI-I graphics cards can be connected to DFP monitors by an adaptor. The image shows a DFP socket.
	DisplayPort. VESA's rival to UDI. According to VESA, this will carry high bandwidth digital video with content protection to compters and video equipment. Audio can also be carried. Still in development, this will fight with UDI for dominance - only one is likely to survive.
	DVI-D. Digital Visual Interface (Digital only) is used in LCD computer monitors. A competitor to DFP, it allows higher resolutions and will connect to digital DVI and DFP graphics cards (with an adaptor). It is being superseded by DVI-I. Single Link DVI supports a maximum bandwidth of 165 MHz (1920 x 1080 at 60 Hz, 1280 x 1024 at 85Hz). A single link implementation utilizes 12 of the 24 available pins. Dual Link DVI supports 2 x 165 MHz (2048 x 1536 at 60 Hz, 1920 x 1080 at 85 Hz). A dual link implementation utilizes all 24 of the available pins. The maximum recommended length for these cables is just 7.5m - we can supply special fibre optic cables that can send signals to 100m.
	DVI-I. Digital Visual Interface (Integrated) is the most versatile of connectors for monitors. A DVI-I connection on a monitor will connect to DVI-I graphics cards and to DVI-D, DFP and 15-pin VGA analogue cards with suitable adaptors. Conversely, you can connect DVI-D and DFP monitors to DVI-I cards with suitable adaptors. Single Link DVI supports a maximum bandwidth of 165 MHz (1920 x 1080 at 60 Hz, 1280 x 1024 at 85Hz). A single link implementation utilizes 12 of the 24 available pins. Dual Link DVI supports 2 x 165 MHz (2048 x 1536 at 60 Hz, 1920 x 1080 at 85 Hz). A dual link implementation utilizes all 24 of the available pins. The maximum recommended length for these cables is just 7.5m - we can supply special fibre optic cables that can send signals to 100m.
	Euro Connector - see 'SCART'.
	HDMI. High Definition Multimedia Interface was released in 2002 and is set to become the standard for high end image and sound transmission. It will carry data or video signals as well as audio. It is supported by the industry giants and has everything going for it. It carries an all-digital, uncompressed video signal up to the highest HD (high definition) standard and beyond. It will also carry up to eight channels of digital audio. Talk between devices is possible and so well designed components in a system should be able to communicate with each other and configure and adjust intelligently. It is backwards compatible with DVI sources and displays. So you can connect, for example, a PC with a DVI card to a plasma display with HDMI-in. Conversely, you can connect a DVD player with HDMI out to a plasma display with DVI-in. Download this overview for more information. UDI should be compatible with HDMI.
	Mini-jack. A mono or stereo audio connection. 3.5 mm in diameter, this is often used in low-end audio such as computers and mini-headphones.
	Phono. A common name for the physical extruding pin and ring connection. Widely used for video or audio signals, it is also called RCA. Can be converted to a BNC plug with an adaptor.
	RCA - See 'Phono'.
	RGB Component. A high-end way of sending computer signals to monitors and displays via five separate component signals: red, green, blue, horizontal (grey cable) and vertical (black cable). Physically, the connectors can be phono or BNC types.
	SCART. A common way of connecting TV and video equipment. The SCART will send video and audio signals. Unless a SCART is bi-directional, it will only send signals in one direction. For example, a SCART-IN can be used to send a signal in to a display but not to get a signal out of a satellite box. SCART to Phono (video and stereo audio) and SCART to S-VHS adaptors are available. Unless a SCART socket is wired for S-VHS, a SCART to S-VHS adaptor will only give a black and white picture.
	S-Video. Separated-Video. A 4-pin connector that sends video only signals in separate luminance (brightness) and chrominance (colour) components. Better than composite, it can be used to send signals over longer distances.
	UDI. Unified Display Interface. Designed to unify computer monitors and general consumer electronics displays (take that as TVs). Now that TVs are getting higher definition, this yet to be introduced interface should be comfortable as a PC connector as well as a TV connection. It carries video only, but is designed to be compatible with HDMI and DVI. Should carry even higher bandwidth than HDMI and has content protection. Rivalled by DisplayPort which is also in development.
	VGA. See '15-pin D-sub'.
Compatibility of Digital and Analogue Computer Connections
DVI-D socket DVI-I socket DFP socket VGA socket DVI-D plug Yes Yes With adaptor No DVI-I plug With adaptor Yes With adaptor With adaptor DFP plug With adaptor With adaptor Yes No VGA plug No With adaptor No Yes