Cable Encyclopedia

Cinch (RCA)

Cinch (RCA) is a widespread, strictly speaking incorrect term for non-standardized plug-in connectors (see the following drawing) for transmitting electrical signals mainly to coaxial cables. No screen is necessary in seldom cases, power supply, loud speaker connection or the connection of consumer devices (stereo, television, etc.)A single line pair is frequently used.

Cinch /RCA plug (Grafik 1), Cinch / RCA socket (Grafik 2):


These plug-in connectors are used especially in the home audio and video area (audio visual media), where uniform colour coding is used:

Colour coding in the video area:

YUV = Yellow: Composite Video (YUV)

RGB = Red: Pr (Component Video, colour difference)

Green: Y (Component Video, brightness)

Blue: Pb (Component Video, colour difference)

Colour coding in the audio area:

Standard =

white: Left analog channel

(occasionally also black or grey)

red: Right analog channel

Special forms =

orange: Digital-Audio (S/P-DIF)

black: Subwoofer or center channel

grey: Loudspeaker (seldom)

Cable which has four equal connections is sometimes used for connecting audio devices which can also record to cover both the inputs and outputs of the device in stereo.

white: Left channel for playback

red: Right channel for playback

black: Left channel for record

Yellow: Right channel for record


DisplayPort is a universal and license-free connection standard from VESA for transmitting picture and sound signals. The main areas of use are for the connection of screens and televisions to computers, DVD players and similar devices.

The DisplayPort plugs are considerable smaller that D-Sub and DVI plugs and there-fore allow easy integration of more than two plug-in connections to graphic cards so that they are better for portable display devices, such as notebooks, for example.

Optional locking is also planned, unlike the competing HDMI plug (see the following drawing):


DisplayPort 1.1 allows compatibility with VGA, DVI and HDMI so that connection via a reasonable priced adapter is possible. A few graphic card manufacturers achieve this with a trick which is already placed on the graphic card and not only after the actual output itself: If the graphic card recognises that a model with DisplayPort is attached to the device, the signals will also be issued in this format. If an adapter is used on an HDMI for example, a signal is given to the card to switch over to HDMI-output.DisplayPort supports encrypting by using HDCP and also the intrinsic encrypting standard DPCP (DisplayPort Content Protection).The cable length for video transmission with a screen resolution of 1920 x 1080 is a minimum of 15m.

DisplayPort supports encrypting by using HDCP and also the intrinsic encrypting standard DPCP (DisplayPort Content Protection).

The cable length for video transmission with a screen resolution of 1920 x 1080 is a minimum of 15m.

Printer cables can be received on the market both for serial and parallel interfaces where the parallel interface also offers the possibility of bi-directional data transmissi-on. The IEEE-1284 standard was defined for this bi-directional parallel interface and the matching cables.

IEEE 1284 – Standard Signalling Method for a Bi-directional Parallel Peripheral Interface for Personal Computers, was amended in 2000. The IEEE 1284 defines a double, screened 36 strand „Twisted Pair“ cable with 18 stranded pairs and also their configuration.

Three different types of plugs area usually used:

Type A – the 25 pole D-Sub plug. It was introduced in 981 by IBM with the PC for space saving reasons. The main disadvantage, compared to the 36 pole „Centronics plug“ used up to present date is that a corresponding twisted pair return is not availa-ble for each signal line.


D-Sub 25 Plug (left), D-Sub 25 Socket (right)

Type B – the 36 pole „Centronics“ plug (official, but seldom used name: „Micro Ribbon Connector“). This type of plug was used exclusively before the introduction of IBM-PCs.


Centronics 36pin Plug (left), Centronics 36pin Socket (right)

Type C – an electrically improved and more compact variation of the Centronic plug, also 36 pole with „snap on locking“, also called „Mini Centronics“. This type has not established itself however.


Mini Centronics 36pin Plug

The theoretically maximum cable length is approximately 12 meters although special cables allow a length of 30 meters.

Digital Visual Interface (DVI)

Digital Visual Interface (DVI) is an interface for transmitting video data. DVI in the computer area developed into a standard for connecting TFT monitors to the graphic card of a computer. There are televisions in the area of games electronics which process signals from digital sources. Such as computers or DVD players via DVI input signals.

These can transmit analog (DVI-A, seldom used), analog and digital (DVI-I), or only digital (DVI-D) signals, depending on the pin configuration of a DVI connection. Two digital signals can also be transmitted at the same time (Dual-Link, 24+1 PIN / 24+5 PIN), so that higher resolutions (QXGA, max 2560 x 1600 pixels, for example) are possible. There is a maximum of 1915 • 1436 pixels with 4:3 resolutions for a single link cable and a picture refreshment rate of 60 Hz. The maximum resolution for single link cables is therefore 1600 • 1200 pixels (UXGA) for this reason.

There are usually quality advantages from digital data transmission compared to an analog connection with a VGA- or SCART cable. Precisely two signal conversions are necessary for the latter mentioned cable types (not necessary for digital monitors): from digital to analog at the video output and back from analog to digital in the monitor.

A VGA screen can be operated by using a purely passive adapter can be operated at a socket where there is a combined signal (DVI-I, 18+5 PIN / 24+5 PIN).

The maximum length of line for connection to a DVI terminal unit (monitor) depends on the quality of the connection line and also on the quality of the terminal unit howe-ver. A maximum line length of 5–10 meters usually has to be observed. A DVI amplifier has to be used if there is a greater distance. The picture will be more out of focus otherwise for analog transmission: the connection will fail completely at some time or other for digital transmission.

The audio signal is not transmitted with a connection consisting of HDMI to DVI. A separate connection (via Cinch/RCA, for example) is necessary here.

Here is an overview of the most frequently used DVI plugs and sockets:


DVI-D (18+1) Single Link Plug (left), DVI-D (18+1) Single Link Socket (right)


DVI-D (24+1) Dual Link Plug (left), DVI-D (24+1) Dual Link Socket (right)


DVI-I(18+5) Single Link Plug (left), DVI-I(18+5) Single Link Socket (right)


DVI-I(24+5) Dual Link Plug (left), DVI-I(24+5) Dual Link Socket (right)


FireWire, also known as i.Link or IEEE 1394, is a series interface developed by Apple. The FireWire interface is mainly used for quick data exchange between computers and multimedia or other terminal devices, but is also used in industrial and car electronics.

FireWire is used nowadays, especially for transmitting digital pictures (industrial cameras, for example) or videos (DV camcorder, for example) to a PC and also for connecting external mass storage devices such as DVD burners, hard disks, etc.

The new nine pole FireWire 800 (1394b) is necessary to be able to use the data trans-mission rates of modern hard disks (over 70 MB/s with modern 300 GB models) also in external housings, since the conventional FireWire 400 (1394a) is limited to 400 Mbit/s. The external SATA interface is a quicker alternative to FireWire 800.

Here is an overview of the plugs and sockets used:

FireWire IEE


E1394 4pin Plug (left), FireWire IEEE1394 4pin Socket (right)


FireWire IEEE1394 6pin Plug (left), FireWire IEEE1394 6pin Socket (right)


Ribbon cable is a cable with one, or several strands where the strands are not grou-ped together in a circular form but are placed parallel to each other. The construction type of this cable is known internationally as Flat Flex Cable or FFC. It is frequently used for connecting electronic components in computers.

Multi-strand ribbon cable has the advantage that a large number of strands can be connected with little effort to a pin-type plug in connector.

Overview of pin-type plug-in connectors used frequently in the PC area:

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34pin IDC Pfostenplug (left), 40pin IDC Pfostenplug (right)


50pin IDC Pfostenplug

The 34 pin version was/is used for connecting floppy drives. The 40 pin version is frequently used for connecting ATA hard disks. The 50 pin version is not used so often in the home user PC area.

A light grey PVC material is normally used, where a red or a black edge identifies the first conductor. There is also colour-coded ribbon cable where the adjacent strands have 10 different colours in accordance with DIN IEC 62. The colours of larger ribbon cables repeat in accordance with the corresponding number of strands.

The number of strands ranges from 8 pole to 96 pole. The distance between poles can be from 0.5 mm to 2.54 mm. The most frequently used pattern size is 1.27 mm (0.05“), so that a connection can be easily made to double rowed pin-type connectors for a 2.54 mm multipoint strip.

Ribbon cables can also be provided with screening. Usually an aluminium or copper foil which is wound round.

Ribbon cables have been replaced in the last few years partly by round cables, for aerodynamic reasons, since ribbon cable has a much greater influence on air flow in the housing than round cable.


HDMI (High Definition Multimedia Interface) is an interface for transmitting digital audio and video data und video data which was mainly developed for connection to devices from the Home Video Area (televisions/recorders, set top boxes, camcorders and SAT/cable receivers, for example). The HDMI is downwards compatible to established DVI (Digital Visual Interface). This means that an HDMI-DVI adapter cable can connect a DVD player with an HDMI output to a projector with a DVI input, for example.

It is important for all HDMI and DVI connections that both connected components (hardware/device/interface) are provided with HDCP copy protection. Transmission of encrypted, digital video data according to this standard is not possible without HDCP!
PLEASE NOTE ! DVI has existed in the computer area for some time – without HDCP however. Many projectors and also a few plasma TV devices come from the computer area and have therefore not implemented HDCP.
HDMI has been continuously developed in recent years. This reflects in the states of the corresponding versions: HDMI 1.0, HDMI 1.1, HDMI 1.2, HDMI 1.2a, HDMI 1.3 and now currently HDMI 1.3b. HDMI 1.3 doubles the band width of the data rate from previously 4.5 Gbit/s (165 Mhz) to 10.2 Gbit/s (340 Mhz) compared to the previous version 1.2. Another plug type has been established with the introduction of HDMI 1.3.


HDMI Typ A Plug (left), Mini HDMI Typ C Plug (right)

The greatest confusion is with 1080p (full HD). Since 1080p was also a topic in the media with the introduction of HDMI 1.3 onto the market, several people have the impression that HDMI 1.3 is required for 1080p. In fact both these terms have nothing to do with each other. 1080p was already a part of the HDMI specifications already in Version 1.0. Additional data rates were introduced with HDMI 1.3 which were above those of 1080p.

The problem of possible data losses in longer cable lengths –usually after approxi-mately 3-5 meters – was already a topic when HDMI 1.3b was introduced. There are factors here which influence the signal quality which have mainly to do with the cable: the performance of the HDMI interface in transmitting and receiving devices and also the transfer rate of the signal also play a role. The higher the latter is, the shorter the „non problematic“ cable length is. If a 4.95 Gbit/s signal could be transmitted with a previous HDMI with a cable length of up to 10 meters, for example, this length shortens now with the HDMI 1.3b to only 5 meters.

Important: All existing HDMI cables also transmit data in accordance with HDMI 1.3b. This is only guaranteed up to 4.95 Gbit/s however, in other words slightly less than half of the maximum data rate of the HDMI 1.3b. The following therefore has to be taken into consideration: HDMI 1.3 defines the maximum data rate but it does not increase the data rate of a given signal. An existing 1080p signal transmitted with HDMI 1.3b will continue to run with HDMI 1.3b – with the same quality and the same cable length. The quality of the cable will start to be decisive only when the connected components replace the new technical improvements possible with HDMI 1.3b to send correspondingly higher synchronized signals.

Jack Plugs

Jack plugs and sockets are internationally widespread. They are used, for example, for relaying audio signals or for connection to a mains unit for the power supply to a compact device. Jack plugs are very often used for connecting headphones. They are sometimes used for transmitting digital signals for control purposes.

Jack plugs are made with varying shaft diameters:

· 2.5 mm (seldom), used for especially compact devices such as headsets for cell

telephones. They are also use for data transmission between some pocket calcu lators or for cable releases for photographic equipment. This plug size is known as a „micro plug“.

· 3.5 mm, usually for portable devices (MP3 players, sound cards and small head phones). Is also known as a „micro plug“.

· 6.35 mm, for stereo systems and practically all devices from the music production, such as mixing desks, effect devices, synthesizers, keyboards, E pianos, E guitars and guitar amplifiers. They tolerate sufficient mechanical load and have a large contact surface.

Various adapters are available on the market to connect devices with the varying con-nection sockets by using a single cable. These are usually pushed on or screwed on. One should always try to avoid using adapters wherever necessary. However, since the number of contacts which are often faulty anyhow is increased by the adapter so that data transmission becomes worse.

The jack plug types with two (Mono), three (Stereo) and four (Stereo + extra) contacts. The stereo plug with the extra function is a variation of the stereo plug. Some multi channel contacts for PC and cameras use these types of 4 pole connec-tions because of space problems.


Mono-Plug (2-pole): Sig = (sound)signalGND = ground (return line)


Stereo-Plug (3-pole): L = Left sound signal, R = Right sound signal, GND = common ground (return line)


Stereo-Plug with extra function (4-pole): L = Left sound signalR = Right sound signal, AUX = extra signal,

GND = common ground (return line)

Coaxial cables

Coaxial cables, abbreviation: Coaxial cables are double poled cables with a concen-tric construction. They consist of an interior conductor (also known as the core), where a fitted exterior conductor network surrounds interior conductor at a constant distance. The surrounding space consists of an insulator or dielectric material.

Flexible coaxial cables have cable screens and an interior conductor consisting of thin, woven or braided copper wires. The screening can be supplemented with a foil – the woven material can then have a lower amount of coverage. Coaxial cables for higher capacities or higher screening factors usually consist of an interior conductor with a solid wire and an exterior copper conductor (cable screening) with a high degree of coverage. The interior conductor of coaxial cables used in the audio/video area has different diameters (0.43mm to 1.13mm, for example).

Shorter cables are usually used in the area of television and video systems, longer cables are used for connecting radio and television networks. Antennae, transmitters and receivers are connected to each other via coaxial cables in high frequency technology.

The line flow resistance (cable impedance) is the most important parameter of a coaxial cable – it is stated independently from the length of the line and is stated in Ohms. Usual line flow resistances are 50 ohms (general high frequency technology) or 75 ohms (television/SAT technology). The connection of cables to each other and also connection to devices is done by using coaxial plugs which are determined, amongst other items, by the construction and exterior cable diameter and the working frequency range. The following connectors are often used:


· Belling-Lee plugs also designated as IEC 9.5mm plugs (range of use: Cable television, terrestrial plug in antennae connection, for example)

· F plug connectors also known as F plugs (range of use: satellite televisions, for example); the interior conductor is used as a male plug for these devices

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Belling-Lee-Plug (left), F-Plugconnector (right)

Many different coaxial plug connectors for various uses have prevailed in addition to these coaxial plug connectors, such as BNC-, TNC, SMA-, SMB-, SMC-, UHF plug connectors, MCX plugs, etc. for example. These are also used in the field of television and SAT technology.

Patch cables

A Patch cable (engl. to patch – to wire together), also shunt cable or twisted pair cable is a cable type in network technology and telecommunications. Twisted pair cables contain pairs of strands consisting of twisted pairs) of single strands. Patch cables are ready made. The term does not refer to any specific cable standard but to variable, cable connections which are not permanently laid. This is why the strands in the cable consist of pliable copper strands. Contrary to permanently installed cables which con-sist of wires. These can be reconnected according to requirement without a major ef-fort. The cable length is usually approx. 0.3 to 25 m permanently installed connections are usually used for longer lengths. Patch cables can either be wired 1:1 which is also known as straight through or crossed, where they are known as crossover cables.

Four paired cables area used as a matter of preference in current network installa-tion. The ISO/IEC-11801 (2002)E, a new description scheme in the form of XX/YZZ has been introduced, since the old descriptions were not uniform and often lead to confusion or were even contradictory.

We therefore have the following:

· XX for complete screening: U = unscreened, F = foil screened, S = braided screen, SF = braid and foil screen
· Y stands for paired strand screening: U = unscreened, F = foil screened, S = braided screening
· ZZ always stands for TP = twisted pair

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SF/UTP (Screened Foiled Twisted Pair) (left), S/FTP (PIMF) (right)

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U/UTP (Unshielded Twisted Pair) (left), F/UTP (Foiled Twisted Pair) (right)

Categories complying with one respective requirement profile have been introduced for easier classification of the individual cables. Categories 1 and 2 are only informally defined; categories 3 and 4 are no longer commercially relevant (but can still be found in old installations). Here are the most important categories for network installation:

Kategorie 5: Cat 5 cables are the mainly relevant installed basis for working frequen-cies up to 100 MHz. Cables of category 5 are often used in structured cabling of computer networks, such as Fast or Gigabit Ethernet for example.

Kategorie 6: Cat 6 cable is defined by EN50288. Cat 6 cables are used for working frequencies up to 250 MHz. The rate of transmission deteriorates in longer lengths, smaller overlaps do not present any problems, depending on extraneous factors. Fields of application for Cat 6 are speech and data transmission and also multimedia.

Kategorie 7: Cat 6 cables are used for working frequencies up to 600 MHz. A Cat 7 cable satisfies the IEEE 802.3an standard as is therefore suitable for 10 Gigabit Ethernet.


The PS/2 interface (PS/2 connection, PS/2-Port, originally Auxiliary Port) is a globally distributed serial interface for input devices such s keyboard and mouse and less frequently for other pointer devices such as trackball or graphic tablet. It is used in personal computer, for example, but is being more and more displayed by USB.

The PS/2 interface uses a six pole Mini DIN plug. Older desktop PCs usually have two PS/2 sockets one for the mouse (or another pointer device) and one for the keyboard.

The connections are usually colour coded, the keyboard has a violet plug or socket and the mouse has a green plug or socket, for example (see the following illustra-tions).


PS/2 socket for the keyboard


PS/2 socket for the mouse / trackball

The interface is not planned for Hot Plugging, plug-in during on-going operations, for example. Neither the protocol nor the plug-in connectors allow this Hot Plugging. It works in many cases (more for keyboards, rather than mice), the computer or the keyboard could be damaged in theory.

The mouse and the keyboard have different protocols although you have the same plug-in connectors and even the same pin configuration so that the plugs should not be confused. The manufacturers of a few current PC systems have abandoned the PS/2 interface in favour of the Hot Plug capable USB.

Serial Attached SCSI

Serial Attached SCSI (SAS) is a serial computer interface usually not used in the home user area. It is the successor to the existing parallel interfaces. SAS is a point to point connection. This means that the typical SCSI terminals as well as the award of SCSI-ID are no longer necessary. SAS takes over the SATA plug-in connectors although SATA end devices can be used at SAS host controllers and (generally) not vice versa.

The SAS specification defines several plug types where the ‚x‘ has to be replaced in the SFF-xxxx standard by numbers:


SFF-8482 plug for internal connections. (left),
SFF-8484 plug for 4 channel internal connections. (right)


SFF-8487 plug for internal connections. (left),

SFF-8088 plug for 4 channel external connections. (right)


SFF-8470 plug for 4 channel external connections. Also used by Infiniband.

Extra confusion is some caused unfortunately when the manufacturers offer these plugs under a respective brand name such as „MultiLane iPASS“ from the company Molex, instead ofSFF-8087.

The SAS is ideally prepared with RAID configuration for use in large storage systems: Plug and cable specifications are coordinated to Backplane use, on one hand and cheap expanders (hubs/switches) can be used theoretically, to operate up to 16,384 devices in one single SAS system 128 devices per expander in up to 128 expanders), on the other hand. There are two types here, so-called edge expanders for connec-ting the end device and also fan out expander as distribution points. Storage solutions with 2.5“ hard disks and perhaps even smaller format factors are/will be possible in the future because of the compact plugs and thin cables. This means that SAS is the ideal interface concept for ultra compact 1U servers, blade servers and JBOD (Just a Bunch of Disks) memory arrays with little space for cables, plugs and drives.

The following illustration gives an overview of a few connection possibilities:



Serial ATA also abbreviated as SATA (Serial Advanced Technology Attachment) is an interface for desktop systems connected to a PC via hard disks or other peripheral devices. This is the successor to the parallel ATA (PATA) memory interface.

The advantages of SATA for the final user lie in the high reliability of the whole system because of improved air circulation and thermodynamics and also an easier installation.
SATA was mainly created to connect devices inside the computer. The cables and plugs do not have the necessary screening against electromagnetic disturbances for this reason and the plugs do not have the necessary mechanical properties for operation outside a (screened) housing. The standard has special plugs for SATA hard disks and also for the voltage supply. They are also flat, but wider than SATA data plugs.
Cables and plugs were standardised in Version 2 of SATA for external operation („External Serial ATA“, abbreviated as „eSATA“). Power supply to the external device is not possible via the eSATA cable.

eSATA defines screened cables up to a length of two meters and newly shaped plugs and sockets without the L shape of the SATA plugs/sockets to prevent the wrong cable being used externally for internal operations.
The geometry of the eSATA plugs/sockets has an I shape (see the following illus-trations, whereas the SATA plugs and sockets have an L shape. Right angled and left SATA plugs are also available on the market. The most frequent shape for SATA plugs/sockets is the left angled variation.

Overview of SATA and eSATA connectors:


SATA plug(L shape / L type)


SATA plug(L shape / L type), angled


SATA plug(L shape / L type), angled


SATA cables can be up to one meter in length, eSATA cables up to two meters.


SCART ist ein älterer europäischer Standard für Steckverbindungen für Audio- und Video-Geräten wie etwa Fernseher und Videorecorder. Andere Bezeichnungen sind Euro-AV, Euroconnector, Peritelevisons-Verbindung und in Frankreich Péritel. Die Eigenschaften der SCART-Verbindung sind in DIN EN 50049-1 genormt.

Der SCART-Anschluss vereinfacht und vereinheitlicht die Verbindung verschiedener Videogeräte, da er alle nötigen Signale in einem einzigen, mehrpoligen Plug (siehe nachfolgende Abbildung) enthält und einen herstellerübergreifenden Standard bildet.

Abb. Scart Plug (left) und Socket (right):


Da im SCART-Kabel analoge Signale übertragen werden, kann ein gutes Kabel die Bildqualität im Vergleich zu einem billigen erheblich steigern. Das Bild erscheint mit einem guten Kabel insgesamt ruhiger und ausgewogener, in manchen Fällen sogar etwas schärfer. Billige Kabel haben nur eine gemeinsame Abschirmung und keine Einzelabschirmung der Adern. Daher wird insbesondere der Ton durch die benach-barten ungeschirmten Videoleitungen gestört, was sich durch ein teilweise bildinhalts-abhängiges Rauschen bemerkbar macht. Besonders bei digitalen Signalquellen

(z. B.DVD-Player oder Digitalreceiver) fällt dies auf, da diese eine wesentlich bessere Bildqualität liefern als z. B. ein VHS-Videorecorder.

Aufgrund des technischen Fortschritts werden Scart-Anschlüsse mehr und mehr durch moderne digitale Anschlüsse wie beispielsweise HDMI ersetzt.

Serial cables

11 Serial cables (for the RS-232 or EIA-232 interface) are used for data exchange bet-ween computers and peripheral devices (modem, printer, for example). The bits are transmitted over a line one after the other in serial data transmission (serial).

The original standard 25 pole D sub plugs and sockets were used as plug-in con-nections. 9 pole D sub plugs and sockets, frequently called DB 9 or D sub 9, have become established nowadays since many of the 25 strand lines are pure printer and terminal control lines from the electromagnetic era which are not required for most connections made to modern peripheral devices. The 9 pole plug cannot be found in the RS-232 standard for this reason, but in theEIA/TIA574 standard instead.
Other types which are not used so often (D-Sub50 HP and D-Sub68 HP, for example) can be obtained on the market, in addition to these D sub plug types.
D-Sub9 Plug (left), D-Sub9 Socket (right)


D-Sub25 Plug (left), D-Sub25 Socket (right)


D-Sub50 HP Plug (left), D-Sub50 HP Socket (right)


D-Sub68 HP Plug (left), D-Sub68 HP Socket (right)

D-Sub68 HP Plug (left), D-Sub68 HP Socket (right)


Centronics 50pin Plug (left), Centronics 50pin Socket (right)


The „received“ lines must be connected to the „transmitted“ lines in order to connect two devices via a serial interface.

· A 1:1 cable is necessary if this is a connection from the computer with a plug to a modem with a socket, for example.

· The lines (PIN 2 and 3) have to be crossed if this is a connection between two devices of the same kind (two PCs, for example). This type of cable is called a null modem cable.

A maximum cable length of 15m is defined for standard cables according to the original standard because of the cable capacity and the reflected signals.

The reflected signals increasingly impair data transmission with faster transmission rates and longer cable lengths.

Null modem cables are used nowadays where the serial interface is still being used. Set top boxes, such a satellite receivers or DVD playback devices having a serial interface for updating the firmware of the device are typical examples nowadays.


S-Video (also known as Separate Video, Y/C) often wrongly equated with the term S-VHS (Super Video Home System) which designates a video recording format, describes the separate transmission of brightness (luminescence) and colour (chro-matic) information with the properly executed cables and plug-in connectors. It allows a better signal quality as a Composite Video but does not reach the quality of RGB however. Composite and RGB cables often use Cinch plug-in connectors connected to the end devices.

Video signals are generally transmitted via 4 pole Mini-DIN plugs nowadays (also referred to as Hosiden plugs) at a connection resistance of 75 Ohm. The audio connection has to be made via a separate cable (at least Cinch/RCA) since only video signals are transmitted.

S-Video is normally used in Home DVD devices, video recorders and modern games consoles. These plug-in connectors are sometimes used in professional technology and also for computer video cards.

Mini DIN plugs are available in various alternatives with a differing number of pins. The alternatives vary so mush that the various plugs and sockets cannot be confused with each other where damage could possibly occur.

Here is an overview of the frequently used alternatives:


Mini-DIN 4: Apple desktop Bus S-Video (also called Hosiden plugs)


Mini-DIN 6: PS/2 keyboard/mouse plug


Mini-DIN 8: Apple Macintosh and serial interface

Power supply cables

Power supply cablesPower supply cables / IEC power connection cable designates a ready made. Insulated electrical line / cable for domestic use that is usually provided with a coun-try-specific plug, usually with a grounded plug and an IEC power connection cable in the FRG. It is used/they are used to operate electrical devices that do not produce any noticeable heat and can be regularly loaded up to 10 A.
A harmonized system of abbreviations has been developed within Europe by CENELEC (European Committee for Electrotechnical Standardization) for the uniform identification of electrical lines (see table the table on the next page). The type abbreviations for the lines state the construction type and the intended use for the electrical lines in the electrical installation. The identification contains all the necessary information for the construction and optional uses of the line (materials and permitted voltages, for example). National identifications are normal for some line types however.

The abbreviations in Germany for harmonized lines are standardised as:
· DIN VDE 0292 System for abbreviated types of insulated lines
· DIN VDE 0293-308 Colour identification of the strands of cables/lines
and flexible lines
· Standard series DIN VDE 0281 for PVC insulated lines
· Standard series DIN VDE 0282 for rubber insulated lines

Example of a line designation according to European Standard (CENELEC):
H 05 VV – F 3 G 0.75
H = Harmonised type
05 = approved for 300 V voltage
VV = Insulation of the strands and shrouding consisting of plastic (PVC)
F = fine wired (flexible line)
3 = Number of strands
G = with green-yellow ground wire
0.75 = Line cross section in mm2

Different connectors specified in the IEC standard (International Electrotechnical Commission) IEC 60320 are used, depending on the device to be connected.

The following overview shows the most frequent connectors:












Telephone cable

Telephone cable is a usual designation for telecommunications cable. The construc-tion and strand identification of telecommunications cable can be different. The strand descriptions a and b are clearly identifications for the subscriber’s connection line (line between the local exchange and the telephone connection of the service user/subscri-ber in the building). One double strand is used respectively for an analog subscriber connection line (ab interface) and for an ISDN base connection. The respective termi-nals are usually identified at the devices with a or b also with 1a, 1b or 2a and 2b. The main colours of the strands are in the series red, green, grey, yellow and white.
The end connections in the building are connected via a junction box (connection unit) to the subscriber connection line. Two different types are used here:- the TAE socket on one hand and the UAE or IAE socket on the other hand. Cable with suitable plugs which can also be designated as telephone connection cable is required to connect end devices to these sockets. The Telecommunications Connection Unit (TAE) is a plug type used in Germany and partly also in Lichtenstein and Luxemburg with analog telephone connections and an a b interface and with ISDN connections for connecting the NTBA to the connection line.
TAE plugs and sockets either have F or N coding respectively. The F stands for telephone and is planned for the telephone or supply line to the splitter and the NTBA. The N coding stands for Message end device (colloquially also secondary device) and accordingly for all end devices excluding telephones: telephone answering machines, fax machines and modems are included here, for example. The TAE connection is standardised in the DIN 41715. The cable configuration of the TAE plug is not strictly uniform however. TAE plugs from older devices from Siemens, Telekom and from overseas can have another TAE plug-in connector for historical reasons.

A Universal Connection Unit (UAE) is an junction box for end devices in accordance with the RJ standard. The UAE is used for analog and digital communication end devices. UAEs have one or two RJ sockets suitable for RJ45 plugs (also known as Western Plugs or Modular Jacks); RJ11 and RJ12 plugs can also be inserted when re-duction pieces or suitable constructed UAE sockets are used. UAEs with two sockets are either separated from each other are wired in parallel. The contact positions of the sockets can be completely fitted with eight or only with four contacts (the inside four positions; IAE).

An ISDN Connection Unit (IAE) is a special type of UAE. The IAE has one or two four pole RJ11 sockets (also called Western Sockets or Modular Jacks), where only each of the four inside positions is fitted with contacts (8P4C). The connection terminals of the have the descriptions „1a“, „1b“, „2a“ und „2b“ and are therefore specially wired by the UAE 2x8(4). The IAE usually has two sockets wired in parallel.

Here is an overview of the plugs and sockets used:


TAE F Plug (left), RJ11 (6P4C) Plug (right)


TAE N Plug (left), RJ12 (6P4C) Plug (right)


RJ10 (4P4C) Plug (left), RJ12 (8P8C) Plug (right)

USB cable

USB cable is available on the market at the moment in various versions (1.1 & 2.0) and is suitable for many devices such as hard disks, DVD drives, printers, scanners, webcams, mice, keyboard but also for dongles and even cell telephones and cameras.

Four strands are required in a USB cable. Two strands transmit the data, the other two supply the connected device with a voltage of 5 V. The cables must be screened differently according to speed. USB 1.1 cables have less screening function without twisting and are therefore more flexible that Full/High/Super-Speed cables (USB 2.0 / USB 3.0).

Five additional contacts are necessary in the plugs for the latest USB 3.0 version in order to guarantee high data rates.

USB allows transmission of data to a device with 1.5 Mbit/s, 12 Mbit/s or with 480 Mbit/s. The transmission speed in Version 3.0 rises to 5 Gbit/s where USB 3.0 is downwards compatible to the existing USB versions (1.1 & 2.0).

Transmission speed USB Version

Low-Speed (1,5 Mbit/s) 1.1
Full-Speed (12 Mbit/s) 1.1/2.0
High-Speed (480 Mbit/s) 2.0
Super-Speed (5 Gbit/s) 3.0

The lengths of USB cables from the hub to the device are limited to five or three meters. depending on the specifications.

The plugs of a USB cable are designed so that the poles cannot be accidently chan-ged or confused. Flat plugs (type A) and a practically square plug (type B) are used in the direction of the PC/host controller, hub (upstream) and towards the connected end device (Downstream) or the cable is already installed in the end device.

There is a more compact type of plug for end devices with very little space (digital ca-meras, cell telephones, external 2.5“ hard disks, for example) which are designated as Mini- and Micro USB plugs. There are differing construction types here depending on the device manufacturer with many varying connection pins. The colour for the inside part (contact supports) is fixed in the attachment to the USB specification for the Mini/Micro USB plugs:

· Mini/Micro-A (plug and socket) = white

· Mini/Micro -B (socket and plug) = black

· Mini-AB (socket) = grey

Overview of the most frequently used USB plugs:


USB Typ A Plug (left), USB Type B Plug (right)


Mini USB, 5-polig (left), Mini USB, 4-polig (Mitsumi) (right)

USB cable

The VGA-/Monitor Connection is an analog picture transmission standard between graphic cards and display devices (monitors, beamers, for example). „VGA plugs“ are used for cable connections which are equipped with a 15 pole Mini-D-Sub-plug (also D called a Sub-Mini Connection) with three connection rows (type HD15 or also HD D-Sub15, see the following illustration). The VGA is also significant for the resolution of 640 • 480 which is the typical VGA resolution for many.


VGA / Monitor Plug


VGA / Monitor Socket

The output of the graphic card is always a socket (hidden contact pins). The input at the display device can have both genders, depending on the type. This is usually a socket as well (all modern tube and LCD monitors), so that a connection cable is required between two plugs (exposed contact pins).

VGA cables are cleary prone to faults, depending on quality and already with lengths below 5m. A suitable high frequency cable with a coaxial structure is therefore ad-vantageous for the colour channels. VGA is generally only suitable to a limited extent for high resolutions above SXGA (1280x1024 pixels), since fuzziness can appear with analog tube displays and because digitalisation is very demanding in the display controller of the flat screen monitor when LCD monitors are in use.

The DVI interface which can also be used to transmit an analog VGA signal is the digital successor to the VGA interface. An adapter can therefore be used to operate VGA devices at DVI outputs, providing the appropriate signal lines area also supplied with an analog signal (only the case with DVI-I and DVI-A).

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