It simply plugs in devices (TV

Digital terrestrial TV

Two major types of broadcasting exist for television; the so-called analogue and digital television. The analogue television appeared the first. This is widely spread around the world. However, this type of diffusion is ageing and not very innovative.
For this reason analogue television is currently tending to disappear to give way to digital television. Digital television is largely based on analogue televisio......

s) that have analog audio/video functions using a 21~pin connector.

There are three types of connectors : the socket on the devices, the male/male cord and the extension cord.
Peritel connectors are more often found on equipment marketed in Europe.

Today analogue television is being replaced by digital television; It allows access to high definition; the Péritel, which had been compulsory on televisions since 1980, is replaced by HDMI

HDMI

HDMI is a fully digital audio/video interface that transmits uncompressed encrypted streams. HDMI is used to connect an audio/video source (DVD player, Blu-ray player, computer or game console) to a high-definition TV.
HDMI supports all video formats, including standard, improved, high-definition definition and multichannel sound. HDMI encapsulanses video data by TMDS. Initially, the maximum HDMI transmission......

. The peritel has not existed since the end of 2014.

Pin 8 uses the slow switching signal from the source, which switches the video input and the type of video signals to be operated :

~ 0 V means \no signal\ or internal signal (example : running THE TV

Digital terrestrial TV

Two major types of broadcasting exist for television; the so-called analogue and digital television. The analogue television appeared the first. This is widely spread around the world. However, this type of diffusion is ageing and not very innovative.
For this reason analogue television is currently tending to disappear to give way to digital television. Digital television is largely based on analogue televisio......

);
~ 6 V means : selection of the auxiliary audio/video input and 16 : 9 image format (technical evolution after the original standard);
~ '12 V' means : selection of the auxiliary audio/video input and 4/3 format.

Pin 16 is a signal from the source, which indicates whether the signal is in RVB or composite :
~ 0 V to 0.4 V composite;
~ 1 V to 3 V (nominal 1 V crest) RVB only.
The 16 pin is referred to as the quick switching :
It can be used to embed the RGB signal within another video signal : Teletext and captioning.
The video bandwidth allowed on the rapid switch is 6 MHz.

The use of this socket is of interest only for screens that can be satisfied with a low definition (about 800 × 600).
For higher~definition screens, it's useful for plugging in all products without an HDMI

HDMI

HDMI is a fully digital audio/video interface that transmits uncompressed encrypted streams. HDMI is used to connect an audio/video source (DVD player, Blu-ray player, computer or game console) to a high-definition TV.
HDMI supports all video formats, including standard, improved, high-definition definition and multichannel sound. HDMI encapsulanses video data by TMDS. Initially, the maximum HDMI transmission......

socket (for example, an analog VCR, VHS type).
For high~definition digital devices, it is necessary to verify that they have an HDMI

HDMI

HDMI is a fully digital audio/video interface that transmits uncompressed encrypted streams. HDMI is used to connect an audio/video source (DVD player, Blu-ray player, computer or game console) to a high-definition TV.
HDMI supports all video formats, including standard, improved, high-definition definition and multichannel sound. HDMI encapsulanses video data by TMDS. Initially, the maximum HDMI transmission......

output (DVD

The CD player

It's a drive optical drive that reads through a laser diode optical discs called CDs or CD, be it CD or computer CD-ROM. When it is used to listen to music CDs, the CD player can be integrated into various types of portable devices or servants, to a radio handset, etc. It can also be a separate, portable device or domestic, to connect to a channel Hi-Fi, an audio amplifier or headphones.
Computer, the CD playe......

player, games console with disc player, digital receiver), because the connection by Péritel brings losses :

Beyond three metres, an extender cord cannot effectively convey the weak and multiple analog signals it operates without disruption.
Without specific processing (video amplifier, audio filter) and therefore non~compliance with the original standard, longer links should not be recommended.