This is by far the most common kind of audio/video connection terminal. This two-wire connection terminal was invented by RCA Recording Company as early as the era of radio. There is also a more old-fashioned and strange name called "turntable" connector. The RCA terminal uses a coaxial transmission signal, the central axis is used to transmit signals, and the contact layer on the outer edge of a circle is used to ground, and can also be used to transmit digital audio signals and analog video signals. RCA audio terminals are generally labeled in pairs with different colors: the right channel is red (the letter "R" means "right" or "red"); the left channel is black or white. Sometimes, the center and surround channel cables will be marked with other colors to facilitate the differentiation of wiring, but all RCA connectors in the entire system are the same in electrical performance. Generally speaking, RCA stereo audio lines are a group of left and right channels, and each channel looks like a line.
XLR balanced terminal
This is a three-wire connection terminal, the three wires are positive, negative and shielding. XLR is called "balanced terminal" and "microphone plug". Generally speaking, it is used in professional or broadcast television fields, but it is also used in some Hi-End consumer equipment to transmit signals between the pre-amplifier and the post-amplifier. In terms of connection, the three-wire XLR plug outputs audio signals, while the three-wire jack inputs audio signals. The advantage of the XLR terminal is to balance the linear transmission signal, which can greatly reduce the noise and hum generated in the audio signal due to electromagnetic and radio frequency interference during the operation of the electronic system when the audio signal is transmitted over a long distance. However, in general consumer household appliances, the advantages of XLR transmission are not very obvious.
Phone/Mini-phone headphone terminal
The design of the standard 1/4 inch (6.35mm) diameter earphone plug and jack comes from the early telephone wiring board. This kind of wiring terminal is generally a three-wire structure (divided into left/right channels and grounded) for stereo signal output on AV equipment. Headset plugs and jacks are usually also used in professional or broadcasting equipment. At this time, a two-wire structure (divided into signal and ground) is used to transmit mono signals. Sometimes a three-wire structure (divided into positive, negative and shielding) is used to transmit mono signals in a balanced manner. The small earphone terminal with a diameter of 1/8 inch (3.5mm) is the same as the standard earphone terminal in function, and is mostly used for stereo signal transmission on portable equipment.
Digital Audio Terminal
Coaxial coaxial terminal
According to the SPDIF(Sony-Philips Digital Interface Format, Sony-Philips Digital Interface Format) standard, a wire with the same appearance as the RCA analog audio terminal can also be used to transmit digital audio signals. The coaxial terminal can be used to transmit stereo (CD format) or multi-channel (Dolby Digital/DTS) digital signals, and the plug is generally marked with orange and black. Although any wire that uses an RCA plug can be used to transmit digital audio signals, it is best to use a wire designed specifically for digital audio to achieve the best possible transmission effect, that is, the impedance of the plug and jack should be marked as 75Ω.
Toslink(Optical) fiber optic terminal
The standard of the Toslink fiber optic terminal is the same as the coaxial RCA terminal, which is the SPDIF digital audio format, but the data transmission is not through the fluctuating current, but through the pulsating light wave, using a special optical fiber as the medium. From the output port of the Toslink, you can see red light, which is not a laser and will not be harmful to the human eye. Dirt and dust will hinder the transmission of light waves, so do not touch the connection port with your hands when in use, and put the dust cap on the port when not in use. In addition, the optical fiber line cannot be bent and twisted excessively, otherwise it will cause permanent damage and cannot be used.
AES-EBU(XLR) Digitally Balanced Terminal
This kind of terminal is adopted by "Audio Engineering Society" (AES) and "European Broadcasting Union" (EBU), and the basic design is the same as the XLR balanced terminal for transmitting analog Broadcasting signals. This type of connection is very common in professional audio equipment, but in the home field, it is only used in some super Hi-End stereo and home theater equipment.
Speaker connection audio terminal-spring clip
This type of connection is common in affordable AV receivers, dual-channel amplifiers, and entry-level speakers. It is also very simple to use. Press the spring clip, insert the bare wire end into the wire hole, and loosen the spring clip to clamp the wire end. Because the reeds inside the spring clip are installed very close, there will be electromagnetic contact in a relatively small area. However, it is sufficient for the speaker connection with the maximum output power below 100W.
Multi-purpose wiring plug and socket
This kind of connection method can be applied to almost all speaker cable plugs, such as: tighten the bare wire end, pass through the horizontal hole of the terminal, and then tighten the terminal; Or bend the metal strip of the thread end into a U shape, wind it around the terminal, and then tighten the terminal. Or insert the metal strip of the thread end directly into the hole of the terminal, and then tighten the terminal. If the thread end is a banana plug, just insert it directly into the hole on the front of the terminal.
Banana Plug
The name of this plug comes from its slightly bulging shape. It is very convenient to insert the hole on the front of the multi-purpose socket mentioned above, and a very large contact area can be formed after insertion. This feature makes it preferred to be used in high-power output equipment to connect speakers and receivers/amplifiers. Sometimes you can see banana plugs divided into two groups, called "double banana plugs", but not on all equipment (especially speakers) can be used.
Video terminal
Composite composite video terminal
The appearance of this terminal is the same as the RCA terminal used to transmit analog and digital coaxial signals. The source of its name is because the composite video terminal transmits chrominance (various colors) and luminance (black and white) signals at the same time through a single line, usually the appearance is marked as yellow. In terms of use, as long as it is an RCA plug and a wire that transmits signals in a coaxial manner can be used to transmit composite video signals, but the specially designed 75Ω impedance wire can restore better images, especially when the difference is more obvious in long-distance transmission. This is because the specially designed wire is more able to reduce the influence of impedance mismatch and signal reflection on the image and reduce ghosting. The composite video terminal is the most commonly used, but it is also a video transmission method with low fidelity, so the S video terminal and the color difference video terminal are more suitable when the image restoration quality is required.
S video terminal
Since the S video terminal uses separate lines to transmit the chrominance and luminance signals in the color video signal, the restored image quality is obviously better than the composite video terminal that uses a single line to transmit chrominance and luminance signals at the same time. The S terminal uses a unique four-pin plug (the official name is mini-DIN connector). When using, be sure to make clear the direction and position of the insertion. If you insert it blindly with brute force, you will bend the needle and cause damage to the plug.
Component color difference video terminal
The English name of the color difference video terminal comes from the fact that this terminal separates the video signal into three different basic parts (Component) for transmission. Therefore, the color difference terminal uses three separate signal lines to transmit signals, and the restored signal quality is better than the composite terminal and the S terminal. In terms of appearance, the color difference terminal is the same as the ordinary RCA terminal, but the three wires are combined together, but the signals transmitted by the three wires are completely different. The three groups of signals are: brightness (marked with Y), and color difference signals (marked with Pb and Pr) after removing brightness signals from two of the three primary color signals-blue and red, which are distinguished by green, blue and red respectively at the junction of the three lines. If these three lines are inserted wrong with each other, the picture may not be displayed or strange colors may be displayed. Some DVD players use BNC plug sockets (see RGB H/V video terminals below) for color difference signal transmission.
On some equipment, it can also be seen that the color difference video terminals are marked as "Wideband" (broadband), "HDTV-Ready" (HDTV ready), "HDTV-Capable" (HDTV available), etc. These marks mean that color difference signals can be output from HDTV tuner, progressive scan DVD player, line multiplier or other video processing equipment, and can also be normally displayed on high definition television and. If your TV does not have the function of receiving high-definition signals and progressive scanning signals, even if you use the color difference terminal to input these signals, you will not get any picture quality advantages.
Standard video interface in Europe: SCART
Transmission signal: The SCART interface transmits CVBS signals and interlaced RGB signals. Usually, SCART is used by manufacturers to transmit RGB signals. Since the three primary color signals are transmitted separately, they perform better than S-Video in terms of chromaticity. SCART now only has standards for transmitting 480I/576I interlaced signals.
D video terminal
This terminal is named because its shape is close to the English letter "D". It transmits video signals digitally and is directly input to a video display device with a D video receiving terminal, avoiding the digital-to-analog conversion process in the process of transmitting signals through analog video signal transmission, thus improving the quality of digital video restoration. D terminal is currently divided into D1, D2, D3, D4, D5 a total of 5, the same shape but can be transmitted video signal bandwidth is not the same, the higher the number of transmission bandwidth. D1 can only transmit 480i signals, D2 corresponds to 480i and 480p,D3 corresponds to 480i/480p/1080i,D4 corresponds to 480i/480p/1080i/720p,D5 has the highest specification and can transmit 480i/480p/1080i/720p/1080p
RGB H/V video terminal
"RGB H/V" represents the red, green, and blue video signals plus the horizontal and vertical video signals. This is a transmission method that has long been used on professional video displays and computer displays. Now it is applied to the HDTV field. You can see this on HDTV monitors and projectors (including some models that are not high-definition). This 5-head input port. Generally speaking, RGB H/V output and input terminals all use BNC(Bayonet Neill-Concelman, "Neil-Conseman insert", named after the inventor of this socket) plug jack as shown in the figure. This connector is inserted and tightened, and is mostly used in professional laboratory equipment to provide extremely reliable connection. Sometimes, the RCA connector will also be applied to this connection, for example: from the computer or professional video equipment with RGB H/V terminal output signal, the other end of the signal line with VGA terminal output signal, but this method is relatively high cost.
VGA video terminal
For those who have connected computer monitors to the host computer, VGA, a standard 15-pin D-port terminal, should be familiar. From the principle of signal transmission, VGA terminal and RGB H/V terminal is the same, but the shape is different. In video equipment, the VGA terminal is mostly used for signal output on HDTV tuners, or for signal input on HDTV displays and projectors.
DVI video terminal
The full name of DVI is "Digital Visual Interface, Digital Video Interface". Like VGA and RGB H/V terminals, it is also transplanted from the computer field to household equipment. DVI uses an approximately rectangular 18-pin connector to unidirectionally transmit digital video signals, for example, from an HDTV tuner to an HDTV display. Since DVI connection completely avoids the digital-to-analog conversion process in the process of transmitting signals through analog video signal transmission methods (such as color difference terminals, RGB H/V terminals, VGA terminals and other broadband video connection methods are still analog transmission), it has greater potential to achieve better digital video display quality for fixed pixel plasma, LCD, DLP and other display methods. In some of the latest HDTV equipment, DVI connection mode has been applied. In order to avoid illegal copying of DVI digital signals, HDCP(High-bandwidth Digital Content Protection, Broadband Digital Content Protection) anti-theft copying technology is also adopted on these machines.
Multi-purpose connection terminal
FireWire live wire terminal
The name of this connection, invented by Apple, meets the IEEE 1394 digital interface standard and is now widely used in computers and audio products. Sony calls it "I. Link terminal", and other manufacturers also have various names, such as "DTV Link". This connection method uses a small rectangular 4-pin terminal, digital serial interface, two-way transmission, transmission speed up to 400M per second, used for computers with built-in hard disks, computer audio and video editing systems, digital cameras, or HDTV tuners. In some computer equipment can also see a larger 6-pin wire terminal, while transmitting data and providing power. Before the advent of HDCP anti-theft copying technology, the Firewire terminal was completely disabled on HDTV equipment to prevent illegal copying, but it was heavily used in digital camera connections.
USB Universal Serial Bus Terminal
The full name of USB is "Universal Serial Bus" (Universal Serial Bus). It uses rectangular or rectangular-like terminals and has replaced the old-fashioned 9-pin serial port used in personal computers to a considerable extent. Of course, it is in the field of home theater. In China, it has also been widely used. Rectangular terminals (or Class A terminals) are more common in computer hosts, while terminals similar to rectangles (or Class B terminals) are common in computer peripherals. For the use of audio and video, USB terminals are mostly used as computers, servers, portable MP3 players and computer audio and video recording/editing systems for data input/output transmission.
Ethernet(RJ-45) Ethernet terminal
The external image of this terminal is the same as that of a telephone line plug jack with a larger size: insert it and clamp it tightly, press the plastic reed and pull it out. Ethernet terminals are transplanted from the computer field and are mostly used in home theater equipment with network connection functions, such as receivers, hard disk recorders and digital music servers. Almost every computer/electronics store will have these plugs and wires for sale, and they are already connected.
RS-232 terminal
This 9-pin terminal can be seen on some A/V equipment and is used in conjunction with the DB-9 jack. It is mostly used for the connection between the equipment and the computer for control and data exchange. It is also used as a standard interface for home automatic control systems (such as touch screen controllers).
F-type(antenna) antenna terminal
This terminal is coaxial connection, more common in the receiver and pre-amplifier/tuner, used to connect the FM antenna, receive weak RF RF signal. This kind of terminal has two kinds of plug-in type and screw-in type, the latter can be found in cable television signal lines and indoor antenna equipment.
Telcom(RJ-11) telephone line terminal
In the field of audio and video equipment, this kind of terminal is more common in satellite receivers and hard disk recorders. Their internal modems can dial-up Internet access through this kind of terminal to transmit data such as TV program listings. In the use of ordinary telephone wiring is completely consistent.
Mini-phone micro headphone terminal
The appearance of this terminal is the same as the above-mentioned earphone terminal for stereo analog signal transmission, but it is only a two-wire connection for signal transmission and ground respectively, instead of using three wires for stereo signal transmission like the earphone terminal. This kind of terminal is more common in A/V receiver and pre-amplifier backplane, and the output/input excitation mode of 12V voltage is used to control the power on or off of other peripheral equipment. At the same time, this terminal is also used to transmit infrared remote control signals, so if you use all kinds of equipment is the same manufacturer's products, you can use the remote control to point to one of the machines, while controlling other machines that are inconvenient to operate directly.
HDMI High Definition Multimedia Interface Terminal
The full name of this terminal is "High-Definition Multimedia Interface" (high-definition multimedia interface) terminal, which has not been used in any officially sold products, but it is likely to be a standard connection terminal in the future. For digital video transmission, its basic principle is the same as the DVI terminal are single-wire transmission, but it also transmits stereo and multi-channel digital audio, internal and infrared remote control signals. This 19-pin terminal is significantly smaller than the DVI terminal and looks more like a USB terminal. HDTV displays and source equipment equipped with HDMI terminals (first used in tuners and DVD players) are expected to appear on the market early next year. Through a converter, a device with an HDMI terminal can be backward compatible with a device with a DVI terminal. Of course, such a connection method does not necessarily transmit digital audio signals and control signals as directly connected to the HDMI terminal.