【 Weak current College 】 TV car audio system-Power By 【 China power house network 】

Television ob van is a complete TV scene shooting and production and transmission unit, is a miniature of the TV. Because of its flexibility, effectiveness, flexibility and versatility, etc., has now been widely adopted by various television stations, a subject other than news, Studio performances and sporting events, and so on various occasions TV programs on-site production and broadcast of an important means. OB van system include: cameras, switching stations, subtitles, video system; audio synthesis, call intercom, audio system and power distribution systems, etc. This article to Zhanjiang city television ob van, for example on ob van audio system.

A system design

OB vehicle audio system design by work habits General design for two jidiao tone, car Tuning Tuning for level 2. The so-called two jidiao tone, that is, programs on site audio synthesis, and then transfer the cartridge and audio integrated cable and audio cable to the OB van on a mixer, through audio distribution amplifier, together with the video signal sent to on-board recorders or give microwave transmission transmit or send optical transmitter fibre to audio signal back to the bench, while giving back to the car, Director, technology, audio zone za.
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Figure 1 as an audio system principle work block diagram.
This field tuning, more intuitive and reliable IK to grasp the situation. Commonly used in large gala and sports scene.
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Figure 2-ob van audio system on the circuit diagram. Second audio system of work process

Following on the audio system of work process.

1. the transfer box and integrated cable 500) this.width = 500 "border = 0 dypop =" click here to browse pictures in a new window ">
Gala normally only need to use an audio cable to connect to the sound mixer from level ob van audio interface is working properly, but athletic competition involves on-site interpretation must be integrated with transfer boxes and cables.

Audio integrated cable, as the name implies is that a multi-channel audio signal transmission cable. It generally includes the audio balance transmission lines, video cable, power cord, phone cord, etc. It is with external signal Exchange through the transfer box.

Switching input and output signal box as shown in Figure 3.

In sport competitions of on-site production, field synthesis of audio signal generally consists of a main one slave feed transfer box, sometimes in large international conferences have synthesized signal, you need to transfer international channel (it is also a main one slave). This transfer case on 4 audio inputs. Sometimes the scene also need ob vans on the signal (usually a VTR on like sound), so there are two channel audio to export.

For sports scene interpretation or live program that guides according to the picture for explanation, recording sound under Picture options, and you want to know exactly what the start and end time, so the transfer box to have the video output is used for monitoring, generally there are two ways.

Sports competitions in the power of two jidiao tone, are provided by ob van. After ob van out of power, because of the isolation transformer and parameters of the voltage regulator, voltage stable reliable, is conducive to the stability of the machinery and equipment. Level mixer power can usually be removed from the transfer box.

Call system in television broadcast system is very important, Director of photography at the request of the lens, on the audio and lighting requirements as well as departmental coordination through the intercom system. On-site tuner and lighting Division and ob van calls rely on transfer box interface.

Transfer box with power supply, to show whether the transmission on ob vans. Through specialized power connector for devices such as a mixer, monitor the transmission. Transfer the cartridge has a multi-core cables go through its interface, and integrated cable connection.

Audio integrated cable is multicore cables, it contains a power cord, and contains audio, video, talkback line, etc. Audio integrated cable outsourcing layer employing special rubber, strong tensile, compression, and a certain degree of ductility and flexibility, in practice it is easier to control.

2. relay car audio

OB vans on the mixing console, generally the level mixer has processed good signal, after simple compressor, equalization processed through audio distribution amplifier the signal respectively to listen, video equipment and optical transmitter, etc.

A mixer for ob van, you must decide which according to the actual situation, and the way it's input must be a separate line and microphone mouth through the sound mixer Panel select the input signal. Line and separated from the cylinder to mouth as many line signals and microphone signals connect directly with a mixer.

The index you want to compare the sound mixer, a VU meter or PPM table monitor, you must also have oscillation signal and listening socket. Listening can be divided into audio area, district and technical area, and the District of listening to their own control.

Car audio mixing console in addition to the input signal outside the car, also accept car playback equipment and recorders, audio signals, car standing there CD playback device, MD machine, etc. For video digital ob van, audio and video are not synchronized, will result in serious audio splitter can set a delay before compensation.

Taking into account the mixer may also appear in the event of failure of 1-16, audio equipment as emergency backup, ensuring always have the audio output.

3. jumper interposer

For ob van, in the limited space must have a variety of complete system features that rely on large, full equipment is not practical or economical. For an audio mixer, way of the heart cannot be too much, which caused many signal will not be able to connect directly with a mixer, must undergo some surfacePlate heat transfer of jumpers. As shown in Figure 4, normally within the upper and lower socket is connected, when you insert a plug, the signal is disconnected and removed. Jumper transfer design of ingenious will give a lot of work, but also save a lot of equipment investment, easier to inspect equipment is good or bad and emergency treatment.
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Figure 2 shows the Zhanjiang ob truck audio system, mainly designed for second-level tuning, sound mixer for a total of 24-channel input MIDASVenice240. 16-channel microphone input through the camera two microphone mouth and base station is connected to the mixer, so in General a mixer can also be used as a level one. 20-channel line inputs with 3 VCR, CD player, MD player, four-channel external signal and two-channel microphone amplifier connection. Since there are 12-channel microphone input is inserted into the line again, so the sound mixer to choose according to the actual situation. In Figure 4 jumpers go interface, all equipment import and export audio signal can be removed or reload, car jumper design reasonable, will give the work a lot easier. Left of Figure 2 is a four-channel external signal interface and integrated cable interface, input and output of I/O interface board. Also equipped with two passive audio isolator, in the encounter audio interference, connected to the isolator can basically be eliminate interference.