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Multimedia information publication system reconstruction for Guangzhou Digital City

Time: 2017-03-29

I, Demand Analysis:
    1, Project name: Multimedia information publication system
    2, Project build object:
        (1) Broadcasting news or information at real-time, so that audience can watch what they care 
        (2) Effectively deliver and spread the information out to get a better advertisement effect.
        (3) More cost effective compared with the traditional system, but the effect is better.
    3, System Introduction:
        The original system of this digital city adopts directly VGA cable for transmission, VGA cable is kind of coaxial cable, and distance just can reach 5meters, max can reach 30meters after special treatment, but for longer distance there will be serious signal loss which cause the transmission is not real-time and video quality is not good. Besides, the cost of such VGA cable is very expensive, and not convenient to do the cabling. Such being the case, they choose to use our multiple output VGA transmitter and receiver for reconstruction of the system. The system adopt network cable for transmission, which is very easy to install and cost-effective, but with a high quality display effect.

        For digital signal type, you may use our HDMI type extender for solution.

II, System Function:
    1, The system can divided into two parts: video transmission and multimedia public terminals.
    2, Can transmit the local video to multiple locations at the same time
    3, Easy to install, and can support VCD, DVD signals if used together with a video converter.
    4, All the display terminals show the same picture image.
    5, Considering the system compatibility and expand, use a 8x8 video switch system, which is convenient for switch between different video signals.

III, System composition and equipment configuration
    1, Transmission system:
        Use multiple output VGA/audio transmitter is ok if just need to install 20 points at each floor, ladder way, hall and outdoor.
    2, Video display system:
        (1) May use the big screen TV, regular computer monitor, as well as projector, customers can choose the proper one according to the project needs. 
        (2) Can use a video converter if want make it compatible with other type interference, and also can change it into monitoring and video-on-demand systems if needed.
        (3) Physical network system, mainly use video extender and network cable for transmission, for some short distance can connect with VGA cable directly.    
    3. Connection Map: 

     4, Product select 
        (1) VGA-T24 video/audio transmitter(Qty 1unit) 
        The product is designed as 1video/audio input, 24 RJ45 outputs, each RJ45 can connect to a VGA/audio receiver over cat5 cable, and max extension distance is up to 350meters, also there’s a VGA port and AUDIO port for on sender part for local use by user. This product can be widely used in computer and monitor filed, big screen advertisement, education, banks and security system etc 
Product Specification: 
Size: 140mm (L)* 85mm(w)X 32mm(H)   
Weight: 3.5kg
Extension distance: max up to 350m
Cable Type: CAT5, CAT5E, CAT6, UTP, CAT5E and UTP suggested
Video type:  VGA, SVGA, XGA, SXGA, UXGA, LCD
Video Standard: 0.7Vpp
Audio Type: 1Vpp
Connector: HDB15, RJ45
System Support: No
Sender Power: DC 12V 10W

(2) VGA-100HD video/audio receiver (Qty: 20units)

    It can extend Audio and Video signal of the computer max up to 600m through a single cat5e cable. The product can be widely used in computer and monitor field, large screen advertisement, education, bank and industry etc.

Extension distance






I/O connector 


Local output


Input Level range


Input level difference


Input independence


Output independence


Return loss


Max DC compensation




Interface type


Video standard



300MHz(-3 dB) full-load
0-10MHz  +0.1dB
0-130MHz  +6dB到-0.8 dB





Operation temperature


Storage temperature




(3) SP-2 VGA splitter 

Model: SP-2
Interface: input 15PIN HDB      output 2*15PIN HDB
LED indicator: Power LED 
VGA  bandwidth: 250Mhz 
VGA resolution: max 1920*1440/60Hz
Signal type: VGA, SVGA, Multisync
Transmission distance:  50meters
Power: DC9V/300-500mA
Casing: Metal 
Weight: 320g
Size: 145mm*102mm*40mm
(4)VGA video/audio matrix switch 

Bandwidth: 250MHz (-3dB) full loaded
0-10MHz shows +0.1dB to -0.1dB
0-30MHz shows +0.5dB to -0.5dB
Brightness and chroma disturbance: -50dB@5MHz,-45dB@10MHz
Switch speed: 200ns (longest time)
Differential phase error: 0.1%,3.8-4.43MHz
Differential increase error: 0.1%,3.8-4.43MHz
Biggest transmission time delay: (+1ns) 5ns
Video input: 
Signal type: VGA signal
Connection type: VGA15HDF
Min input voltage: 0.5Vp-p
Max input voltage: 2.0Vp-p
I/O Impedance: 75Ω
Echo loss: -30dB@5MHz
Max DC compensation: 1.5V
Synchronized phase-lock: 0.3V-0.4Vp-p
Video output: 
Signal type: VGA signal
Connection type: VGA15HDF
Min input voltage: 0.5Vp-p
Max input voltage: 2.0Vp-p
I/O Impedance: 75Ω
Echo loss: -30dB@5MHz
Max DC compensation: +5Mv-0
Control category: 
It has RD-232 controlling agreement, infrared remote control, manual kneading board control, power failure protection function.
Control port: RS-232, 9 pins COM connector
Baud rate: 9600/4800/2400
Data position: 8
Stop position: 1
Verification position: No
Controlling structure: 2=TX,3=RX,5=GND
Power supply: 220V/50Hz
Power: 20W
Installation: it has standard cabinet installation shelf
The average time when it does not have breakdown is 30000h.

IV, Cabling and Attentions: 
    Users can do the cabling according to project’s actual needs, and we suggest to select the pure copper cat6 cable for the system, do not use the cheap but with bad quality cable that will affect the video display quality. Judging if the cable is good or bad, user may test the resistance of each wire, normally the resistance of qualified wire should not be over 30ohm. Besides, when do the cabling, please try to avoid the strong electricity and high interference area, if there’s electricity wire that can not avoid then must use the STP cable and keep a distance of 30cm parallel and 20cm crossly from them.
V, Design Policy:
Advanced Technology:
    The system adopts the advanced technology and components, which will provide the customer a solution with most performance price ratio.
    Considering the future development and change, HDMI extender, signal source and display equipments provide the most compatible ability in HDMI protocol and HDCP. 
    We adopt the anti-lightning design in order to avoid the damage that may caused by this.
Simple and Practical:
    It is one of the factors to judge if one system is simple and practical. Our products are easy to install, performance is very stable, and convenient for users to maintain. 
    Meet the user’s requirement with minimized quantity of devices.

VI: Service and Support:
    We have professional technical support team to support you if you meet any problems, and we also can provide the free technical training in order to make the user get familiar with the system much faster

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