Dahua Technology DH-XVR71 H-4K-I2 Series, Руководство пользователя

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User’s Manual
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If the distance is too long, you should use twisted pair cable, and you can add video compensation
devices or use optical fiber to ensure video quality.
You should keep the video signal away from the strong electromagnetic interference, especially the
high tension current.
Keep connection lugs in well contact
The signal line and shielded wire should be fixed firmly and in well connection. Avoid dry joint, lap
welding, and oxidation.
4.2.2 Video Output
Video output includes a BNC (PAL/NTSC1.0 V
P-P
, 75 Ω) output, a VGA output, and HDMI output. System
supports BNC, VGA and HDMI output at the same time.
When you are using pc-type monitor to replace the monitor, pay attention to the following points:

To defer aging, do not allow the pc monitor to run for a long time.

Regular demagnetization will keep device maintain proper status.

Keep it away from strong electromagnetic interference devices.
Using TV as video output device is not a reliable substitution method. You also need to reduce the
working hour and control the interference from power supply and other devices. The low quality TV
may result in device damage.
4.2.3 Audio Input
This series of products audio input port adopt BNC port.
Due to high impedance of audio input, use active sound pick-up.
Audio transmission is similar to video transmission. Try to avoid interference, dry joint, loose contact
and it shall be away from high tension current.
4.2.4 Audio Output
The audio output signal parameter is usually over 200 mv 1 KΩ (BNC or RCA). It can directly connect to
low impedance earphone, active sound box or amplifier-drive audio output device.
If the sound box and the pick-up cannot be separated spatially, it is easy to arouse squeaking. In this
case you can adopt the following measures:

Use better sound pick-up with better directing property.

Reduce the volume of the sound box.

Using more sound-absorbing materials in decoration can reduce voice echo and improve
acoustics environment.

Adjust the layout of speaker and pickup to reduce squeaking.