Product specifications, parameters, functions of the device can change without notice!
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IDENTIVISION IP NVR INSTALLATION GUIDE
2.7 Audio and video input and output connections
2.7.1 Video input connections
The video input port is BNC connector plug. The demand of input signal is PAL/NTSC BNC(1.0VP-P,75Ω).
The video signal must be accorded with the state standard which has the high signal to noise ratio, low
aberration and low interference. The image must be clear and has natural color in the appropriate
brightness.
Insure the vidicon signal stable and credible
The vidicon should be installed in the appropriate location where is away from backlighting and low
illumination or adopts the better backlighting and low illumination compensation.
The ground and power supply of the vidicon and the DVR should be shared and stable.
Insure the transmission line stable and credible
The video transmission line should adopt high quality coaxial pair which is chosen by the transmission
distance. If the transmission distance is too far, it should adopt shielded twisted pair, video compensation
equipment and transmit by fiber to insure the signal quality.
The video signal line should be away from the electro magnetic Interference and other equipments signal
lines. The high voltage current should be avoided especially.
Insure the connection stable and credible
The signal and shield lines should be firm and connected credible which avoid false and joint welding and
oxidation.
2.7.2 Video output connections and options
The video output is divided into PAL/NTSC BNC(1.0V
P-P
,75Ω) and VGA output(selective configuration).
When replace the monitor by the computer display, there are some issues to notice.
1
、
Do not stay in the turn-on state for a long time.
2
、
Keep the computer display normal working by demagnetizing regularly.
3
、
Stay away from the electro magnetic Interference.
TV is not a credible replacement as a video output. It demands reducing the use time and control the power
supply and the interference introduced by the nearby equipments strictly. The creepage of low quality TV
can lead to the damage of other equipments.
2.7.3 Audio signal input
Audio port is RCA connection.
The input impedance is high so the tone arm must be active.
The audio signal line should be firm and away from the electro magnetic Interference and connected
credible which avoid false and joint welding and oxidation. The high voltage current should be avoided
especially.
2.7.4 Audio signal output
Commonly the output parameter of DVR audio signal is greater than 200mv 1KΩ(RCA) which can connect
the low impedance earphone and active sound box or other audio output equipments through power
amplifier. If the sound box and the tone arm can not be isolated, howling phenomena is often existed. There
are some methods to deal with the above phenomena.
Adopt better directional tone arm.
Adjust the sound box volume to be under the threshold that produces the howling phenomena.
Use fitment materials that absorb the sound to reduce reflection of the sound.
Adjust the layout of the sound box and the tone arm.
