76 User Manual iTrend SK series 6000 www.trenddvr.com V1302
2.6 Audio and video input and output connections
2.6.1 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.
2.6.2 Video output connections and options
The video output is divided into PAL/NTSC BNC(1.0VP-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.
2.6.3 SDI video input
Only part models of iTrend SK 6000 series support SDI encode for 1080P
2.6.4 Audio signal input
Audio port is BNC 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.
2.6.5 Audio signal output
Commonly the output parameter of DVR audio signal is greater than 200mv 1KΩ
(BNC) 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.
2.7 Alarm input and output connections
Before connecting the device,please pay attention to follow situations:
2.7.1 Alarm input
- Alarm input is grounding alarm input.
- Alarm input demand is the grounding voltage signal.
- When the alarm is connected with two DVRs or connected with DVR and
other equipments, it should be isolated by relay.
2.7.2 Alarm output
Alarm output can not be connected with high-power load(no more than 1A).
When forming the output loop it must prevent the big current from relay
damage. Use the contact isolator when there is a high-power load.
2.7.3 PTZ decoder connections
A.The grounding of the PTZ decoder and DVR must be shared otherwise
the common-mode voltage will lead to the PTZ control failure. The shielded
twisted pair is recommended.
B. Avoid the entrance of high voltage. Make the layout reasonably. Take
precaution from the thunder.
C. In the outlying end connect 120Ω resistance paralleled to reduce the
inflection and insure the signal quality.
D. The 485 AB lines of DVR can not connected with other 485 output
equipments paralleled.
E.The voltage between the AB lines of the decoder must be less than 5V.
2.7.4 Front equipment grounding note
Bad grounding can lead to the burnout of the chip.
2.7.5 Alarm input type unlimited
The DVR alarm output port is constant opening type.
