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3.7
Connecting Audio Input & Output, Bidirectional Audio, Looping
Video, Matrix
For the 25-pin or 37-pin interface, different models include different functions.
See Figure 3-3.
Figure 3-3
3.7.1 Audio Input/One Audio Output
DVR-870PM has 8 looping video inputs, 1 matrix video outputs, 4 audio inputs, I
bidirectional audio input, 1 audio output.
The DVR encodes audio and video signals simultaneously, which lets you control
audio at the monitored location.
To set up audio:
1. Make sure your audio input device matches the RCA input level. If the device and
RCA input levels do not match, audio distortion problems may occur.
2. Make sure the audio connector is wired as follows:
3. Connect a line input device or pre-amplified microphone to the audio connector for
the video channel on the rear panel.
Please refer to Figure 3-4.
Figure 3-4
3.7.2 Looping
video
The DVR supports looping video. It passes the video input to a monitor or other
analog video device.
